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Equipment Discussions >> Cats & Casses

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Jeff Smith
professor emeritus


Reged: 04/06/10

Loc: Chicago
Edge HD Focal Reducer
      #3930821 - 07/19/10 08:36 AM

Any tried any focal reducers with their Celestron Edge HD's? I know Celestron is planning on coming out with a dedicated FR but has anybody tried using one of theirs? Would a screw-in FR work?
I find it hard to believe that they came out with a scope that is "almost" perfect for imaging but is restricted to f/10mm-f/11mm.


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Fred1
Carpal Tunnel
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Reged: 09/19/07

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Re: Edge HD Focal Reducer new [Re: Jeff Smith]
      #3930836 - 07/19/10 08:52 AM

Actually, it's Fastar compatible, so it's not restricted to f10 as the Fastar configures for f2.

I used the Siebert Optics Galaxy Viewer, a 6.3 focal reducer for binoviewers, in my Tele Vue Bino Vue. Also, I use the focal reducer setting in my Siebert 5 position Power Mag Wheel, as well as the focal reducer setting in my EarthWin system with no problem, but then I'm strictly visual. I used the EarthWin reducer setting with single eyepeices, also. I have not tried a conventional screw-into-the-visual-back FR.


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Jeff Smith
professor emeritus


Reged: 04/06/10

Loc: Chicago
Re: Edge HD Focal Reducer new [Re: Fred1]
      #3930859 - 07/19/10 09:19 AM

I have a 9.25" Edge HD and a Canon 450D. Celestron does not suggest using a DSLR for their Fastar scopes under 11" so I am probably out of luck there.
It's good to hear that you are able to use regular FR's for visual use with your Edge HD. There is hope.

Edited by Jeff Smith (07/19/10 09:20 AM)


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Starhawk
Space Ranger
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Reged: 09/16/08

Loc: Tucson, Arizona
Re: Edge HD Focal Reducer new [Re: Jeff Smith]
      #3930926 - 07/19/10 10:08 AM

Talk to Starizona. Celestron doesn't make any optics to go on a fastar interface anymore.

-Rich


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Jeff Smith
professor emeritus


Reged: 04/06/10

Loc: Chicago
Re: Edge HD Focal Reducer new [Re: Starhawk]
      #3930943 - 07/19/10 10:15 AM

Rich, I'm not looking for a Fastar setup. I was looking at an Optec reducer. It does not have a flattener built in so I was wondering if it would work with a 9.25" Edge HD. http://www.optcorp.com/product.aspx?pid=105-172-173-10164

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Thomas A Davis
Pooh-Bah


Reged: 03/25/05

Re: Edge HD Focal Reducer new [Re: Jeff Smith]
      #3931150 - 07/19/10 12:12 PM

I think the real issue is spacing. I tried the AP .75X
reducer (which does not have a built-in flattener), and
found that it had serious edge correction issues with my
9.25" EdgeHD. I used it as AP intended it, with their
SCT adapter. Celetron recommends 5.25" spacing between
the Schott flattener and the chip of a CCD or DSLR. How
that would translate to the use of a reducer with it, I'm
not sure. What I do know, and have posted proof of in
another thread, is that varying the spacing creates real
edge correction problems (it also changes the spherical
correction visually, much more that the same spacing change
would on a non-EdgeHD Celestron).

I've got a feeling that trying to use a focal reducer in
conjunction with a field flattener is creating fits for the
optical designers at Celestron, which is why we have not
seen one yet. At this point, anyone wanting to do SCT
imaging at anything other than F/2 (with HyperStar) or
native F/10 with the EdgeHD, would be better served using
a standard SCT with a reducer/corrector. It appears to be
more than just an issue of having a reducer that does no
field-flattening. In theory, a properly spaced reducer with
no field-flattening properties should work with the EdgeHD
flattener, but if that was all there was to it, I would
expect Celestron would have one available already. It may
be that a specially designed reducer may be needed (which
may even mean a specially designed unit for each size
EdgeHD SCT).

Tom


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Jeff Smith
professor emeritus


Reged: 04/06/10

Loc: Chicago
Re: Edge HD Focal Reducer new [Re: Thomas A Davis]
      #3931162 - 07/19/10 12:18 PM

Good points. I would have thought that a focal reducer with no correction of any kind would work if the astronomer was able to get the camera the proper distance from the back of the scope. I have read that Celestron will have different sizes of FR's when they come out.
I wish I could use my DSLR with the Hyperstar/9.25" HD but I have a feeling that I wont be able to.

Edited by Jeff Smith (07/19/10 12:19 PM)


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Thomas A Davis
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Reged: 03/25/05

Re: Edge HD Focal Reducer new [Re: Jeff Smith]
      #3931588 - 07/19/10 03:44 PM

I wouldn't worry about using a DSLR with the 9.25". It
won't be too heavy for it, and the obstruction of the
camera will not pose an issue. I got this from Dean at
Starizona. It will work with Hyperstar and the DSLR when
it comes out for the 9.25" (none available now) later in
the year.

Tom


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Jeff Smith
professor emeritus


Reged: 04/06/10

Loc: Chicago
Re: Edge HD Focal Reducer new [Re: Thomas A Davis]
      #3931613 - 07/19/10 03:58 PM

That's good news. I wan't worried about weight really. I was under the impression that Celestron and Starizona did not suggest using a DSLR with Fastar/Hyperstar on a scope under 11".

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mclewis1
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Reged: 02/25/06

Loc: New Brunswick, Canada
Re: Edge HD Focal Reducer new [Re: Jeff Smith]
      #3931861 - 07/19/10 06:27 PM

That's because currently the only product under the C11 Hyperstar is the C8 Hyperstar, and DSLRs (even the small ones) are quite large compared to the C8 secondary.

Celestron has virtually nothing to do with the Hyperstar product, this is all Starizona's game. Celestron talks up the concept of fastar and makes scopes with fastar compatible secondonaries, that's about the extent of it.


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Jeff Smith
professor emeritus


Reged: 04/06/10

Loc: Chicago
Re: Edge HD Focal Reducer new [Re: mclewis1]
      #3933796 - 07/20/10 05:00 PM

Makes sense. We'll see what Starizona comes up with for the 9.25". I'm not sure I want to spend that kind of money though. I would rather use a focal reducer in the back of the scope. It's tough imaging at f/10mm for me. I was hoping someone had tried out one of thier existing FR's and found it to work with the Edge HD.

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Jeff Smith
professor emeritus


Reged: 04/06/10

Loc: Chicago
Re: Edge HD Focal Reducer new [Re: Jeff Smith]
      #3935423 - 07/21/10 12:47 PM

I am going to call Optic about this: http://www.optecinc.com/astronomy/nguw_070.htm

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ewave
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Reged: 05/16/09

Loc: northwest NJ
Re: Edge HD Focal Reducer new [Re: Jeff Smith]
      #3936023 - 07/21/10 06:16 PM

Optec mostly for CCD chips no bigger than 18mm, too small for SLRs

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Jeff Smith
professor emeritus


Reged: 04/06/10

Loc: Chicago
Re: Edge HD Focal Reducer new [Re: ewave]
      #3936128 - 07/21/10 07:38 PM

Actually, I talked to Jeff Dickerman at Optec and had a great conversation with him about this. They now make a FR specifically for the Celestron Edge HD and Meade ACF series.
They are f/6.2mm focal reducers in the Lepus Series:

"Lepus 0.62X Telecompressor Lens

New 4-element telecompressor for use with new well-corrected SCT designs including the Meade ACF and Celestron EdgeHD optical tube assemblies. With a longer back-focus over 100mm, the Lepus 0.62X is capable of fully illuminating a 22mm diagonal CCD. Can be used with any filter wheel/camera combinations with room to spare and can also be used with DSLR cameras. Optimal back focus distance is maintained by new Lepus line of camera mounts. Contact Optec for camera-specific mount."

They sell for $199.00 and need a specific camera mount that sells for $95.00. Part #19407. They are listed on Optec's price list but no information yet on the website.

Here are two pictures that he sent me.

The back end of an 11" Edge HD with the FR and camera mount:


A shot taken with that setup without flat fields:


Jeff is going to send me a processed image when the processing is complete.

This looks promising.


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ewave
Pooh-Bah
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Reged: 05/16/09

Loc: northwest NJ
Re: Edge HD Focal Reducer new [Re: Jeff Smith]
      #3936167 - 07/21/10 08:04 PM

Hope so....it looks close to the recommended 5.25 inches from schott lens to camera sensor. Still for CPSC sized sensors, it is about a 27mm light cone.

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Jeff Smith
professor emeritus


Reged: 04/06/10

Loc: Chicago
Re: Edge HD Focal Reducer new [Re: ewave]
      #3936262 - 07/21/10 09:03 PM

Jeff told me that it would be at 22mm for my DSLR but he also said that flats would be necessary based on the pics he has seen.

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Chris Rowland
professor emeritus


Reged: 02/28/05

Re: Edge HD Focal Reducer new [Re: Jeff Smith]
      #3937794 - 07/22/10 04:26 PM

What puzzles me about the Optec FR is how it can be OK for both the ACF and ED scopes.

AIUI the ACF is coma free but has a curved focal plane while the ED is both coma free and has a flat focal plane.

How can one FR correct for the curved focal plane in one case and the flat focal plane in the other?

Chris


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bradisback
member


Reged: 01/05/10

Re: Edge HD Focal Reducer new [Re: Chris Rowland]
      #3938815 - 07/23/10 05:10 AM

+1 Chris

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Jeff Smith
professor emeritus


Reged: 04/06/10

Loc: Chicago
Re: Edge HD Focal Reducer new [Re: bradisback]
      #3938923 - 07/23/10 08:11 AM

Good point. I may call Jeff back later today and get a clarification.

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bradisback
member


Reged: 01/05/10

Re: Edge HD Focal Reducer new [Re: Jeff Smith]
      #3939005 - 07/23/10 09:13 AM

It would be nice!!

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freemanpa
journeyman


Reged: 06/16/10

Re: Edge HD Focal Reducer new [Re: Jeff Smith]
      #3939289 - 07/23/10 11:22 AM

The pictures posted in message #3936128 are of my equipment (EdgeHD 11" and Canon 50D DSLR) and it's also my shot of NGC6992. I've had limited time out in non-foggy Ohio skies but I was happy with that shot. It was taken the same evening as when the picture of the setup was also taken.

The only reason the flat was not applied was simply that I forgot it until after I had switched to f/10 for a comparison shot. Jeff did ask me to apply a flat that I got through nearly-identical setup the following weekend, which I did, and it did a nice job of eliminating the lighter center. I am at work now or I would post that shot, if I can remember after getting home I will do so. Jeff does have that shot now also.

Overall, I have been quite happy with the image quality using Optec's FR. Next up is to try the same thing all over again using their TCF-Si focuser, which is being delivered today!

Here's hoping the Ohio skies cooperate over the next few weeks...

-- Pat Freeman


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Bowmoreman
Clear enough skies
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Reged: 09/11/06

Loc: Bolton, MA
Re: Edge HD Focal Reducer new [Re: freemanpa]
      #3939345 - 07/23/10 11:57 AM

Hey Pat, welcome to CN and thanks for sharing your information with us.

Looking forward to having you as another active participant!

clear enough skies


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Jeff Smith
professor emeritus


Reged: 04/06/10

Loc: Chicago
Re: Edge HD Focal Reducer new [Re: Bowmoreman]
      #3939755 - 07/23/10 03:17 PM

Thanks for chiming in Pat. When I chatted with Jeff at Optec, I was unclear if the focal reducer you used in those pictures was a production model or if you were testing it out for Optec. Either way, Jeff seems excited about your particular setup and it's results so far. I hope you don't mind me posting those pictures of your setup and your shot of NGC6992. They inspiring for those of us that hate imaging in f/10 and waiting for a focal reducer solution for the Edge HD's.

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Jeff Smith
professor emeritus


Reged: 04/06/10

Loc: Chicago
Re: Edge HD Focal Reducer new [Re: Jeff Smith]
      #3939762 - 07/23/10 03:19 PM

It looks like OPT is selling the Lepus FR now and they also claim that it works with the Edge HD series and the Meade ACF series. http://www.optcorp.com/product.aspx?pid=105-172-173-15316

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Nocturnal
Carpal Tunnel
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Reged: 09/14/05

Loc: CT, USA
Re: Edge HD Focal Reducer new [Re: bradisback]
      #3939841 - 07/23/10 03:56 PM

Optec is here at MWAIC in Chicago so I'll ask them about this and report back.

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freemanpa
journeyman


Reged: 06/16/10

Re: Edge HD Focal Reducer new [Re: Jeff Smith]
      #3941847 - 07/24/10 04:47 PM Attachment (277 downloads)

Hi Jeff, no worries at all for posting those shots...I sent them to Jeff at Optec for his use anyway. I must say I was a bit surprised to see them here on CN, though.

Anyway, as promised, here is the same shot of NGC6992 with a flat-field applied from the week after the original shot.


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nemo129
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Reged: 01/03/10

Loc: WMass
Re: Edge HD Focal Reducer new [Re: freemanpa]
      #3941892 - 07/24/10 05:12 PM

Pat,
That is a beautiful shot of the Veil. Looks like Optec/Lepus beat Celestron to the punch here. Thanks to you and Jeff I have just figured out where my next $260 is going!! Astrophotography...the hobby that just keeps on taking!!

Thanks for sharing and welcome to Cloudy Nights!


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nemo129
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Reged: 01/03/10

Loc: WMass
Re: Edge HD Focal Reducer new [Re: nemo129]
      #3941920 - 07/24/10 05:26 PM

One thing I just noticed on the OPT website was the only DSLR adapter they sell for the Optec Lepus 0.62x Reducer is for Canon cameras right now. I hope they do not leave out the other brands of DSLR on the market. I realize this is a new product, so maybe those adapters will be coming. SOmething to keep in mind if you have a Nikon, Sony or other brand DSLR.

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ewave
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Reged: 05/16/09

Loc: northwest NJ
Re: Edge HD Focal Reducer new [Re: nemo129]
      #3941987 - 07/24/10 06:05 PM

Kirk

I am not sure the camera adapter is specific for each camera...my thoughts on this would hold true specifically for the T-Ring, not the adapter....Hmmmm??? I will have to call OPT on this one.


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Jeff Smith
professor emeritus


Reged: 04/06/10

Loc: Chicago
Re: Edge HD Focal Reducer new [Re: ewave]
      #3942051 - 07/24/10 06:44 PM

There is an adapter for each camera made by Optec. They are $60.00 each if memory serves me. The combination of the focal reducer, adapter and spacing will provide the needed reduction according to Jeff at Optec.

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nemo129
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Reged: 01/03/10

Loc: WMass
Re: Edge HD Focal Reducer new [Re: ewave]
      #3942161 - 07/24/10 07:58 PM

Sean,
Good idea to call. I just trolled through the 3 pages of camera adapters they link to on the FR page. link Lots of SBIG adapters and other CCD's but none specific to any other brand of DSLR except the Canon. Maybe the Canon one is just general enough for any DSLR...I am not sure if the adapter has a t-ring on it. Maybe Pat can chime in since he has one and there are no pictures on the OPT site yet. I have a Canon, so I am not worried. I just remebered that you have a Nikon and Donnie has a Sony.


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Jerry Hyman
sage


Reged: 03/29/07

Loc: Mesa, Arizona
Re: Edge HD Focal Reducer new [Re: nemo129]
      #3942218 - 07/24/10 08:37 PM

What do you folks think about this FR for visual? Would most eyepieces come to focus?

~jerry


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freemanpa
journeyman


Reged: 06/16/10

Re: Edge HD Focal Reducer new [Re: nemo129]
      #3942225 - 07/24/10 08:39 PM

Actually, I have two adapters. One is specifically for the Canon. The other is specific to my SBIG ST8300M CCD camera with filter wheel, but it just has a T-thread on one end because that's how the ST8300M is attached. These adapters have barrels with specific lengths that are joined to the camera adapters (Canon bayonet or T-thread). I just checked and even the Canon adapter is simply a barrel of specific length with a T-thread on it, onto which a standard Canon bayonet T-adapter is attached. I would suggest working with Jeff at Optec to get a Nikon adapter. It's probably about as simple as determining the needed length of the barrel, since Nikon probably needs to be a few mm different in length since the Nikon and Canon focal planes are probably slightly different, which I seem to remember is the case. Or, if they are close enough, just buy the Canon and replace the T-adapter on it with the Nikon version.

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nemo129
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Reged: 01/03/10

Loc: WMass
Re: Edge HD Focal Reducer new [Re: freemanpa]
      #3942365 - 07/24/10 10:29 PM

Pat,
Thanks for the info. I am sure it will help out the interested parties here. The suggestion to speak directly to Optec regarding specific configurations is good advice.


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ewave
Pooh-Bah
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Reged: 05/16/09

Loc: northwest NJ
Re: Edge HD Focal Reducer new [Re: nemo129]
      #3942885 - 07/25/10 08:22 AM

Thanks guys.....I will call them Monday...just seems to me there is a standard male thread that screws into the female t-ring of each camera, that's all....spacing should not be an issue, unless we are talking about the spacing of the FR to the sensor ....I was also told by Celestron that the 5.25" recommended flange to sensor distance does have some wiggle room to about a quarter of an inch for fine results.

Can anyone post a picture of this Canon adapter?

Edited by ewave (07/25/10 08:43 AM)


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Jeff Smith
professor emeritus


Reged: 04/06/10

Loc: Chicago
Re: Edge HD Focal Reducer new [Re: ewave]
      #3942935 - 07/25/10 09:03 AM

Quote:



Can anyone post a picture of this Canon adapter?




Look on page one of this thread.


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freemanpa
journeyman


Reged: 06/16/10

Re: Edge HD Focal Reducer new [Re: ewave]
      #3942940 - 07/25/10 09:08 AM

Hi Sean, the first picture in message #3936128 shows this adapter, installed on my EdgeHD 11". More specifically, it's inserted into an Astro-Physics rear-cell adapter...if using a electric focuser, that Optec adapter would insert into the focuser instead. The Optec adapter does indeed establish the distance from the FR to the sensor. The FR is inserted into the end of the Optec adapter closest to the telescope...you can see one of the set screws that holds it into the Optec adapter in message #3936128, on the end closest to the Astro-Physics piece. The camera end is simply a T-thread with a standard Canon T-adapter attached. You can see the edge of that T-adapter at the camera end in the picture.

-- Pat Freeman


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PatHolland
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Reged: 10/11/09

Loc: Clever, Missouri
Re: Edge HD Focal Reducer new [Re: freemanpa]
      #3962938 - 08/04/10 02:59 AM

I've just ordered one for my ACF scope. Although the Meade .63 focal reducer does work fine with the ACF, there is a bit of "stretched star" activity on the edges of my images when the Meade reducer is used. I'll test it as soon as it is received and I'll post images and a quick review.

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Jeff Smith
professor emeritus


Reged: 04/06/10

Loc: Chicago
Re: Edge HD Focal Reducer new [Re: PatHolland]
      #3967935 - 08/06/10 04:00 PM

I just got mine in the mail from Optec .

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elwaine
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Reged: 06/18/06

Loc: Jupiter
Re: Edge HD Focal Reducer new [Re: Jeff Smith]
      #3970170 - 08/07/10 10:54 PM

Pat,

Quite a nice image of the Veil. But I have a question regarding the use of flat field correction in the Edge HD series.

Without dividing the image by the flat, there is quite a striking central light zone, as you yourself mentioned. Celestron advertises the Edge series as having an "...optical system [which] was designed to reduce more than just off-axis star coma, but also to give an astrograph quality flat focal plane all the way to the edge of the field of view."

In fact, there is an image of a galaxy at the bottom of the page on this Celestron site that shows a uniform exposure across the entire frame and no central light zone. It does not appear to have been flat field corrected (see the two dust donuts to the left of the galaxy core when you zoom in to enlarge the image).

So, if the field is flat, I'm thinking that the striking central light zone in your first image is caused by the FR. Is that correct? If it is, do all FRs cause such non-uniform fields of illumination?


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elwaine
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Reged: 06/18/06

Loc: Jupiter
Re: Edge HD Focal Reducer new [Re: elwaine]
      #3974758 - 08/10/10 12:58 PM

Bump

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Jeff Smith
professor emeritus


Reged: 04/06/10

Loc: Chicago
Re: Edge HD Focal Reducer new [Re: elwaine]
      #3974917 - 08/10/10 02:19 PM

Well, when I get a clear night, I'll test out my new Optec focal reducer system for you .

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Konihlav
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Reged: 03/05/09

Re: Edge HD Focal Reducer new [Re: Jeff Smith]
      #3974997 - 08/10/10 03:10 PM

that would be great Jeff I am interested too.

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elwaine
Pooh-Bah


Reged: 06/18/06

Loc: Jupiter
Re: Edge HD Focal Reducer new [Re: Jeff Smith]
      #3975029 - 08/10/10 03:27 PM

Thank you Jeff.

I hope to be able to use a Featertouch "shorty" Crayford, plus an AO-8 with my ST-8XME. I do not plan to use a color filter wheel. Total backfocus is approximately 5.75 to 6 inches. That will work fine for my Edge 9.25 without the Optec FR. But it seems to me that the backfocus with their filter in place is much more critical than the backfocus tequiremts for the scope at it's native f/10. I am also concerned about the central "hot spot."

Regards


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Peter in Reno
Postmaster
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Reged: 07/15/08

Loc: Reno, NV
Re: Edge HD Focal Reducer new [Re: elwaine]
      #3975049 - 08/10/10 03:35 PM

It would be best to test with a camera. Did Optec listed a required spacing distance specifically for EdgeHD? Since the EdgeHD has a flattener inside baffle tube, there may be a required distance between flattener and focal reducer AS WELL AS distance between focal reducer and camera.

I have a hard time seeing any focal reducer would work with EdgeHD with a flattener already installed inside the baffle tube. This is why I have not bought EdgeHD yet. Who would image all DSOs at F/10? And why is it taking Celestron so long to create a perfect focal reducer for all sizes EdgeHD?

Peter


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Konihlav
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Reged: 03/05/09

Re: Edge HD Focal Reducer new [Re: Peter in Reno]
      #3975113 - 08/10/10 04:10 PM

Peter in Reno: I have the same doubts and concerns about the spacing.

Anyway I decided to do DSO imaging at F/10 with large format CCD and binning 2x2 and/or 3x3 in the worst cases of bad seeing and objects low above horizon (we'll see later if it's feasible to do it this way or not) so I get the EdgeHD soon.


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elwaine
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Reged: 06/18/06

Loc: Jupiter
Re: Edge HD Focal Reducer new [Re: Konihlav]
      #3975483 - 08/10/10 07:23 PM

The distance from the back of the OTA to the plane of the camera sensor can be adjusted by getting longer or shorter spacing tubes, onto which one attaches his/her camera specific T-adapter. I don't see that as a problem. I'm more concerned about the apparent non-uniform image brightness. That sort of defeats the flat field design of the Edge, doesn't it?

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freestar8n
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Re: Edge HD Focal Reducer new [Re: elwaine]
      #3975513 - 08/10/10 07:37 PM

Hi-

Unfortunately there is a lot of confusion about what exactly "flat field" means. In an optical context - it means that the surface of best focus across the image lies in a plane. Note that does NOT mean the stars are small all the way across - it just means that the stars are at their best in a plane, and moving up or down in focus will make all stars worse everywhere.

You could have a flat field that had bad coma and astigmatism - and the stars looked terrible as you went out from center - but it would still be a flat field. You could also have what looks like a flat field with round stars across it - but in fact the field is curved and when you change focus, they get smaller in one area and bigger in another.

In the case of Edge HD, flat field means small, round stars across a large, flat ccd - as shown in images.

Now you are commenting on an issue of vignetting - which is yet something else. You could have a flat field with strong vignetting and it would still be a flat field.

In the case of Edge HD - it is designed to have a flat field with low vignetting at f/10. There is no reducer for it just yet - but if there is low vignetting at f/10, then I think you can expect some vignetting with a reducer. Since the field is already flat and well corrected, I don't think a reducer will enlarge the usable field much, but it will make the same angular field smaller and brighter through the faster f/ratio.

No matter what - some vignetting, and even pretty strong vignetting - will disappear with a good flat applied. But if the star shapes are bad - then there is no fix for that. So - vignetting is tolerable, but messed up stars are not.

Frank


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Jeff Smith
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Re: Edge HD Focal Reducer new [Re: Peter in Reno]
      #3975591 - 08/10/10 08:24 PM

Quote:

It would be best to test with a camera. Did Optec listed a required spacing distance specifically for EdgeHD? Since the EdgeHD has a flattener inside baffle tube, there may be a required distance between flattener and focal reducer AS WELL AS distance between focal reducer and camera.

I have a hard time seeing any focal reducer would work with EdgeHD with a flattener already installed inside the baffle tube. This is why I have not bought EdgeHD yet. Who would image all DSOs at F/10? And why is it taking Celestron so long to create a perfect focal reducer for all sizes EdgeHD?

Peter



As far as the spacing for the Edge HD and the Optec focval reducer, Jeff assured me that their combination of Canon tube and the Lepus f.r. is the correct spacing. He also suggested the Astro Physics 3.25" visual back to keep the whole thing tight. I have one on back order butin the mean time I have an old Celestron back that I am going to try out tonight. The skies are *BLEEP* tonight as are my skills but I can at least take an hour and a half of M51 and compare the results to my earlier attempts at f/10. I also have a new Astronomik CLS-CCD filter that I am going to try out tonight so my results will be a bit skewed.
The Optec unit is just a focal reducer. There is no field flattener built in to it. It is made for the Meade ACF and the Celestron Edge HD. I do believe that Celestron's focal reducer will be great when it comes out.


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elwaine
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Re: Edge HD Focal Reducer new [Re: Jeff Smith]
      #3975786 - 08/10/10 09:58 PM

Hey Frank, that was very helpful Thank you!!!

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Jeff Smith
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Re: Edge HD Focal Reducer new [Re: elwaine]
      #3975867 - 08/10/10 10:41 PM

Too cloudy tonight. I'm not going to be able to test out the focal reducer yet.

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saadabbasi
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Re: Edge HD Focal Reducer new [Re: Jeff Smith]
      #3976410 - 08/11/10 09:33 AM

I'm wondering about getting myself a C9.25 HD too, for some long focal length imaging. But yes, the F10 is very daunting and I would really like a reducer in the 0.63x range that brings the FL down to ~1500mm. I intend to use the reducer with my SBIG ST8300M and maybe with a 35mm DSLR. Will the Optec do the job? Or is it designed only for Canon DSLRs?

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Re: Edge HD Focal Reducer new [Re: saadabbasi]
      #3976459 - 08/11/10 10:03 AM

Saad, I think it should work with any camera. I would think the only variable might be distance from the CMOS or CCD chip. It is possible that larger imaging chips may reveal more vignetting though.

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saadabbasi
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Re: Edge HD Focal Reducer new [Re: PatHolland]
      #3976723 - 08/11/10 12:07 PM

Thanks for the response Pat. I ask about the 35mm format because I may buy a D700 used. The 35mm will provide rather wide views. However, am I correct in assuming that flat frames will removing vignetting completely? Or will the vignetting be so severe that flats cannot fix it?

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Micheal
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Re: Edge HD Focal Reducer new [Re: saadabbasi]
      #3981291 - 08/13/10 04:51 PM

I just got mine today but the camera adapter seems to be lost out there in internet land. Been trying to get optcorp to locatate it but I seem to be running into trouble there. So I am staring at this thing and trying to imagine how to set it up. Says right on the box Lens Assembly Mounted for use with 2" motorized focuser which I do not have and have no interest in. Looks like one end of this would fit into the visual back or focuser of the telescope but it is very short. The other end has a weird slanted beveled edge to it which I assume is so that it only works with other optec accessories. I'll post some photos shortly.

Edit: Just got off the phone with Optcorp.com and they said it is about 1.5 weeks away still for the camera adapter.

Posted the below thumbnails. Click them to blow them up.











Edited by Micheal (08/13/10 05:33 PM)


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GlennLeDrew
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Re: Edge HD Focal Reducer new [Re: Micheal]
      #3981892 - 08/13/10 11:34 PM

Michael,
Nice photos. Seeing as you're stuck with just staring at it for some time, how's about taking a measurement of the clear aperture? This would at least begin to give some idea of possible illumination characteristics at the focal surface once the lens-to-focus distance is known.

Thanks!


Larry (elwaine),
Frank (freestar8n) provided a most lucid explanation of the meanings of flat field and 'flat' illumination. (Thanks, Frank!) Until I'd read his post, I had copied a snippet of your text just prior, to which I'd planned to reply in like kind.


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PatHolland
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Re: Edge HD Focal Reducer new [Re: saadabbasi]
      #3982067 - 08/14/10 02:01 AM

Quote:

Thanks for the response Pat. I ask about the 35mm format because I may buy a D700 used. The 35mm will provide rather wide views. However, am I correct in assuming that flat frames will removing vignetting completely? Or will the vignetting be so severe that flats cannot fix it?




I don't know the answer but I am expecting my reducer to arrive any time now. Opt e-mailed me and told me it's on the way (no shipping info on the e-mail though). When I get mine in I'll test it with my XSi (26mm) andI'll post the results.


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elwaine
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Re: Edge HD Focal Reducer new [Re: PatHolland]
      #3982268 - 08/14/10 08:00 AM

Flat frames should remove vignetting across the entire field. However, obtaing good flats is not as easy as getting a good master dark frame. There is a definite skill involved getting quality flats, but once one gets the knack, they will remove vignetting across the entire field and several other flaws as well.


Glenn,

I agree. Until I read his explanation I was confused about exactly what a flat field is.


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freemanpa
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Re: Edge HD Focal Reducer new [Re: elwaine]
      #3985904 - 08/16/10 09:44 AM

Hi, sorry for the delay...I've been so busy with work and play that I haven't been out to CN for at least a week or two.

Anyway, the flat field will definitely resolve the vignetting. I have not yet tried to shoot at f/10 so I can't say with my EdgeHD 11" if it shows much vignetting. But my experience is that the FR on just about any OTA I've used will increase vignetting...leading to the certain need for flats.

A later post comments on the initial trickiness around getting good flats...I agree, but I was so determined to get flats (I know some folks who simply refuse to take 'em) that I learned quickly. On the DSLR, it's really not hard at all...just snap a flat and check for the histogram being near the center or at least away from either end. As I'm now also learning CCD photography, it's a bit more complex but I'm learning that too. And the biggest help for me was making my own flat-field boxes...one for the larger OTAs I own and one for the smaller refractors. I made it with foam-core board (white on inside, black on outside), lots of black duct tape (that stuff is great for so many "guy things"!) and four incandescent bulbs from Radio Shack. Oh, and a fair amount of hot-melt glue and a few other odds and ends from Home Depot. Cost me under $75, and most of that was the foam-core. Watch for sales on that. :-)


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Jeff Smith
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Re: Edge HD Focal Reducer new [Re: freemanpa]
      #3999680 - 08/22/10 05:11 PM

Well, good news and bad news.
Good news:I got mine and it works great. It really helped my efforts.
Bad news: I need to sell it. I'm selling some equipment because of a family emergency. If anybody is looking for a good deal on the focal reducer and Canon adapter let me know.

Edited by Jeff Smith (08/22/10 05:11 PM)


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Konihlav
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Re: Edge HD Focal Reducer new [Re: Jeff Smith]
      #4001298 - 08/23/10 01:14 PM

Jeff Smith:

could you please tell piece by piece how you mount the Optec Lepus reducer to the back end of the EdgeHD OTA? I mean start with Astro-Physics 3.25" adapter... ... how far is the Lepus from the back end? and the spacing from the reducer to focal plane is 100mm ??? isn't that too large?

many thanks and I feel sorry for the bad news above...


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Jeff Smith
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Re: Edge HD Focal Reducer new [Re: Konihlav]
      #4004079 - 08/24/10 09:02 PM

Yes, I had an Astrophysics visual back. It fits the large rear cell and has a triple thumbscrew 2" opening. Into that goes the focal reducer with the Canon adaptor attached. On the back of the Canon Adaptor is a Canon T ring that attaches to the Canon camera.
Scope->A.P. visual back->Optec focal reducer->Canon adaptor->T Ring->camera.
If you get the Optec setup you get the focal reducer, Canon Adaptor and T ring. It is all setup for optimum spacing.
The focal reducer will not work with a normal SCT visual back. It must go into a 2" thumbscrew focuser or visual back. Optec advised me to get the A.P. visual back and it was really nice.

Edited by Jeff Smith (08/24/10 09:03 PM)


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Konihlav
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Re: Edge HD Focal Reducer new [Re: Jeff Smith]
      #4007835 - 08/26/10 03:55 PM

thank you Jeff. So I make it AP 3.25" adapter (I've got the one with 2.7" threads) then I can put the Optec FR and then I somehow make it to be 100mm from the focal plane.
thanks.


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Dave M
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Re: Edge HD Focal Reducer new [Re: Konihlav]
      #4196678 - 11/19/10 12:03 PM

I`m aware of the Optec Lepus reducer for the Edge HD scopes, But! whats the story/word on when Celestron will make their
reducer available ?


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ewave
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Re: Edge HD Focal Reducer new [Re: Dave M]
      #4197342 - 11/19/10 05:59 PM

They now say early 2011 about a month ago

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Dave M
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Re: Edge HD Focal Reducer new [Re: ewave]
      #4198275 - 11/20/10 08:29 AM

Thanks! Sean

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PatHolland
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Re: Edge HD Focal Reducer new [Re: Dave M]
      #4198580 - 11/20/10 11:35 AM

I've got the Optec Lepus for the 10" LX200 ACF. Seems to work pretty good but since my main imaging chips are 26mm and 28.4mm I get coma on the edges. The Lepus illuminates a 22mm chip at F6.2. A bit of cropping takes care of that.

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Chris Fogarty
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Re: Edge HD Focal Reducer new [Re: Jeff Smith]
      #4294912 - 01/05/11 09:30 PM

Did you ever get Clarification?

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sfastroman
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Re: Edge HD Focal Reducer new [Re: Dave M]
      #4330372 - 01/21/11 05:53 PM

I sent an email to Celestron tech support asking if there was an E.T.A on an Edge HD Focal reducer and also asked if they could tell me what the area of illumination would be. Here is the response that I got back on 01/19/2010:

-----------------------------------------------------
We don't have any tech specs on the reducer yet. Nor do we have a firm date on its release. Sorry.

Clear skies,
Celestron Technical Support
-----------------------------------------------------

It's not looking too good...

Glenn


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kohudson
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Re: Edge HD Focal Reducer new [Re: sfastroman]
      #4330497 - 01/21/11 06:55 PM

Well, either it's no priority at all or they are having "trouble" somewhere along the line...

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ewave
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Re: Edge HD Focal Reducer new [Re: kohudson]
      #4330506 - 01/21/11 07:01 PM

awwwww....fishsticks

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houser23
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Re: Edge HD Focal Reducer new [Re: ewave]
      #4330677 - 01/21/11 08:40 PM

Why don't they just come out and say it. We just can't make a focal reducer for this telescope, it's impossible.

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starbob1
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Re: Edge HD Focal Reducer new [Re: houser23]
      #4330826 - 01/21/11 09:51 PM

LAWSUIT COMING SOON.

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dkb
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Re: Edge HD Focal Reducer new [Re: starbob1]
      #4330873 - 01/21/11 10:23 PM

What would be the technical limitation for them not being able to manufacture one? Is there something I'm missing that makes this extremely difficult to produce?

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Dave M
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Re: Edge HD Focal Reducer new [Re: sfastroman]
      #4332531 - 01/22/11 04:54 PM

At least you got a reply from them ,i sent a e-mail asking the same thing a while back but never got a reply.
Ide like to buy the 9.25" HD OTA this summer if possible, but i`m not going to until their reducer is made available.


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Snickersnee
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Re: Edge HD Focal Reducer new [Re: elwaine]
      #4402934 - 02/22/11 12:26 AM

Yep - FRs do cause central brightening. They emphasize the existing vignetting in the OS they are reducing.

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Cliff Halliwell
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Re: Edge HD Focal Reducer new [Re: Snickersnee]
      #4404957 - 02/22/11 10:56 PM

A most interesting take on this comes from Celestron's video pitching the new CGEM DX mount. Towards the end they turn to extolling the Edge OTAs and their large, flat field. Except they illustrate it with a DSLR on a Hyperstar which, of course, has zip to do with the Edge optical design changes!
See: http://www.celestron.com/c3/product.php?CatID=16&ProdID=761 (click on the video tab).


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Patrick
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Re: Edge HD Focal Reducer new [Re: Cliff Halliwell]
      #4405054 - 02/22/11 11:57 PM

Quote:

A most interesting take on this comes from Celestron's video pitching the new CGEM DX mount. Towards the end they turn to extolling the Edge OTAs and their large, flat field. Except they illustrate it with a DSLR on a Hyperstar which, of course, has zip to do with the Edge optical design changes!




Yes, that is odd.

Patrick


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bradisback
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Re: Edge HD Focal Reducer new [Re: Patrick]
      #4405282 - 02/23/11 04:38 AM

One thing that also surprises me is that the "edgeHD Availability" has not changed since November 2010.
They never speak of a focal reducer ...
The communication on this subject is deplorable!
Stef


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Nocturnal
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Re: Edge HD Focal Reducer new [Re: bradisback]
      #4405538 - 02/23/11 09:01 AM

Hmm, I checked a few weeks ago and I saw several OTAs and packages in stock. I'd say supply has improved in general but perhaps not for the model you're looking for

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bradisback
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Re: Edge HD Focal Reducer new [Re: Nocturnal]
      #4406240 - 02/23/11 02:44 PM

Thank's Sander,
I meant that: in their letter "edgeHD Availability", they spoke each time the reducer for edgeHD ...
But since this post from 16/11 nothing...


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Nocturnal
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Re: Edge HD Focal Reducer new [Re: bradisback]
      #4406246 - 02/23/11 02:47 PM

Sorry, I didn't understand you specially meant the reducer. Indeed we may never see that unit.

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ewave
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Re: Edge HD Focal Reducer new [Re: Nocturnal]
      #4406805 - 02/23/11 07:05 PM



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Chris Fogarty
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Re: Edge HD Focal Reducer new [Re: Nocturnal]
      #4439572 - 03/10/11 10:48 AM

This is what I got back from Celestron

=======================================================
The dedicated Celestron reducer is not available yet. However, we have good news for you:
There is a reducer available for the EdgeHD. It is the Optec Lepus 0.62x Reducer:

Alan Dyer of “Backyard Astronomer’s Guide” has tested it with the EdgeHD and gave it two thumbs up.

Information from the manufacturer:

19407Lepus 0.62X Telecompressor Lens$199.00New 4-element telecompressor for use with new well-corrected SCT designs including the Meade ACF and Celestron EdgeHD optical tube assemblies. With a longer back-focus over 100mm, the Lepus 0.62X is capable of fully illuminating a 22mm diagonal CCD. Can be used with any filter wheel/camera combinations with room to spare and can also be used with DSLR cameras. Optimal back focus distance is maintained by new Lepus line

OPT has it for sale.http://www.optcorp.com/product.aspx?pid=15316&kw=optec%20reducer&st=2 Thank you

Celestron Technical Services

===========================================================


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Mike Wiles
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Re: Edge HD Focal Reducer new [Re: Chris Fogarty]
      #4439836 - 03/10/11 12:43 PM

Alan Dyer mentions the focal reducer in his piece on the Edge HD, but the article most certainly does not say that he tested the combination in any way, shape or form. There is a photo taken by a completely different person not named Alan Dyer in the same issue with a completely different OTA than the one tested. Celestron's response is misleading at best.

In the interest of full disclosure - I do intend to buy the Optec reducer myself and make use of it and I do think that people who are cranky because they bought a telescope without a focal reducer shouldn't be surprised that they own a telescope without a focal reducer.

Having said that - I find Celestron's response to be misleading and not entirely true based on the information that I have.


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ewave
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Re: Edge HD Focal Reducer new [Re: Mike Wiles]
      #4440684 - 03/10/11 06:25 PM

I will pay big C a visit at NEAF next month and see if they will have a different response than last year's NEAF. I hope that hyperstar isn't the only way to image DSO's with these OTAs. At least they are also very good OTAs visually.

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freestar8n
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Re: Edge HD Focal Reducer new [Re: ewave]
      #4441208 - 03/10/11 10:28 PM

Quote:

I hope that hyperstar isn't the only way to image DSO's with these OTAs. At least they are also very good OTAs visually.




The C9.25 Edge at f/10 has a 2350mm f.l. and a coma free, flat field over a large dslr sensor. A 12" f/8 RC has a longer f.l. at 2438mm and has reduced coma but a curved field. I don't understand why a flat field f/10 instrument would be considered only good for visual, while an f/8 instrument of longer focal length and a curved field is considered ideal for imaging - especially given some of the impressive example images taken with Edge HD at f/10 - with small stars and detailed galaxies across a wide field.

Frank


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ewave
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Re: Edge HD Focal Reducer new [Re: freestar8n]
      #4441775 - 03/11/11 07:44 AM

mostly because nobody wants to take the painly time to image at F10

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freestar8n
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Re: Edge HD Focal Reducer new [Re: ewave]
      #4441910 - 03/11/11 09:33 AM

Quote:

nobody wants to take the painly time to image at F10




That's a pretty sweeping statement. Actually - many people spend a ton of money for RC's around f/9. Even f/8 isn't a lot different in exposure time for the same ADU compared to f/10. The difference in exposure is probably greater due to the different cameras people use. For big RC's with smallish chips, the field curvature matters less and they get very high res. results that appear as APOD's. Check the RCOS gallery for example. People are imaging in the f/8-f/10 realm all the time, and as long as the focus and guiding are good - the benefit of the image scale shows. The eskimo nebula is often shot with a Barlow in the f/10-f/20 realm.

The difference with Edge is that the aperture tends to be smaller than large RC's and the angular field tends to be bigger, with dslr sized chips. This places greater requirements on having a flat field. So - you end up with a flat field version of a coveted high end RC with similar operating f/number but at much lower cost and easier to collimate due to spherical elements. Plus - you can switch to flat field at f/2 with hyperstar where you may not even need to autoguide.

Frank


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Samir Kharusi
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Re: Edge HD Focal Reducer new [Re: freestar8n]
      #4441958 - 03/11/11 10:12 AM

I suspect that most imagers using slow scopes (f8 to f11) use astroCCDs (mono) that are straightforward to bin. Huge impact! Since seeing is typically worse than 2 arc-sec FWHM, one can get away with binning a camera and end up sampling, at say, 0.7 to 1 arc-sec per pixel. The binned sensor will then be happy imaging with reasonable length subs. If one were using a DSLR, e.g. a Canon 550D, at a focal length of 3000mm, he would be sampling at 0.3 arc-sec / pixel, way overkill. To make things worse, he would need subs around 15 minutes each (at a dark site) at f11 to get into skyfog-statistics-limited regime, not many people's cuppa tea. Personally, I still find the Hyperstars really, really good and great value for money. Sharper than many premium APOs of similar focal length as indicated here. With the current tiny-pixel DSLRs one is getting pretty close to Nyquist sampling the seeing FWHM on average nights. With the same size pixels one would be over-sampling at f6.2. So one really ought to consider the pixel/focal-length matching before choosing, just like in the olden days. The formula for sampling:

arc-sec/pixel =206*W/f

W is pixel width in microns, f is focal length in mm. Of course if binned, W is the binned pixel width. Ideally I would like to image at about 1 arc-sec / pixel, overkill on average nights, but already there if you happen to have a night with excellent seeing. A Canon 550D delivers around 1.3 to 1.6 arc-sec/pixel with the Hyperstars, an excellent match for average nights, but not quite there on exceptionally steady nights.


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Nocturnal
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Re: Edge HD Focal Reducer new [Re: ewave]
      #4441987 - 03/11/11 10:25 AM

I don't really get that. There's nothing inherently 'bad' about F/10. Sure you get fewer photons per pixel but you get a more detailed picture (as far as conditions allow anyway).

So yes, I intend to buy an Edge HD11 -specifically- because it is flat at F/10. I want that long focal length so I can take more detailed images. Sure with the C11 at F/2 your get more ADUs in less time but the picture scale is different so it's a pointless comparison. Unfortunately Starizona does the same with their hyperstar ads. I got the HS3 for my C11 because I was using about the same FL with my WO M110. Same FL but much larger aperture -> same image scale but much reduced exposure times.


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nemo129
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Re: Edge HD Focal Reducer new [Re: Nocturnal]
      #4442042 - 03/11/11 10:55 AM

Don't forget that along with those longer subs, you increase the risk of guiding and tracking errors. Yes, I know they can be mitigated with good polar alignement via drift align, PEC and putting your mount on a solid pier or buying yourself a real nice Astrophysics mount, but not everyone has those options. I do agree that you can get some great details at f/10, but as Sean said above it can be a pain to deal with the length of the subs for various reasons. I would certainly be gratified if Celestron would produce the long promised FR for the HD series of SCTs, just so I can have more imaging options for my EdgeHD 1100. I still am not sold on the Optec Lepus offering because no one seems to be pumping out great shots with them (at least no more than one or two here or there...just look in the AP forums...I see none!) and I have seen no legitimate in depth reviews (aside from a one line mention by Alan Dyer of “Backyard Astronomer’s Guide” ...not even a review!) My point it the thread is about a FR for the EdgeHD's and not the merits of imaging at F/10 necessarily as the two subjects share common ideas, but are not the same issue. Don't get me wrong I agree with many of your points and I enjoy imaging some objects at F/10 and with my incoming G11, I think I will like it even more than I did on my CGEM.
Clear skies!


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DeanS
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Re: Edge HD Focal Reducer new [Re: nemo129]
      #4442054 - 03/11/11 11:00 AM

My concern is there are already too many optical surfaces in this design before you even add a focal reducer.

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nemo129
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Re: Edge HD Focal Reducer new [Re: DeanS]
      #4442062 - 03/11/11 11:04 AM

Good point Dean, I could not argue with that.

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Nocturnal
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Re: Edge HD Focal Reducer new [Re: nemo129]
      #4442076 - 03/11/11 11:08 AM

I agree that astro photography is about the total system, not just one component. There's no free lunch, long FLs put more demands on other parts of your system than short FLs.

It is for this reason I recently bought a Takahashi EM-400

As for the Lepus I'm not sure why you'd be reluctant to give it a try. It's not an expensive piece and it's made by a respected manufacturer. That's not to say we should always believe what we're told. I've had Televue recommend one of their flatteners for my refractor and it sure didn't work so great until I tuned it myself.

We can't always wait for someone else to clear a path. If you're eager to have an FR for your Edge, buy one already and decide how well it works. Write a review for one of the mags. Make a deal with your vendor that you'll return it if you can prove that it's no good. *Do Something*.

Or keep waiting for C to deliver an FR. And then wait some more for someone else to tell you if it's OK.


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Peter in Reno
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Re: Edge HD Focal Reducer new [Re: Nocturnal]
      #4442112 - 03/11/11 11:21 AM

Maybe if they made the built-in field flattener inside EdgeHD removable to replace it with a focal reducer. This way you won't need two flatteners in series.

I don't own an EdgeHD but does it look simple enought to remove the built-in flattener and try use regular Celestron F/6.3 focal reducer. Would that work?

Peter


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Nocturnal
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Re: Edge HD Focal Reducer new [Re: Peter in Reno]
      #4442134 - 03/11/11 11:28 AM

Yes, I proposed that type of setup a while back too. It seems such an obvious thing to do to make the FR replaceable that there much be a technical hurdle we're not aware of.

I don't know if the FR is removable while still remaining intact If it was then the stock F6.3 should work. I've never used it with my C11 so I don't know what kind of results to expect with an APS-C size camera. Since it's a rather old device I imagine it's not suitable for such large sensors.


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freestar8n
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Re: Edge HD Focal Reducer new [Re: Nocturnal]
      #4442161 - 03/11/11 11:43 AM

It's pretty clear now that the Edge design is not a normal sct plus flattening lenses, but a system designed as a whole. There are many reasons to do this and it's been discussed in other threads. So - you definitely can't remove the flattener and have a good image - and you similarly can't remove the flattener and use it with the normal 6.3 reducer. I assume there is intentional spherical aberration built in to the uncorrected system - but I don't know for sure.

You can't replace the flattener itself with a special reducer/flattener because it wouldn't have enough backfocus at f/6 or whatever to give a well illuminated field. A fast reducer would need to be relatively close to the image plane.

A key point is that the system has moving spherical surfaces for collimation, and the flattener lens system is factory installed and permanently aligned. This is an advantage over systems with parts that are generically screwed on without special alignment, or where moving components are aspherical. An add-on reducer wouldn't have this factory alignment, but hopefully the fact that the core f/10 system is well collimated would help make an add-on reducer work well.

I'm also interested in well-guided and focused results with the Lepus reducer. One advantage of reducing a flat-field system is that they don't need to be specifically matched to a particular radius of curvature. So they have a better chance to work well with different apertures - 8-14". There is little difference in coma, field curvature, or f/number across them.

Frank


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Alph
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Re: Edge HD Focal Reducer new [Re: Nocturnal]
      #4442492 - 03/11/11 02:40 PM

Quote:

I don't really get that. There's nothing inherently 'bad' about F/10.



high focal ratio = narrow field of view = planatery telescope
astrograph = low focal ratio = wide field of view


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Nocturnal
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Re: Edge HD Focal Reducer new [Re: Alph]
      #4442511 - 03/11/11 02:50 PM

Sorry, that's much too generic.

I assume you have Ron W's CCD Calculator installed. Pick a C11 @ F/10 and enter the values for a QHY8. Now look at M51. All of it easily fits in the FOV. And because the Edge is flat all of it will be good to use.

Planetary setup only? Don't think so. I've been shooting at short FLs for a while now and while it's certainly nice to have a 2.5 by 1.5 degree field I would really like to get a little closer. Call it a change of pace.


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freestar8n
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Re: Edge HD Focal Reducer new [Re: Alph]
      #4442620 - 03/11/11 03:53 PM

f/ratio and field of view are totally independent depending on how the aberrations have been corrected. You could have a fast scope with a narrow field of view and a slow scope with a wide field of view. A common f/ratio for a high end RC is f/9, so I guess you consider them only good for planets.

The real measure of an astrograph is that it is well corrected over the entire intended field - which is usually made wider through additional optics since the field doesn't just flatten by itself.

Frank


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Bill Shaheen
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Re: Edge HD Focal Reducer new [Re: Jerry Hyman]
      #4457739 - 03/18/11 12:04 PM

Hi, jerry -

For my HD9.25, I experimented with an Antares 0.5x reducer and found it to be acceptable for visual and even for astrophotography, to a degree. Here is a link to a comparison of images: http://www.pbase.com/wjshaheen/image/131099703

I have however since upped the ante to the 11 inch EdgeHD and the results are not nearly as satisfying for AP but seem acceptable for visual.

You are more than welcome to borrow the Antares as I would be interested in your evaluation. Let me know and we can hook up - meaning you can buy me a cofee at the Gecko.


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lightfever
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Re: Edge HD Focal Reducer new [Re: Bill Shaheen]
      #4458279 - 03/18/11 04:22 PM

Bill

Did you screw the reducer into the diagonal?


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starbob1
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Re: Edge HD Focal Reducer new [Re: lightfever]
      #4458511 - 03/18/11 06:48 PM

Hi Bill could you give more info on the Antares reducer.What type of camer was used and where in your image train did you use it and what parts before the camera.Thanks BOB

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Jerry Hyman
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Re: Edge HD Focal Reducer new [Re: Bill Shaheen]
      #4464382 - 03/21/11 03:09 PM

Hey Bill, it's great to see you on this forum! I will gladly take you up on that offer.

~jerry


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PiotrM
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Re: Edge HD Focal Reducer new [Re: Jerry Hyman]
      #4464511 - 03/21/11 04:06 PM

Those reducers must be screwed to the eyepiece or to the camera nosepiece. If you put it only bit further away they will reduce the image stronger adding some field curvature as well.


And one of those images states:
Quote:

a 2 inch nosepiece installed on the camera and the Antares reducer attached directly to it, which reduced the recommended 79mm spacing to 47mm and resulted in a reduction factor of approx. 0.61x.




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ewave
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Re: Edge HD Focal Reducer new [Re: PiotrM]
      #4536265 - 04/22/11 10:45 AM

OK

for the second year in a row, I asked the Celestron rep at NEAF last weekend when oh when art thou gonna come up with the promised FR for these OTA's? My response was that Celestron will offer the FRs for the C-11 & C14 Edge's first, within 3-5 months and the 8 & C9.25 Edge's late this year. I was also told that they failed to produce one FR that will be compatible with all of the different size OTAs this proved to be impossible, so they will have a separate FR for each OTA size. IMHO, due to C's track record, perhaps you can take that with a grain of salt (but still hoping).
Clear skies!


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skybsd
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Re: Edge HD Focal Reducer new [Re: ewave]
      #4536659 - 04/22/11 01:40 PM

Hi Sean,

Quote:

OK

for the second year in a row, I asked the Celestron rep at NEAF last weekend when oh when art thou gonna come up with the promised FR for these OTA's? My response was that Celestron will offer the FRs for the C-11 & C14 Edge's first, within 3-5 months and the 8 & C9.25 Edge's late this year. I was also told that they failed to produce one FR that will be compatible with all of the different size OTAs this proved to be impossible, so they will have a separate FR for each OTA size. IMHO, due to C's track record, perhaps you can take that with a grain of salt (but still hoping).
Clear skies!





Hope you had a great time at NEAF!

I'm so glad that you took the time to ask.., That position has been circulating around Celestron's discussion groups for a while now, and I was hoping / waiting for it to come to light here with more audit.

Fact is as was suggested in Eddgie's initial posts after receiving his EdgeHD-8 as well as a few others' posts on the Yahoo groups reporting unexpected measurement requirements for optical accessories installed off the visual backs, the internal optical paths and resulting focal points across the series are rather more different that was realized (by us), and basically, these internal differences are what Celestron have been struggling with in their so far unsuccessful attempts to produce a single FR designed to work across the whole range of EdgeHD scopes..,

I'm glad that at least they've accepted this and hopefully have now moved onto working on generating product..,

I feel for you all that are waiting - but hopefully it won't be as long as that..,

Regards,

skybsd


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kw6562
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Re: Edge HD Focal Reducer new [Re: ewave]
      #4537678 - 04/22/11 09:37 PM

Quote:

OK

for the second year in a row, I asked the Celestron rep at NEAF last weekend when oh when art thou gonna come up with the promised FR for these OTA's? My response was that Celestron will offer the FRs for the C-11 & C14 Edge's first, within 3-5 months and the 8 & C9.25 Edge's late this year. I was also told that they failed to produce one FR that will be compatible with all of the different size OTAs this proved to be impossible, so they will have a separate FR for each OTA size. IMHO, due to C's track record, perhaps you can take that with a grain of salt (but still hoping).
Clear skies!




Got the same story myself...he told me the FR for the 8 would be about $300. --Keith


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bradisback
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Re: Edge HD Focal Reducer new [Re: kw6562]
      #4538151 - 04/23/11 05:13 AM

Thank you Sean

Is what they told you the ratio of the reducer?


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ewave
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Re: Edge HD Focal Reducer new [Re: bradisback]
      #4538354 - 04/23/11 09:04 AM

No specifics on each individual reducer. My fear is that since Celestron took a hit on some R&D losses, these should prove to be expensive?

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skybsd
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Re: Edge HD Focal Reducer new [Re: ewave]
      #4538474 - 04/23/11 10:31 AM

Quote:

No specifics on each individual reducer. My fear is that since Celestron took a hit on some R&D losses, these should prove to be expensive?




No cause for concerns at this point - best to wait to see, really.

Regards,

skybsd


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Giuliano69
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Re: Edge HD Focal Reducer new [Re: bradisback]
      #4547981 - 04/27/11 03:31 PM

Has anyone used the Lepus focal reducer for VISUAL use ?
How it is FITTED to the ocular ? Is it threaded in the diagonal o something else ?

How to keep the correct distance between the FR and the ocular for best performance ?


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MarioCannistra
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Re: Edge HD Focal Reducer new [Re: Giuliano69]
      #4551223 - 04/29/11 09:19 AM

Here you will find some info about how the Lepus FR is attached to the scope: URL

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Giuliano69
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Re: Edge HD Focal Reducer new [Re: MarioCannistra]
      #4551796 - 04/29/11 02:42 PM

Thank Mario for your information.

I contacted Optec for an inquiry on the product,
They informed that
tehy have produced a special adapter for the 3" thread, that directly fits the lepus lens "inside" the baffle, optimizing the performance of the lens. http://dl.dropbox.com/u/26291352/coelestis/20110328%20006-1.jpg
The back focus to the camera sensor has been reduced to 100mm
the lepus FR is NOT intended for the visual use, but ONLY for photograph use. Id est no screw on diagonal or ocular...


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Donnie D
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Re: Edge HD Focal Reducer new [Re: Giuliano69]
      #4553922 - 04/30/11 06:13 PM

so, did you buy your optec adapter plate from them or from who? Will this adapter plate work with the 9.25?

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Giuliano69
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Re: Edge HD Focal Reducer new [Re: Donnie D]
      #4554945 - 05/01/11 11:27 AM

Hi Donnie,
i didn't buy the optec FR, yet.
For any HD version, there exist a specific thread adapter and a camera adapter.
This because the the back nut has different sizes (3" 1/4 for the C11 and C14) and different distance between the camera and the optec lens.
You should call the Optec directly, and ask for the part number.
Than you can give that part number to the reseller for the order.

An example of the whole system in the C14
http://dl.dropbox.com/u/26291352/coelestis/C14%20Back%20Focus-1.pdf


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jsiska
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Re: Edge HD Focal Reducer new [Re: Giuliano69]
      #4555871 - 05/01/11 08:38 PM

An advertisement for the Celestron f/6.3 focal Reducer/Corrector for Schmidt-Cassegrains reads, “…the Celestron Reducer/Corrector converts the f/10 focal ratio of Celestron C5, C8, C9¼, and C11 telescopes to f/6.3. The f/11 C14 telescope becomes an f/7.”

Does anyone recall if Celestron ever let it be known what converted focal ratios they were hoping to attain in the EdgeHD 8” and 14” OTAs when using their (vapor-ware) dedicated Reducer/(corrector???)?


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Donnie D
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Re: Edge HD Focal Reducer new [Re: jsiska]
      #4557014 - 05/02/11 12:04 PM

Thank you Giuliano for the great info. I measured the O.D. of the Rear Back Plate and it comes out to be about 3.28 "
So this means that the 9.25 HD must have the same size as the 11 and 14.

Donnie


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Nicola
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Re: Edge HD Focal Reducer new [Re: elwaine]
      #4648762 - 06/20/11 10:17 AM

Hello all,

are there any news regarding a dedicated focal reducer for the EdgeHD? I've looked around and still there doesn't seem to be any, but I hope to be wrong...

thanks
Nicola


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frolinmod
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Re: Edge HD Focal Reducer new [Re: Nicola]
      #4648914 - 06/20/11 11:28 AM

The Astro-Physics CCDT67 focal reducer works with the EdgeHD 14. I'm using it at f/7.2.

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bilgebay
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Re: Edge HD Focal Reducer new [Re: frolinmod]
      #4649219 - 06/20/11 02:04 PM

I have also purchased this for my C11 EDGE. I was not very careful when I read the subject on Ice in Space forum and missed that they were talking about C14

I will give it a try anyway now that I have it...I have spoken with Roland Christen at NEAF on this subject and according to him CCDT67 will work with f/10 scopes and up so I am quite hopeful.


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Jared
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Re: Edge HD Focal Reducer new [Re: bilgebay]
      #4650361 - 06/21/11 01:44 AM

The only catch is that it won't illuminate a very large chip.

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bilgebay
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Re: Edge HD Focal Reducer new [Re: Jared]
      #4650401 - 06/21/11 03:00 AM

I will be using this with T2i, so it should be OK, I guess Jared.

The issue I have at the moment is the spacing, IOW where to locate this reducer and what will be the new back focus distance ?

It's a pity that Celestron still didn't come up with a working solution and we have to gamble like this


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mtbdudex
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Re: Edge HD Focal Reducer new [Re: Nicola]
      #4701718 - 07/19/11 09:58 PM

Quote:

Hello all,

are there any news regarding a dedicated focal reducer for the EdgeHD? I've looked around and still there doesn't seem to be any, but I hope to be wrong...

thanks
Nicola




When I called Celestron support Thursday July 14 with some Q's about my set-up and asked about the Edge HD Focal Reducer, I was told "we have evaluated some samples but so far none have met our strict quality stds. We do expect to release the Edge HD Focal Reducer by years end".

I feel same frustration as others here.


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bradisback
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Re: Edge HD Focal Reducer new [Re: mtbdudex]
      #4702179 - 07/20/11 03:52 AM

Optec has released specific versions of the Lepus reducer ...
http://www.optecinc.com/astronomy/catalog/19407.htm

https://www.teleskop-express.de/shop/index.php/language/en/manufacturers_id/69

Stef


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jmiele
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Re: Edge HD Focal Reducer new [Re: bradisback]
      #4702349 - 07/20/11 08:44 AM

Yes, however, the image circle on the reducer is about 22mm. WAY too small to use any decent ccd camera. The minimum would be a 35mm image circle and even that will vignette a 35mm camera format full frame chip , or an STL-1100. At 35mm you can use an 8300 chip. At the 22mm Optec - I don't know what you could fit in there. Joe

Remember, that is 22mm diag, not each side.

Edited by jmiele (07/20/11 08:45 AM)


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Nocturnal
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Re: Edge HD Focal Reducer new [Re: jmiele]
      #4702373 - 07/20/11 09:01 AM

Quote:

Yes, however, the image circle on the reducer is about 22mm. WAY too small to use any decent ccd camera. The minimum would be a 35mm image circle and even that will vignette a 35mm camera format full frame chip , or an STL-1100. At 35mm you can use an 8300 chip. At the 22mm Optec - I don't know what you could fit in there. Joe

Remember, that is 22mm diag, not each side.




I think 'decent' is a relative term. I think my QHY8 is 'decent' but for you it may be completely inadequate. As this quick test from last night shows an APS-C sized chip is pretty well illuminated:

http://live.astrometry.net/status.php?job=alpha-201107-78410145

The Lepus can't make something out of nothing. If the imaging circle was (say) 40mm at F/10 it's going to be a lot smaller at F/6. The light cone is getting compressed after all. When you look into your HD scope you can see how restrictive even the native baffle tube is. Narrower than a 'regular' C. The Lepus goes right up against that, grabbing all the possible light. If your sensor is large enough that it just fits inside the F/10 light cone then you do not want to add a reducer unless you're willing to crop. The reducer will simply pull in vignetted areas and areas with poor star shapes that fall outside your sensor at F/10.


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jmiele
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Re: Edge HD Focal Reducer new [Re: Nocturnal]
      #4702427 - 07/20/11 09:37 AM

You're right, I used that term, "decent" in a less than acceptable manner. Apologies.

As to something from nothing.... The NEW Starizona Reducer/Corrector on a non Edge scope can leave you with a 35 mm image circle. That still has "slight" darkening in the corners. Like I've stated in other posts, I'm not sure what the starting flat field image circle is of the Edge design. It's not documented by Celestron. I believe because it's not even the same from 8, 9.25, 11 and 14. That being part of the reason no reducer has been produced to date. Also, the reason why, while the AP ccd compressor works with the C14 but not the other Edge scopes. At least not to the same level.

Full frame sensors are not an issue with non Edge and the Starizona compressor. The actual required image circle would be 41mm and the Starizona gives you 35mm. Just make sure folks don't get confused over the "something from nothing statement". This is only an issue with the starting point of the Edge scope, not the non Edge. That because the field has already been flattened.

Joe


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Nocturnal
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Re: Edge HD Focal Reducer new [Re: jmiele]
      #4702684 - 07/20/11 11:30 AM

That new Starizona FR looks great, thanks for letting us know about it. It was news to me. Still it doesn't work with the Edge series so I'm not sure what the relevance is for this Edge HD FR specific thread. Perhaps that it illustrates that if C had designed a larger diameter corrector/flattener for the HD series then the imaging circle would be bigger? As I said the stock HD baffle tube opening is quite a bit smaller than that of a non HD C scope (I have both).

Darkening in the corners is normal for all optical designs. The center gets more light than the edges. It's all a matter of 'how much'. That's a separate issue from star quality. I think a combination of both defines the imaging circle and even then it depends on your tolerance for both. Light falls of gradually, star quality deteriorates gradually.

My "something from nothing statement" applies to *this* discussion. I did not talk about non-Edge SCT nor about the Starizona FR. No confusion.

Regardless of what the actual imaging circle is for an Edge scope the fact remains that when you add a reducer you're going to make that imaging circle smaller. This is sometimes overlooked, hence my comment about making something out of nothing. It is my understanding that an STL-11K has a sensor that barely fits in the F/10 imaging circle. I don't have that camera so I can't verify for myself. Assuming that is true it follows that adding a reducer results in an imaging circle that does not cover that chip. That was my point. Let's discuss it without bringing in different scopes, that doesn't add anything other than "go buy a different scope". That's always an option but we're talking about FRs for Edge scopes here.


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charles genovese
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Re: Edge HD Focal Reducer new [Re: Nocturnal]
      #4702895 - 07/20/11 01:18 PM

I don't understand why there is any concern about vignetting- the word is crop.

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jmiele
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Re: Edge HD Focal Reducer new [Re: Nocturnal]
      #4703037 - 07/20/11 02:29 PM

I used the non Edge corrector as an example to point out the difference you mentioned regarding image circle impact.

The real question is WHY when a standard F/10 or 11 Celestron could already be reduced and corrected, anyone would spend 45% more to buy one that couldn't, and then be concerned they couldn't reduce the FL? It's no secret here at CN that I'm not clear on the market for this not optical system as it does less than its predisessor and cost twice the money.

Joe


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frolinmod
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Re: Edge HD Focal Reducer new [Re: jmiele]
      #4703206 - 07/20/11 04:16 PM

As the not so proud owner of an expensive EdgeHD 14 all I have to say is, "Okay Joe, rub some more salt in the wound..."

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jmiele
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Re: Edge HD Focal Reducer new [Re: frolinmod]
      #4703218 - 07/20/11 04:22 PM

I never said there was anything wrong with Edge scopes. I'm just waiting for a price drop to get one with a built in flattener.

Joe


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Re: Edge HD Focal Reducer new [Re: jmiele]
      #4703579 - 07/20/11 07:28 PM

When some of us bought out EdgeHD's almost 2 years ago, Celestron was saying the FR would be out in a matter of months which sounded reasonable. It's almost funny now that I think about it. I'm still waiting

Now when someone says "Celestron said it will be out next quarter" I take it with a grain of salt.


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ewave
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Re: Edge HD Focal Reducer new [Re: nemo129]
      #4703683 - 07/20/11 08:28 PM

Yeah, wait till next year's NEAF and ask them the same question.

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jmiele
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Re: Edge HD Focal Reducer new [Re: ewave]
      #4703701 - 07/20/11 08:43 PM

Well the 14 works with the AP 67 Compressor. Ice In Space did a review. It may also work with the 11. Sedat bought one, not sure what his findings were. Sedat? The AP piece is a compressor only. That was a point I made in another post. I don't think they will have one for all reducer.

Joe


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AaroninVermont
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Re: Edge HD Focal Reducer new [Re: jmiele]
      #4705022 - 07/21/11 03:25 PM

What's sad is that Celestron has been very "hush-hush" about the whole thing. It would behoove them to have an Edge Focal Reducer page up whereas all of us who are financially/emotionally/intellectually invested in the Edge FR could watch the up an downs of their progress.

I can't believe they are NOW saying "end of the year," which we all know is BS.

As an Attorney, my senses are tingling and this screams of breach of contract, bad faith, fraud.

I opine that Celestron has known that they would not be able to produce a Focal Reducer for their highly touted imaging-telescopes and have acted in bad faith by not disclosing their inability to produce one as they knew that such news would destroy their marketability and seriously affect sales.

Class action law suit anyone? Seriously... I love Celestron but I'm angry at how they're playing this out.

How about some pictures or data of the failed attempts, or even a sample pic of one of the many prototypes they "allege" to have attempted? Something more than... "end of the year."

Sorry to rant... but legally speaking and under the Uniform Commercial Code (that governs Celestron), it's not alright how they're handling this and their loyal customers deserve to be treated better instead of being strung along like sheep.


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Mike Wiles
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Re: Edge HD Focal Reducer new [Re: AaroninVermont]
      #4705161 - 07/21/11 04:47 PM

Quote:

Class action law suit anyone? Seriously... I love Celestron but I'm angry at how they're playing this out.



Nothing helps speed the introduction of a long awaited product better than a class action lawsuit.

I'm sitting and waiting for the reducer as much as anyone else. The fact of the matter is that these are very capable scopes for astrophotography at f/10 and they're very capable scopes for astrophotography at f/2. Maybe we could also file a class action since they continue to advertise that they're "Fastar compatible" but they stopped making the Fastar lens years ago.

There have been other people who have tested with other reducers, some with very good results. From what I've seen, the Optec Lepus reducer is an extremely viable alternative - at least for the 11" scope. Also, if history has taught us anything it's that when there's a market being underserved - some vendor will step in and serve that market.

Think of how much astrophotography we'd have done already if we'd been imaging at f/10 for the last year while we wait. I'm confident that someone will turn up a viable, useable reducer soon.

Mike


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Re: Edge HD Focal Reducer new [Re: jmiele]
      #4705318 - 07/21/11 05:57 PM

Quote:

Yes, however, the image circle on the reducer is about 22mm. WAY too small to use any decent ccd camera. The minimum would be a 35mm image circle and even that will vignette a 35mm camera format full frame chip , or an STL-1100. At 35mm you can use an 8300 chip. At the 22mm Optec - I don't know what you could fit in there. Joe

Remember, that is 22mm diag, not each side.




It seems that many EdgeHD owners expect a miracle from Celestron. The EdgeHD illuminates a 40mm circle. Any focal reducer will reduce that image circle. You can estimate the size of the fully iluminated circle by multiplying the reduction factor by the nominal imaging circle diameter. E.g. a 0.75x FR will iluminate 0.75 * 40mm = 30mm circle; a 0.63 FR will illuminate 0.63*40mm = 25mm circle. The well corrected image circle might be even smaller. The EdgeHD with a FR will not be better than a conventional SCT with a FR.


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jmiele
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Re: Edge HD Focal Reducer new [Re: Alph]
      #4705450 - 07/21/11 07:15 PM

Mike, The Lepus leaves you a 22mm image circle. Too small IMO.. As to class action, if people continue to accept the Celestron ways, they'll have no reason to change.

Alph, And a flat field standard reduced to f/7 leaves a 35mm image circle. And the standard Fastar works the same. I don't expect miracles, I expect "something" more for a 45% premium. So, either you didn't read the entire post, or you are trolling for trouble.

Joe


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Mike Wiles
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Re: Edge HD Focal Reducer new [Re: jmiele]
      #4705559 - 07/21/11 08:24 PM

Quote:

Mike, The Lepus leaves you a 22mm image circle. Too small IMO.. As to class action, if people continue to accept the Celestron ways, they'll have no reason to change.




I agree about the Lepus - thus the reason I haven't purchased my own yet. Earlier in this thread I believe, there were some images taken with a QHY8 camera which is a true APS-C sized chip and while there was some vignetting for sure, it appeared that a decent set of flats would address the issue. Like you though, I remain not entirely convinced. That....and I'm still having enough fun at f/2 with Hyperstar that the lack of a reducer isn't much of an issue to me (yet).

Mike


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frolinmod
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Re: Edge HD Focal Reducer new [Re: AaroninVermont]
      #4705935 - 07/22/11 12:11 AM

Quote:

I can't believe they are NOW saying "end of the year," which we all know is BS.



Saying, "next year" is equivalent to saying "go away son, you bother me."


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bilgebay
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Re: Edge HD Focal Reducer new [Re: jmiele]
      #4706115 - 07/22/11 04:26 AM

Quote:

Well the 14 works with the AP 67 Compressor. Ice In Space did a review. It may also work with the 11. Sedat bought one, not sure what his findings were. Sedat? The AP piece is a compressor only. That was a point I made in another post. I don't think they will have one for all reducer.

Joe




Joe, I didn't have time to test the AP67 yet. Maybe this weekend.

Cheers

Sedat


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bilgebay
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Re: Edge HD Focal Reducer new [Re: Mike Wiles]
      #4706122 - 07/22/11 04:37 AM

Quote:

and I'm still having enough fun at f/2 with Hyperstar that the lack of a reducer isn't much of an issue to me (yet).

Mike




Mike, now that you have tasted the sweet Hyperstar potion, you will never be happy with anything slower. I plan to go ahead with mosaics for wider FOV instead of using anything slower. Maybe a fast Newtonian Astrograph can be an option I can think about.

Cheers


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jmiele
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Re: Edge HD Focal Reducer new [Re: bilgebay]
      #4706383 - 07/22/11 09:58 AM

Ok Sedat. I think many would be interested in the performance. Not sure what size chip you are using to image with, but knowing that when hearing your results would also be helpful. I will also see what a can find around the internet. It's will be 100F here today and I will be looking for a slow moving task to occupy my time.
Thanks.. Joe


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AaroninVermont
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Re: Edge HD Focal Reducer new [Re: Mike Wiles]
      #4711941 - 07/25/11 01:26 PM

Quote:

Quote:

Class action law suit anyone? Seriously... I love Celestron but I'm angry at how they're playing this out.



Nothing helps speed the introduction of a long awaited product better than a class action lawsuit.

I'm sitting and waiting for the reducer as much as anyone else. The fact of the matter is that these are very capable scopes for astrophotography at f/10 and they're very capable scopes for astrophotography at f/2. Maybe we could also file a class action since they continue to advertise that they're "Fastar compatible" but they stopped making the Fastar lens years ago.

There have been other people who have tested with other reducers, some with very good results. From what I've seen, the Optec Lepus reducer is an extremely viable alternative - at least for the 11" scope. Also, if history has taught us anything it's that when there's a market being underserved - some vendor will step in and serve that market.

Think of how much astrophotography we'd have done already if we'd been imaging at f/10 for the last year while we wait. I'm confident that someone will turn up a viable, useable reducer soon.

Mike




Mike,

The POINT is that my purchase and probably hundreds more relied on their promise to release a Focal Reducer. I have no interest in imaging at F/10 and if I wanted to image at F/2, I would have bought an 80mm refractor, which gives the same FOV.

If Celestron would have been honest and said: "look, we're struggling to make an FR for this buyer beware!" I and surely others would have opted for another route. This is called "dettrimental reliance" or "promissory estoppel."

Class actions aren't about motivating someone to do something. Rather, it's about being financially compensated for the "actual value" of something in its current condition as opposed to the value of that same something with the condition (focal reducer) promised.

Meaning, we all paid more for the promise of a focal reducer, and we should have paid less because they can't make a focal reducer.

I think that every single Edge owner should receive a refund of one thousand dollars ($1,000.00).


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phanfave
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Re: Edge HD Focal Reducer new [Re: AaroninVermont]
      #4712283 - 07/25/11 04:30 PM

I considered one of these scopes when they were announced. Decided my C8 was already doing a good job. What I don't remember was any discussion of a focal reducer coming out for the Edge HDs. I do remember reading that the existing ones wouldn't work, which is why I stuck with the C8. Did I miss some literature somewhere saying a FR was being made for it? That probably would have convinced me to upgrade from the C8.

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Re: Edge HD Focal Reducer new [Re: phanfave]
      #4712321 - 07/25/11 04:48 PM

They had announced a special reducer for the Edge series of scopes would be out as soon as they had a chance to get the scopes to market. sounded like the designs were in place but they were putting all the production attention to the ota's. If a reducer can not be produced for these scopes it certainly does hurt the value of them and I would have shopped for something else. I am hoping that they are still working on final touches getting it right and will bring them out shortly.

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jmiele
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Re: Edge HD Focal Reducer new [Re: AaroninVermont]
      #4712478 - 07/25/11 06:10 PM

Quote:

Quote:

Quote:

Class action law suit anyone? Seriously... I love Celestron but I'm angry at how they're playing this out.



Nothing helps speed the introduction of a long awaited product better than a class action lawsuit.

I'm sitting and waiting for the reducer as much as anyone else. The fact of the matter is that these are very capable scopes for astrophotography at f/10 and they're very capable scopes for astrophotography at f/2. Maybe we could also file a class action since they continue to advertise that they're "Fastar compatible" but they stopped making the Fastar lens years ago.

There have been other people who have tested with other reducers, some with very good results. From what I've seen, the Optec Lepus reducer is an extremely viable alternative - at least for the 11" scope. Also, if history has taught us anything it's that when there's a market being underserved - some vendor will step in and serve that market.

Think of how much astrophotography we'd have done already if we'd been imaging at f/10 for the last year while we wait. I'm confident that someone will turn up a viable, useable reducer soon.

Mike




Mike,

The POINT is that my purchase and probably hundreds more relied on their promise to release a Focal Reducer. I have no interest in imaging at F/10 and if I wanted to image at F/2, I would have bought an 80mm refractor, which gives the same FOV.

If Celestron would have been honest and said: "look, we're struggling to make an FR for this buyer beware!" I and surely others would have opted for another route. This is called "dettrimental reliance" or "promissory estoppel."

Class actions aren't about motivating someone to do something. Rather, it's about being financially compensated for the "actual value" of something in its current condition as opposed to the value of that same something with the condition (focal reducer) promised.

Meaning, we all paid more for the promise of a focal reducer, and we should have paid less because they can't make a focal reducer.

I think that every single Edge owner should receive a refund of one thousand dollars ($1,000.00).




Well said. I agree completly, and BTW, if you wanted to image at F2 the standard can do it and for 45% less. The primary in all of these scopes is exactly the same. I had earlier on said I didn't think folks would be looking to image solely at F10. Once again, if we never react, then Celestron will never act. They will continue to do business the same until their bottom line is affected.

Joe


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phanfave
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Re: Edge HD Focal Reducer new [Re: Stew57]
      #4713782 - 07/26/11 12:41 PM

Quote:

They had announced a special reducer for the Edge series of scopes would be out as soon as they had a chance to get the scopes to market. sounded like the designs were in place but they were putting all the production attention to the ota's. If a reducer can not be produced for these scopes it certainly does hurt the value of them and I would have shopped for something else. I am hoping that they are still working on final touches getting it right and will bring them out shortly.




Yeah that's poor for Synta to do that. Here's hoping they'll still figure out how to make one (or that someone will).


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Mike Wiles
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Re: Edge HD Focal Reducer new [Re: AaroninVermont]
      #4714155 - 07/26/11 04:25 PM

Quote:

The POINT is that my purchase and probably hundreds more relied on their promise to release a Focal Reducer. I have no interest in imaging at F/10 and if I wanted to image at F/2, I would have bought an 80mm refractor, which gives the same FOV.




We just go about the way we purchase things very differently then. If my only reason for purchasing the telescope was to image at f/6.3 with a reducer....there would be no reason to purchase the scope until it was possible to image at f/6.3 with a reducer.


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jmiele
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Re: Edge HD Focal Reducer new [Re: Mike Wiles]
      #4714181 - 07/26/11 04:47 PM

That does make sense, however, Celestron did actually state that the reducer would be available soon after the scopes. That was prior to the Edge release. Also, they touted it as an imagers system. As Fastar does use the Edge components that doesn't count, right? While the field at F/10 is flat it does limit imaging targets with it's narrow FoV. Additionally, TBH, sold on their mounts, ANY of their mounts, starter imagers would want to image at F/6.3 before tackling F/10. IME, a C14 at F/10 is work on an AP900/1200 or even a Paramount ME. And I've 30 years of doing this. I'd like to think I've some experience, but I have to say it is still challenging at 3-4,000 mm of FL.

So, having the reducer would widen their market and customer appeal. Once again, they haven't made one because it will not be 1 unit. Many inside have speculated that the optical charictaristics of each Edge 8,9.25, 11 and 14 will require different correction. That is why the folks testing the AP Compressor are having luck with the C14 and not so much with the 11.

They are not bad scopes, they are different. If they meet your needs or requirements, keep one or buy one. I have no stock in Celestron. I just think they have been misleading, or ran into unexpected problems. Either way, they should better communicate with their customers who are spending 3-10 thousand dollars or their products. It's just not fair treatment. That along with their 3-4 month repair time make them an absolute nightmare of a company. Why do I have 2 C-14's? They meet my needs, however, I would toss them in the garbage before I would send to them for repair if I couldn't fix them myself. I bought them with that understanding.

Joe

edit: Sorry for another rant...but this issue just burns me up. and I'm not angry. see....

Edited by jmiele (07/26/11 04:49 PM)


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Mike Wiles
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Re: Edge HD Focal Reducer new [Re: jmiele]
      #4714307 - 07/26/11 06:10 PM

No question about it, and I agree completely with all of it. For me, talk of things like class-action lawsuits is definitely the exact opposite of the way I'd like to spend my astronomy related time. I bought my Edge HD to image at f/2 and eventually image at f/6.3 (or whatever the eventual reducer provides). I also bought it to use visually at f/10 - which I've done exactly twice now . At some point, I'll run out of things to image at f/2 and if there's no reducer available at that time - I'll sell the Edge HD and move to a different scope.

Here's the problem with that though - how many options are there to image at 1800-2000mm focal length with a coma free, flat field at any sort of 'fast' f/ratio? There aren't any. The best bets are the Astro-Tech RC's - but they're not burning up CCD chips at f/8 and there's no reducer available for them either. A guy could go with a traditional SCT and the Starizona SCT corrector - but again, at f/7.5 it's still awful slow.

So when the time comes, if there's no suitable reducer available, I'll probably go to the Astro-Tech RC's myself. I'm very confident that we'll have a reducer soon though. If not from Celestron, then from another source.

Mike


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jmiele
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Re: Edge HD Focal Reducer new [Re: Mike Wiles]
      #4714327 - 07/26/11 06:23 PM

No doubt Mike. Large aperture and F/7 or so equal, well, RCOS/Planewave and the like. $$$ mega bucks. So there is value in the mass produced scopes. And that's why I have a few.

However, when I think that someone waits for months or years to save for one of these and then a problem (even brand new on receipt) results in their money gone and the scope away for months, I want to scream. I do not like Goliath beating up on fellow astronomers. I know I'm preaching to the choir.


Joe


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PiotrM
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Re: Edge HD Focal Reducer new [Re: jmiele]
      #4714470 - 07/26/11 07:34 PM

There are reducers for the GSO / AT RC scopes

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Greg Boynton
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Re: Edge HD Focal Reducer new [Re: PiotrM]
      #4725707 - 08/01/11 10:47 PM

Would it be easier to design a barlow system for hyperstar to get to around F4/5? Have F2/F5 and F10 all well corrected. It seems like barlowing hyperstar would give much better illumination at F5 and a more useful image scale. Just curious

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Peter in Reno
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Re: Edge HD Focal Reducer new [Re: Greg Boynton]
      #4725773 - 08/01/11 11:25 PM

It's funny that when EdgeHD first came out, people complained that focal reducers are not yet available for this scope.

When Meade first introduced their ACF scopes, I don't recall anyone complaining about no focal reducer. Meade said their focal reducers are not recommended for ACF scopes. See this link about not for ACF scopes ("Not for ACF optical systems as field correction is not needed."):

http://www.optcorp.com/product.aspx?pid=778&kw=focal%20reducer&st=2

I won't be surprised that Celestron may not ever make focal reducer since the field is already flat at F/10. How to keep the field flat with a reducer or compressor? I don't know if it's possible despite Optec's claim their compressor will work with "corrected" SCT scopes.

There is nothing wrong with imaging at F/10. As long as the signal you are imaging is above the noise level of CCD camera, it will make great images. I have image many DSOs at F/10 especially on dim DSOs.

Peter


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Stew57
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Re: Edge HD Focal Reducer new [Re: Peter in Reno]
      #4725795 - 08/01/11 11:41 PM

The difference; Celestron used the "special reducers are coming shortly after the ota's" line as a selling point.

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jmiele
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Re: Edge HD Focal Reducer new [Re: Stew57]
      #4725850 - 08/02/11 12:25 AM

Indeed they did. It's nice to be able to shoot a wider field at reduced magnification sometimes. They've sold many of the Edge and those users should have that available to them.

As to Meade users not complaining, as pointed out they at least didn't sell it up front. Additionally, does anyone know the numbers? Edge vs. ACF? How many where sold?

Joe


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Re: Edge HD Focal Reducer new [Re: jmiele]
      #4726561 - 08/02/11 12:58 PM

I don't know why C cannot make a Reducer for their Hedge HD 8", where Vixen can do one for their flat field VC 200L (F9 to F6,4). Is it so hard to reduce a flat field ?
Anybody to try this vixen Reducer on a hedge 8" ?


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Re: Edge HD Focal Reducer new [Re: jean-jack]
      #4727217 - 08/02/11 08:39 PM

One of British shops commented on SGL forums that production in China is stalling a bit. That may affect how much scopes Synta makes, and also how much time and money their R&D department will use. They announced for 2011: 5-element APOs (not quite here), EQ7 (no news), big dobsonians (delivered), carbon fibre Newtonians (delivered) and so on. Seems like no time left for the SCT branch (except EdgeHD tube design for some C14). As you can see they focused on astrographs (Newts and APOs) + big dobs for demanding visual observers.

It's either that EdgeHD sales wasn't so high to do more in that direction for 2011, or... it's impossible to do a better (wider circle) reducer than those Optec Lupus units (and Celestron is rather more Hyperstar than reducer oriented).

So maybe after 2011 development - customer demand will put EdgeHD or plain SCT components on the list for 2012. if it's doable.


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Re: Edge HD Focal Reducer new [Re: PiotrM]
      #4727229 - 08/02/11 08:48 PM

Does anyone know how the Optec reducer mounts to EdgeHD? Does it screw directly to the rear cell or do you have to get SCT to 2" barrel with compression ring?

Any good pictures of Optec compressor or reducer? I can't find good pictures.

Thanks,
Peter


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Re: Edge HD Focal Reducer new [Re: AaroninVermont]
      #4727416 - 08/02/11 10:53 PM

Aaron, I agree 100%. I bought my 14" EdgeHD on Astromart, but the promise of a focal reducer "coming soon" from Celestron's website was definitely part of my decision to buy. (Wonder if I could still be part of the class?).

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Re: Edge HD Focal Reducer new [Re: Stew57]
      #4727980 - 08/03/11 11:12 AM

Quote:

The difference; Celestron used the "special reducers are coming shortly after the ota's" line as a selling point.




Which was the primary reason I sold my EdgeHD 9.25". No
reducer would work on it. The Optec unit works on the 11"
version, and that seems to be enough for Celestron to think
that they don't need to come through on the promise. It
did not work on the 9.25" version, and left me in a hole
I had to sell the scope to get out of. I have a 12" ACF now
that seems to work with a variety of reducers, but had I
known the EdgeHD would not work, I could have saved some
money by making the right choice in the first place.

Tom


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Re: Edge HD Focal Reducer new [Re: Thomas A Davis]
      #4728050 - 08/03/11 11:49 AM

Did anyone ever tried to use Celestron F/6.3 focal reducer on their EdgeHD scope and see how well it works?

Have you tried imaging at F/10? It works well for me in my CPC0800. As long as the exposure is long enough for the signal of the target DSO is above the noise level of CCD, it should work fine. CCD sensors are quite sensitive nowadays. See my images in my gallery. Some images were taken at F/10 like NGC4565, NGC7331, M51, M106, NGC6946, M16, M20, M27, M57 and NGC6781.

Peter


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Re: Edge HD Focal Reducer new [Re: Peter in Reno]
      #4728094 - 08/03/11 12:09 PM

Every time this thread gets bumped up to the top my heart skips a beat because I think "finally some good news!"

@Peter in Reno, the Celestron F/6.3 is a corrected reducer for uncorrected Celestron SCTs. By corrected I mean flat field. The EdgeHD line has a flat field so by using a corrected reducer you introduce the issues back in again.


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Re: Edge HD Focal Reducer new [Re: Micheal]
      #4728105 - 08/03/11 12:14 PM

This shows a Lepus mounted on an HD 11:

http://gallery.tungstentech.com/main.php?g2_itemId=2272

I think results are decent but you can see the star shapes deteriorate at the edges. If you want to take shorter exposures for less detailed images and you don't mind cropping a little this reducer may work. You will probably want to re-collimate the scope after mounting the reducer and leave things alone if you can. I think the reducer is mechanically sound but whenever you add these types of components there is a chance you can introduce a slight bit of tilt.

I took two more test images last night but I need to take a look at them to ensure whatever artifacts it shows are because of the reducer and not other problems.


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Re: Edge HD Focal Reducer new [Re: Micheal]
      #4728149 - 08/03/11 12:38 PM

Quote:

@Peter in Reno, the Celestron F/6.3 is a corrected reducer for uncorrected Celestron SCTs. By corrected I mean flat field. The EdgeHD line has a flat field so by using a corrected reducer you introduce the issues back in again.




I am aware of that. I was just curious what the image looks like with regular Celestron focal reducer and EdgeHD. It can't be that bad. You probably have to crop a little bit more than usual.

Yes, I read the whole thread. Sometimes it's easy to forget if someone already posted a similar question as mine.

I ordered 8" EdgeHD because I believe it does a better job flattening at F/10 than Meade ACF since Meade SCTs only corrects coma but not curvature. EdgeHD scopes deal with both coma and field curvature. Also I want an SCT with mirror locks.

Peter


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Re: Edge HD Focal Reducer new [Re: Nocturnal]
      #4728161 - 08/03/11 12:45 PM

Quote:

This shows a Lepus mounted on an HD 11:

http://gallery.tungstentech.com/main.php?g2_itemId=2272




Thanks Sander. Can you describe how this reducer is mounted? Will it work with C-8 since C-8 has a smaller opening than C-9.25 and larger? I asking about physical mounting of Optec reducer to C-8, not performance of the reducer.

I use Hutech OAG and need to fit this OAG to reducer. Is the back of Optec reducer T-Thread or SCT thread? I prefer SCT thread.

Thanks,
Peter

Edited by Peter in Reno (08/03/11 12:49 PM)


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Re: Edge HD Focal Reducer new [Re: Peter in Reno]
      #4728189 - 08/03/11 12:57 PM

Hi Peter,

the reducer is a loose item that gets compressed against the back of the telescope with the orange nut you see in the pictures. There is a spacer ring that goes between the reducer and the scope. The black tube you see get attached to the reducer with 3 set screws. It's all quite solid. Indeed that ring does not fit the HD8 but as you've no doubt seen on the Optec site they make one for the HD8 so I don't see why this would be an issue. The optec site also lists all the adapters they have you can attach to the back of the reducer. If what you need isn't available I'd send them an email. I did and got a reply the next day. I think you'll agree their words are a lot better than my speculation about parts availability


http://www.optecinc.com/astronomy/catalog/19407.htm


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Re: Edge HD Focal Reducer new [Re: Nocturnal]
      #4728217 - 08/03/11 01:11 PM

Thanks again Sander for the link. I wish Optec were less camera shy and post pictures of their products.

I have faith in Celestron and they will produce focal reducers. If they say that focal reducer will be made, then I believe that will happen, the question is when. I hope they will thoroughly test them for all EdgeHDs before delivering to the public. I would rather wait a little longer and get the reducer working the first time.

Peter


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Re: Edge HD Focal Reducer new [Re: Peter in Reno]
      #4728235 - 08/03/11 01:16 PM

I agree it would be nice if Optec displayed their products a bit more glamorously. There's no such thing as too many pictures in this day and age. Heck, add a youtube video that shows how the product gets mounted. Optec has been around for a long long time and that's perhaps holding them back a little in this regard. I also don't like the separate price list very much. Hutech does that too. Be upfront with documentation and prices for your products.

Anyway.

I also look forward to seeing the C reducer but I don't expect miracles. The best design would probably replace the built in flattener with a flattener/reducer combination. Meanwhile I'm happy with F/10 and F/2. The Lepus isn't mine but I'd get it if I was desperate for F/6.

Edited by Nocturnal (08/03/11 01:17 PM)


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Re: Edge HD Focal Reducer new [Re: Thomas A Davis]
      #4728304 - 08/03/11 02:00 PM

Quote:

I have a 12" ACF now
that seems to work with a variety of reducer




Hm... which ones do work with the ACF? On German forums people rather limit the choices to Optec reducers.


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Thomas A Davis
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Re: Edge HD Focal Reducer new [Re: PiotrM]
      #4729549 - 08/04/11 08:52 AM

Quote:

Hm... which ones do work with the ACF? On German forums people rather limit the choices to Optec reducers.




I found the Lumicon Giant Easy guider to work the best. The
Meade F/6.3 unit works for most of the field on the ACF,
but woth some coma in the corners. The Lumicon unit works
better at F/5 than the Meade (some minor coma), and no issue
at F/6.5. The advsntage to this unit is it has an 80mm lens
and makes use of the large 3" rear adapter on the scope.
I have not yet tried my .75X AP unit, so I can't report on
that as of yet.

The real concern to me with the 9.25" EdgeHD (other than
it would not work with any reducer I could find, other than
the Hyperstar unit) was the sensitivity to spacing. The
ACF, since it uses a hyperbolic secondary, instead of a
flattening lens, does not have a spacing sensitivity.

The main thing with the ACF, is not using a reducer that
is corrected for an SCT. The result is added coma. This
did not work on the EdgeHD for me, since spacing with the
flattener was critical, and no adapter I could find would
make the Optec, or the AP .75X reducer I had work.

Optec was going to make an adapter for the 9.25" unit, but
simply refunded my money instead.

Tom


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Re: Edge HD Focal Reducer new [Re: Thomas A Davis]
      #4729561 - 08/04/11 09:00 AM

I'm surprised to read that the GEG delivers acceptable results with the ACF. That reducer lens is an achromat and I'd expect it to introduce quite bit of color fringing. I have one but it doesn't work as an OAG with the Edge as the pick-up prism doesn't extend far enough into the light cone. It probably misses it altogether.

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Thomas A Davis
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Re: Edge HD Focal Reducer new [Re: Nocturnal]
      #4729571 - 08/04/11 09:08 AM

Here's a shot of M22 taken low in the sky in Vermont at
Stellafane last weekend at the F/5 setting (actually a bit
less, since the 2" AP camera adapter increases the spacing,
theoretically making the coma worse). No color correction
issues I can see with it. The image is full frame at 50%
size. Figure less of an issue at F/6.5.

Link to M22 Image

Tom


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Re: Edge HD Focal Reducer new [Re: Thomas A Davis]
      #4729638 - 08/04/11 10:02 AM

You are right, color looks good. Star shape not so much but that's probably because like with any reducer you're pulling the outside areas inward and those outside areas are less corrected.

generally if a sensor covers the entire well corrected imaging circle at native focal length then you might as well bin to trade resolution for sensitivity rather than using a reducer. Of course this only works with monochrome cameras.


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Thomas A Davis
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Re: Edge HD Focal Reducer new [Re: Nocturnal]
      #4729655 - 08/04/11 10:15 AM

The amount of coma at less than F/5 is really not that bad
to me. More an issue of how low in the sky the object was
than correction issues. This was a DSLR shot, so no binning
possible. and it was full frame. If I tried this unit on
an EdgeHD, the results would have been horrible. I'll post
an F/6.5 shot when I get one done. That should make the
point as to whether this works or not.

Tom


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jmiele
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Re: Edge HD Focal Reducer new [Re: Thomas A Davis]
      #4729687 - 08/04/11 10:32 AM

So Tom that is not a crop? Also, what did the flats look like? Was their much vignetting?

Joe


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AaroninVermont
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Re: Edge HD Focal Reducer new [Re: Thomas A Davis]
      #4729734 - 08/04/11 11:04 AM

Quote:

The amount of coma at less than F/5 is really not that bad
to me. More an issue of how low in the sky the object was
than correction issues. This was a DSLR shot, so no binning
possible. and it was full frame. If I tried this unit on
an EdgeHD, the results would have been horrible. I'll post
an F/6.5 shot when I get one done. That should make the
point as to whether this works or not.

Tom




Great... go post these under the Meade ACF Focal Reducer thread. Took me a few minutes to figure out that these were not taken on an EDGE HD.

You got me all excited for a mintue.


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Thomas A Davis
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Re: Edge HD Focal Reducer new [Re: jmiele]
      #4729940 - 08/04/11 01:18 PM

Joe,

No, full frame. Yes, there is some vignetting, but nothing
was done here on this image to address it. A simple flat
field image would easily address what vignetting there is.
At F/6.5, I don't believe there would be an issue. The 80mm
lens, and the lower amount of restriction using the large
rear adapter on the scope, makes for vignetting less of an
issue.

Tom


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jmiele
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Re: Edge HD Focal Reducer new [Re: Thomas A Davis]
      #4730014 - 08/04/11 02:01 PM

Ok Thanks.. Joe

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Re: Edge HD Focal Reducer new [Re: Alph]
      #4734386 - 08/06/11 10:53 PM

Quote:

The EdgeHD with a FR will not be better than a conventional SCT with a FR.




It will be even worse! It is quite difficult to make a reductor for already flat-field and coma-free system.


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Re: Edge HD Focal Reducer new [Re: ValeryD]
      #4734476 - 08/06/11 11:57 PM

They really thought this one out well.. So disappointing.. Joe

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Peter in Reno
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Re: Edge HD Focal Reducer new [Re: jmiele]
      #4734512 - 08/07/11 12:34 AM

Can anyone prove that focal reducer or compressor is not possible for corrected SCTs? It seems like those who say that's not possible is more like pure speculation.

Peter


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Re: Edge HD Focal Reducer new [Re: Peter in Reno]
      #4734552 - 08/07/11 01:31 AM

Well, they don't have one. I have said all along it was possible, however, IMO would require a specific element set for each of the Edge scopes. Not one size fits all. I think that ties back to Valery's point exactly. It is difficult and most likely specific to each optical configuration. For instance, the C-14 is F/11 not F/10.

Of course it can be done. The AP compressor works with the C-14 Edge now. The jury is still out on the C-11. I think Sedat is testing one out, but I've not heard from Turkey in some time. I get nervous when I don't hear from Sedat for a while. I think he's fallen off that cliff next to his peir.

Joe


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Peter in Reno
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Re: Edge HD Focal Reducer new [Re: jmiele]
      #4734574 - 08/07/11 02:14 AM

Celestron may not have one at the moment but that does not mean they are not working on them. Have faith.

In the mean time, try imaging at F/10. There are lots of DSOs to image at F/10 like M27, M57, M51, etc.

Peter


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Thomas A Davis
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Re: Edge HD Focal Reducer new [Re: Peter in Reno]
      #4735856 - 08/07/11 08:54 PM

The basic problem is that a reducer would have to be made
specific to each model. The optical correction needed to
match each flattener lens on the EdgeHD series is different.

What I would expect is one for perhaps the 11" version
(which seems to most popular), and maybe one for some of
the other models later on. To make one that works on all
models is not readily possible. If it could have been done,
we would have seen it already. By choosing to use a
dedicated flattener lens as part of the design, Celestron
painted themselves into a corner. If they had made it a
removeable lens, and created a specific flattener/reducer
as a replacement, that would have proved much easier to do.

Since the optical formula on each model is different for
the flattener, producing a one-size-fits-all reducer
becomes a designer's nightmare.

Tom


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Re: Edge HD Focal Reducer new [Re: Thomas A Davis]
      #4735969 - 08/07/11 10:02 PM

celestron has been saying this very thing for a couple of years now. I emailed them right after getting my scope (C11hd) and they stated they were working on seperate reducers for each model. Where are they? They can't seem to make a reducer that works for any model.

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Re: Edge HD Focal Reducer new [Re: Stew57]
      #4736065 - 08/07/11 11:02 PM

Once again I am seeing speculation that Celestron will never make focal reducers. I'm all for speculation depending on the subject. This kind of speculation should not be tolerated.

I am sure Celestron is not stupid not to attempt to make focal reducers. As for any brand new products or design, they always take a lot longer than anticipated. Also, it may take time to thoroughly test them to make sure they actually work before selling them to the public. I would rather wait till they get it done right the first time than get it now and works at mediocre performance.

What if they eventually actually deliver focal reducers, will you apologize for speculating that they will never deliver them?

Celestron made the following comments on their web site:

A similar situation exists for the production and first availability of EdgeHD focal reducers. Celestron wants to assure that they will be the same high quality as the EdgeHD telescopes and won’t compromise this goal to rush them on to the market.

Peter


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jmiele
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Re: Edge HD Focal Reducer new [Re: Peter in Reno]
      #4736162 - 08/08/11 12:02 AM

Have to disagree Peter. Celestron should have made the appropriate changes to their photographic accessories _before_ releasing a product sold as a astrophotographer telescope.

As far a not speculating, or this type speculation not being tolerated, I'm not sure what you're thinking there. This is _exactly_ the type speculating that takes place when a company practices business in such a manner. Their website response is a _direct_ response to this type discussion.

To keep the analogy "optically" I'll just say, when you pickup your new car and they deliver it with no windshield I don't suppose you'll be looking to accept it. As such, there is NO reason to tolerate this either.

Joe


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Re: Edge HD Focal Reducer new [Re: jmiele]
      #4736175 - 08/08/11 12:11 AM

Quote:

Have to disagree Peter. Celestron should have made the appropriate changes to their photographic accessories _before_ releasing a product sold as a astrophotographer telescope.




Joe,

I understand your frustration, but that's an opinion on which reasonable people can disagree. While the absence of the reducer is certainly less than ideal, what is the better scenario? Having access to the Edge HD line without the reducer or not having access access to the line until the reducer is available? While some might not want the Edge HD without the reducer, clearly many do. And I can't see how we are worse off as a result.


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Re: Edge HD Focal Reducer new [Re: cbwerner]
      #4736187 - 08/08/11 12:18 AM

As has been discussed by both myself and Jim Barnett repeatedly, the standard line works JUST as well flattened, corrected or both. They built in the flattener and increased the price 45%. They additionally left there customers unable to reduce their narrow field "photographic" telescopes. To be honest, I don't get anyone defending them. I guess that's why they continue to practice business this way. You all defend their actions. Curious.. Joe

Edited by jmiele (08/08/11 12:34 AM)


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Re: Edge HD Focal Reducer new [Re: jmiele]
      #4736204 - 08/08/11 12:30 AM

When you last said they doubled the price I checked and the HD OTA was about 45% more expensive, less with the sale going on now. I let it be at the time as the discussion wasn't really going anywhere. Now you're saying it again. I don't think 45% qualifies as 'double the price'. Did I look at the wrong numbers?

At the moment Amazon lists the HD 11 for about $3100, C11 OTA with CGE dovetail about $2400. Forget for a moment that the C11 needs a $300 hyperstar adapter to make it even remotely comparable to an Edge and the Edge isn't near double the price.

Value propositions are opinions but prices are not.


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jrcrillyAdministrator
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Re: Edge HD Focal Reducer new [Re: jmiele]
      #4736218 - 08/08/11 12:35 AM

Quote:

To be honest, I don't get anyone defending them.




I don't understand why anyone would attack them. If they offer a product or feature you don't want, don't buy one. I know that I don't want one, and I don't plan to buy one. I see no need to be angry at them about that. After all, nearly every telescope on the market fits that description (meaning that it's a product that I won't be buying) and I don't have enough energy to be mad at everyone in the industry for offering something I don't need.


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Re: Edge HD Focal Reducer new [Re: Nocturnal]
      #4736221 - 08/08/11 12:36 AM

Agreed. I edited my post. I actually did know that in a much earlier thread I had actually done the math and it was exactly 45% across the line pre-sale pricing. Thanks for spotting that. Joe

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Re: Edge HD Focal Reducer new [Re: jmiele]
      #4736227 - 08/08/11 12:40 AM

Joe,

Sorry I offended. But you misread my post in seeing a defense of Celestron; I took no position other than that the market votes and I don't see how we are harmed by having one more thing to vote on.

I'm well aware of your and Jim's position on the flattening. I haven't bought an Edge HD nor would I intend to do so. So I vote no as you presumably have. Others have voted differently. I didn't state the former above of course, but neither did I make a defense of Celestron - I only pointed out that many are buying these scopes - though there are also suggestions of excess inventory perhaps signaling slower than anticipated sales.

Regardless, I'm not your adversary. And we can wish Celestron would stage things differently without needing them or anyone else to be an adversary. They're in business to make a profit. Maybe they will with this product. And maybe (watch me - I'm gonna date myself) this is their New Coke moment.

EDIT: Not sure if the sequence appears odd, but this post was written before seeing John's and Joe's intervening posts.

Edited by cbwerner (08/08/11 12:43 AM)


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Re: Edge HD Focal Reducer new [Re: cbwerner]
      #4736246 - 08/08/11 12:52 AM

It's all good Chris. I have tended to be overly critical of them from time to time. Maybe it's because I expect more from them. I also have never been keen on the little guy getting stepped on. The David and Goliath thing was big for me.

Hopefully they do correct things (pun intended) and get folks the tools they want to use this gear. In many posts I've always been clear I don't think the Edge scopes bad - at all. Maybe just less advantages than they were originally made out to be. When this issue is corrected maybe we can see side by side if it's better to correct then compress or do both together.

Same here I did not mean to offend anyone - more than usual anyway.

Joe


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cbwerner
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Re: Edge HD Focal Reducer new [Re: jmiele]
      #4736255 - 08/08/11 12:57 AM

Quote:

Same here I did not mean to offend anyone - more than usual anyway.




A kindred spirit!


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Nocturnal
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Re: Edge HD Focal Reducer new [Re: jmiele]
      #4736259 - 08/08/11 12:59 AM

Quote:

Agreed. I edited my post. I actually did know that in a much earlier thread I had actually done the math and it was exactly 45% across the line pre-sale pricing. Thanks for spotting that. Joe




Thanks Joe


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Nocturnal
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Re: Edge HD Focal Reducer new [Re: Nocturnal]
      #4736274 - 08/08/11 01:07 AM

Here are two more Lepus shots I took the other night. Just stacked, not flattened so you can see vignetting. I took two shots to examine the reliability of the mechanical parts. There was some concern that it would be hard to attach the Lepus at the same angle each time. It seems to me this fear is ungrounded. When you tighten the large nut the Lepus gets pushed into position and I can't see it deviate much from there. Of course someone else with this reducer is welcome to repeat the test and see if their results are different.

I think these images show slight artifacts in the corners. Star quality is better at F/10. It may still be worth it for some targets to reduce the resolution and get more light per pixel. There's that value proposition again.


http://live.astrometry.net/status.php?job=alpha-201108-50449406

and

http://live.astrometry.net/status.php?job=alpha-201108-07756997

These are two 4 minute exposures, 4 x 1m only. I had some guiding issues and had to discard 1 of 5 on each.


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jmiele
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Re: Edge HD Focal Reducer new [Re: Nocturnal]
      #4736282 - 08/08/11 01:12 AM

What size chip is that? What camera? 8300 chip? The Optec only give a 22mm image circle. Have you tried a Starizona? You would get a 35mm image circle. The 8300 fits nicely into it.. Joe

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Nocturnal
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Re: Edge HD Focal Reducer new [Re: jmiele]
      #4736290 - 08/08/11 01:21 AM

It's the QHY8 in my signature, a little larger than an 8300. I wanted a flat long FL scope which is why I bought the Edge. The new Starizona reducer would have been nice but it came too late and doesn't really suit my needs. I was testing the Lepus for a friend, it isn't mine. I may still buy one but I'm not in a hurry.

Meanwhile my C11 is for sale if anyone would like to get a Starizona reducer for it


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Stew57
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Re: Edge HD Focal Reducer new [Re: Nocturnal]
      #4736552 - 08/08/11 08:45 AM

I think the point missing is not that they don't have a reducer but the marketing that, before they even had the hd's for sale (preorder only), they stated they would have a matching reducer out shortly after the scopes. I guess we can all disagree on what shortly means, but every email I have had with then they would always say a couple of months. now 2 years later I am a little sceptical of the reducers coming out soon. They should have just stated that the hd's were coming out and sometime in the future they would try and bring out a reducer.
Not really found of the windshield analogy but more like; We are bringing a specialhybrid car to market with special batteries. Preorder now and we will bring the batteries out shortly after car production. Meanwhile you can run them on gas. 2 years waiting for the batteries with no clear market schedule from the company and seemingly lots of development problems.


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Peter in Reno
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Re: Edge HD Focal Reducer new [Re: Stew57]
      #4736672 - 08/08/11 09:59 AM

Wow, it proves that focal reducer or compressor does work with "corrected" SCT. It looks better than my regular C-8 with focal reducer. I look forward to Celestron new EdgeHD reducer with SCT threads at both ends like regular focal reducer.

Peter


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Thomas A Davis
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Re: Edge HD Focal Reducer new [Re: cbwerner]
      #4737172 - 08/08/11 02:41 PM

I think the real issue of concern is that buyers, like
myself, bought the EdgeHD with the understanding that they
would release a reducer for each model, and in a timely
manner. Their failure to do so, well over a year after
that promise, with no release date on the horizon, is a
valid point of concern.

In my case, I sold it, but lost money in the process. I
replaced it with a Meade ACF 12", for which I have a
reducer that works. Had I known ahead of time that
Celestron would not come through on their promise within
a reasonable period of time, I would not have purchased
the product, and either purchased a standard Celestron SCT
(which reducers do work on), or a Mease ACF (which has
better than standard edge correction, and can be reduced
in F/Ratio). Am I angry at Celestron? No, but I am
disappointed.

Tom


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Nicola
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Re: Edge HD Focal Reducer new [Re: Thomas A Davis]
      #4742052 - 08/11/11 08:52 AM

Is there room for you for a class action?

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Thomas A Davis
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Re: Edge HD Focal Reducer new [Re: Nicola]
      #4742189 - 08/11/11 10:26 AM

Not worth the effort. Celestron, to my mind was guilty of
false, or at least misleading advertising, but intent to
deliberately mislead would have to be proven, and I doubt
that there was any such intent. This sort of thing has
happened with multiple companies in this industry, and
in almost every case, the company has really thought they
would provide what was promised. I think Celestron had
felt they could provide a reducer, but bit off more than
they could chew on this one.

If there is a lesson in this, it is not to buy a product
until all the accessories you need for it are in place, and
available. Suing is not the answer to me. Just learn the
lesson, and don't get into the position again.

Tom


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jmiele
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Re: Edge HD Focal Reducer new [Re: Thomas A Davis]
      #4742308 - 08/11/11 11:39 AM

I agree, they have shown bad form on this but no chance to make/prove deliberate intent to mislead. The only way to fix they things is educate (take it up in the forums) and stop buying their products. My problem is my compulsion for shiny things doesn't permit me not having one of everything.

Joe


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cbwerner
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Re: Edge HD Focal Reducer new [Re: jmiele]
      #4743392 - 08/11/11 11:59 PM

Yeah, while it's tempting to see intent in bad form, it's usually the result of bad execution, bad luck, and over-optimism, with a dash or two of bad management thrown in - in this case a big dash given the obvious subsequent failure to communicate on the delay.

I wasn't previously aware of the prerelease marketing about the focal reducer. While I do doubt malice of intent by Celestron, it sure makes them look stupid and I now understand better the passion some of you feel.

When you screw up, like they did in the communication here, the only good path is to man up, admit it, and set a new expectation. Silence is the worst strategy as it just fuels feelings of resentment and the belief that you're evil. People avoid admitting these things for fear of looking bad or dealing with the anger of their customers etc., but hey - wake up and smell the canine excrement - accidents smell the worst when you don't clean them up.


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AaroninVermont
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Re: Edge HD Focal Reducer new [Re: Thomas A Davis]
      #4745902 - 08/13/11 01:23 PM

Tom,

With all due respect, I disagree with just about everything you say below:

You said: “intent to deliberately mislead would have to be proven;” “I doubt that there was any such intent.”

Nobody is saying Celestron acted criminally wrong; hence, a specific (intent) is NOT required. I like your interjection that “I doubt that there was any such intent.” This comes from the same person who a few pages back in this thread said: “speculation that Celestron won’t produce a focal reducer should not be tolerated.” Do you work for Celestron or own an enormous group of their stock?

False advertising whether “intentional” or not, is STILL false advertising-And I'm qualified to tell you it is legally wrong.

And as you said it: “I think Celestron had felt they could provide a reducer, but bit off more than they could chew on this one.”

That’s EXACTLY my point… but WHEN did they know they bit off more than they could chew? More importantly, how many Edge telescopes besides mine, did they sell AFTER they knew “they bit off more than they could chew” and it’s ok that they continued to advertise that a FR was forthcoming?

You said: “Not worth the effort. If there is a lesson in this, it is not to buy a product until all the accessories you need for it are in place, and available. Suing is not the answer to me. Just learn the lesson, and don't get into the position again.”

Well I respect your right to have your opinion, but I personally don’t take kindly to anyone pulling the wool over me and I certainly will not JUST “learn the lesson.”

Celestron has dangled a carrot in being the promised focal reducer out in front of its advertising for the Edge optical tubes. I was induced by this carrot as were likely thousands of others. And you think that all of us should just accept the bait-and-switch tactics? As an attorney, I’m having a REALLY hard time accepting your suggested “lesson.”

Lawsuits are the last/worst case scenarios…
Shouldn’t Celestron be more open to their customers who bought their Edge scopes about the Focal Reducer progress? Are we still in development? Are we going to be able to make one? Are we already in limited production? Does Celestron even know the answers to any of these questions?

Sorry, but I don’t think wanting to know the above is so wrong.

Aaron in Vermont


Quote:

Not worth the effort. Celestron, to my mind was guilty of
false, or at least misleading advertising, but intent to
deliberately mislead would have to be proven, and I doubt
that there was any such intent. This sort of thing has
happened with multiple companies in this industry, and
in almost every case, the company has really thought they
would provide what was promised. I think Celestron had
felt they could provide a reducer, but bit off more than
they could chew on this one.

If there is a lesson in this, it is not to buy a product
until all the accessories you need for it are in place, and
available. Suing is not the answer to me. Just learn the
lesson, and don't get into the position again.

Tom




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EnglishDave
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Re: Edge HD Focal Reducer new [Re: AaroninVermont]
      #4746053 - 08/13/11 02:32 PM

Personally speaking I can categorically say that the uncertainty over the FR issue has put me right off buying an Edge scope. This is a shame as I would willingly have paid the extra for the improved optics as compared with the standard SCT but only if I could be sure a dedicated FR was available (or going to be available in the very near future).
I am sure I am not the only person who has come to this conclusion...


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Thomas A Davis
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Re: Edge HD Focal Reducer new [Re: AaroninVermont]
      #4746646 - 08/13/11 09:06 PM

Aaron,

I understand the way you feel. I am not happy with what I
went through with this either. What you need to remember,
though, is I am not an attorney, and hiring one over what
I might have lost in this would never give me enough back
to make it worth it. To you, as an attorney, your view
may be different. To me, better to learn the lesson to not
believe what Celestron says they will do, and not buy from
them unless they have the actual product available and it
has been found to perform as advertised. As a non-attorney,
I'm simply taking a realistic view of my situation. It was
in no sense intended to tell you what you should do.

Thanks, Tom


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wolfman_4_ever
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Re: Edge HD Focal Reducer new [Re: Thomas A Davis]
      #4746804 - 08/13/11 10:47 PM

What's odd is Celestron still says one is coming out. This is from there support page. *sigh*


Will I be able to use my standard Celestron f/6.3 reducer/corrector with an EdgeHD?

Answer
No.

The Celestron f/6.3 reducer/corrector is designed to correct for aberrations that are not found in the new EdgeHD design. Using the present reducer/corrector may actually diminish optical quality by adding aberrations to the new scope’s performance.

Instead, use of a special EdgeHD corrector/reducer is recommended. This accessory will be available at a future date from Celestron.

Created On:

Jul 16 2009 10:43 AM

Edited by wolfman_4_ever (08/13/11 10:48 PM)


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Calypte
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Re: Edge HD Focal Reducer new [Re: wolfman_4_ever]
      #4746847 - 08/13/11 11:18 PM

Mr. Davis: The attorney will have to answer, but it seems to me it would be very difficult to bring action against Celestron, even if it were cost-effective (HE can afford to be outraged, because HE doesn't have to pay $500 just to have a pleasant 1 hr chat with an attorney). Sure, you could claim you bought an EdgeHD with the belief that a reducer would eventually become available. But: (1) the scope is usable for imaging without a reducer; (2) the scope is not otherwise significantly defective; (3) the warranty probably leaves Celestron blameless if you find the scope unsuitable for your particular tasks; (4) the warranty probably says they can change specifications without prior notice, which means, if they can't make or choose not to make a reducer, then they have effectively changed the specifications, and that possibility is covered by the warranty, which you accepted when you chose to keep the product.

If I had one of these scopes, I would try the A-P CCDT67 reducer, which is not a flattener. I've been told it'll work, and I've been told it won't work. This is easy for me to say, because I already have this reducer. I'd probably try to borrow a scope (I know one of the beta testers) to try out the combination.


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EnglishDave
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Re: Edge HD Focal Reducer new [Re: wolfman_4_ever]
      #4747616 - 08/14/11 01:06 PM

Quote:

What's odd is Celestron still says one is coming out. This is from there support page. *sigh*




The fact that their post is dated over two years ago is hardly cause for optimism...


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jmiele
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Re: Edge HD Focal Reducer new [Re: EnglishDave]
      #4747775 - 08/14/11 02:48 PM

I think I said this before, not sure, but is anyone disturbed but the fact that given all this they are now starting to make other parts of the line (CPC) with these same optics? When they still haven't serviced current Edge users.

Here's what I think, for the same reason they use the Edge casing on the standard scopes now, it's cheap to do things one way. I predict, that following this price reduction we just saw, shortly (whatever that means ) they will eliminate the standards altogether.

Joe


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Mike Wiles
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Re: Edge HD Focal Reducer new [Re: AaroninVermont]
      #4747785 - 08/14/11 02:54 PM

Quote:

False advertising whether “intentional” or not, is STILL false advertising-And I'm qualified to tell you it is legally wrong.



You're also qualified to file a class action lawsuit and represent the owners of Edge HD scopes on a pro bono basis. How about doing that? I'm guessing you're not quite THAT outraged. My experience with the legal industry has always shown that the amount of idealism is directly tied to the number of billable hours involved.

If the ONLY reason that a person bought one of these scopes was so that they could image at f/6.3 with a Celestron branded reducer - they've made a poor decision (that's the censored version) and should accept the consequences of their poor decision making process.

If one wants to put other brands of reducers to work there have been reports and there's demonstrated imagery that shows other brands of reducer working well with chips up to APS-C size. Unfortunately, that doesn't leave much to complain about. Celestron and Meade and everyone before them has a long, long, long storied history of announcing products and not delivering them for months and months or even years. That sort of behavior pretty much defined the telescope market in the 80's and 90's. I would dare say that the gap between announcement and delivery of a new product in the modern era is better than it has ever been.

Threatening a class action lawsuit as a substitute for personal accountability is just silly. I reiterate that if the only reason that a person bought this scope was to image at f/6.3 with a Celestron reducer - then they KNEW at the time of purchase that they were buying something that they couldn't use. They WILLFULLY and with full knowledge made that decision at the time. Live with it.

And Aaron - this isn't so much directed at you (just the bit about using your attorney powers to put your efforts where your opinions are) as it is at the small group that seems to add to this thread only for the purpose of complaining.


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jmiele
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Re: Edge HD Focal Reducer new [Re: Mike Wiles]
      #4747845 - 08/14/11 03:32 PM

Not so sure it complaining Mike. Expecting a company to deliver the promised accessories to fully utilize something you purchased. You know, I didn't have an Edge. I bought one solely for the purpose of being able to justify my comments towards Celestron. It's an 11. It sits in a box in the garage. I was going to sell it but then decided to wait.

Joe


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nemo129
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Re: Edge HD Focal Reducer new [Re: jmiele]
      #4747882 - 08/14/11 04:06 PM

Couple of points here:

1) Celestron is wrong to continue to leave statements on their website promising a FR for the EdgeHD series if they are not going to produce one.
2) If Celestron is truly going to produce said FR's they should be more up front regarding the time table and treat their customers with more respect.
3) Suing Celestron is going to no one any good except the lawyers involved. They will get the lion share and everyone else will get what's left or nothing (maybe a coupon for 20% off an EP! ) That is just the way it works in our legal system.
4) If people want to complain about the situation, well that is why we have forums. If the complaining gets out of hand our gracious staff of moderators will deal with it. There is no need to make judgements about others decisions, they will have to live with their decision if it did not work out for them.

Me, I am selling My EdgeHD, not because it is a bad telescope or I cannot image with it at f/10. I am just moving on for now. Maybe someday I will buy another??


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jmiele
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Re: Edge HD Focal Reducer new [Re: nemo129]
      #4747930 - 08/14/11 04:36 PM

I saw that Kirk. I thought that was you. Unfortunate. Plans? What's next?... Joe

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jmiele
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Re: Edge HD Focal Reducer new [Re: jmiele]
      #4747936 - 08/14/11 04:38 PM

And to your point, you are correct. In the forums, we are either singing praise or winning incessantly.
Joe


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nemo129
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Re: Edge HD Focal Reducer new [Re: jmiele]
      #4748003 - 08/14/11 05:20 PM

Joe,
Thanks for asking. Well, for now if I sell the 11", I will invest the cash in a mono CCD camera, filter wheel & filters. It will really help me in my heavily light polluted area as my DSLR is just not cutting it. Don't want to go much off topic here. I do the love the EdgeHD, but I like AP more and with my AT8RC I get some nice pictures. Sure I'd love to have both the new camera and the EdgeHD, but the CFO says no!


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jmiele
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Re: Edge HD Focal Reducer new [Re: nemo129]
      #4748026 - 08/14/11 05:32 PM

Well, your photos are excellent. You will surely be able to take advantage of the benefits of a CCD mono camera and color filters. I submit however, the part of what you do enjoy about the AT8RC, could be satisfied with the Edge 11 had it been able to be reduced to a similar FL.

Joe


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Peter in Reno
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Re: Edge HD Focal Reducer new [Re: jmiele]
      #4748111 - 08/14/11 06:38 PM

Kirk,

Why can't you image at F/10? I have imaged at F/10 with my CPC0800 without difficulties. Today's camera's sensor are sensitive enough to capture great images at high focal ratio like at F/10.

See my images at http://peternagy.smugmug.com . Images at F/10: NGC4565, NGC7331 (30 minute subs!), M51, M106, NGC6946, M16, M20, M27, M57, NGC6905, NGC6781.

I am upgrading CPC0800 with Astro-Physics Mach1GTO GEM (September delivery) and 8" EdgeHD. I plan to image at F/10 as much as I can. I like imaging small DSOs.

Peter


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nemo129
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Re: Edge HD Focal Reducer new [Re: Peter in Reno]
      #4748201 - 08/14/11 07:46 PM

Peter,
I can image at f/10 and have done so. My choice to sell the EdgeHD is an an economic one. For me, to lay out $3k on a camera I will need the funds from that OTA sale. I can also reduce my AT8RC to lower than f/8 which does make life a bit easier. To tell you the truth, the lack of interest in my sale posting on that 'other site' and here, make it seem that I may be keeping my EdgeHD! Economic times, and C's own sale are not making it any easier. I am patient, so I will see what happens. Thanks for the link, your photos are beautiful!


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nemo129
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Re: Edge HD Focal Reducer new [Re: jmiele]
      #4748207 - 08/14/11 07:52 PM

Quote:

Well, your photos are excellent. You will surely be able to take advantage of the benefits of a CCD mono camera and color filters. I submit however, the part of what you do enjoy about the AT8RC, could be satisfied with the Edge 11 had it been able to be reduced to a similar FL.




Joe,
Thank you for the kind words. As you say the mono CCD will benefit me, especially in my red zone, as it will certainly help me overcome the LP! Don't think for a moment I am not mulling over how well that CCD would work in the EdgeHD with or without a FR!
My, we have gone so far off topic!! Sorry guys!


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Peter in Reno
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Re: Edge HD Focal Reducer new [Re: nemo129]
      #4748211 - 08/14/11 07:53 PM

Hi Kirk,

Thanks. I mis-understood your statement earlier about not being able to image at F/10.

Peter


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nemo129
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Re: Edge HD Focal Reducer new [Re: Peter in Reno]
      #4748215 - 08/14/11 07:55 PM

Don't worry Peter its all good!

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Thomas A Davis
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Re: Edge HD Focal Reducer new [Re: Calypte]
      #4748488 - 08/14/11 10:41 PM

Let me make my stand clear on this. I have NO intent of
suing Celestron. As I said, I try to pick my fights in
life, and this one just is not worth picking to me.

As to an AP reducer working on the 9.25" version of the
EdgeHD, I have one, with the proper SCT adapter, and it
fails miserably on it. The 9.25" seems to be the one
scope in the line that works with no reducer commercially
available. I sold mine, bought a 12" ACF that works with
several of my reducers (the Lumicon Giant Easy Guider works
the best), so from that perspective, I am out of this fight.

I do, however, understand the feelings of those that have
bought the scopes with the understanding that a reducer
would be available long before now, and feel that they have
been misled by Celestron.

Tom


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jmiele
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Re: Edge HD Focal Reducer new [Re: Thomas A Davis]
      #4748582 - 08/14/11 11:37 PM

Yeah Tom, so far I've only heard the AP compressor works on the C-14 Edge. Not sure if Sedat tried his on the C-11 yet. Sedat?

As to legal action, I'm no expert but we ain't winning that war. However, I do believe our complaints are heard. Here and elsewhere on the Web. CN has 50,000 member accounts and idk how many lurkers a day. They don't want bad press here and the like. And folks know S&T and Ast Mgz are no place to get objective opinions. Sorry, and I'm sure I'm getting mail on that one. But come on, whens the last time a product got panned in those magz. Never. Here, folks get the down and dirty Fac..Trut... well, strongly worded opinions anyway.

Joe


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nemo129
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Re: Edge HD Focal Reducer new [Re: jmiele]
      #4749190 - 08/15/11 11:27 AM

Joe, you bring up an excellent point! There are a lot of folks here on CN and they are all potential customers. If I was selling a product aimed at a specific segment of those customers (the AP crowd, and let's face it I know visual observers who love having an FR as well) I would not want the general discussion regarding one of my hot products to turn negative. Maybe this thread will put a little nitro in their tank!? If I was a vendor, I would surely pay attention to a large venue like CN. Now we just need to keep our fingers crossed that the message is heard and heeded.

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Re: Edge HD Focal Reducer new [Re: nemo129]
      #4749284 - 08/15/11 12:24 PM

Do not take this as gospel. but my understanding from Celestron is that the design of the focal reducers has proven more difficult than anticipated and their original plan of one reducer for all scopes had to be abandoned. Apparently each EdgeHD aperture needs its own scope-specific reducer, requiring four separate design projects instead of the anticipated single optical formula. Design and testing has been completed on some models, but not all.

To the best of my knowledge, Celestron had every intention of bring out the reducers quickly but, to quote Robert Burns,
"The best-laid schemes o' mice an' men
Gang aft agley,
An' lea'e us nought but grief an' pain . . ."

To the best of my knowledge, Celestron still has every intention of bringing out the reducers as quickly as possible, since the current delay is not in their best interests (as the comments in this thread attest).

However, new products often take more time than anticipated to bring out, for many unexpected reasons, in spite of a manufacturer's best efforts. I speak from experience. Give them the benefit of the doubt.


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Re: Edge HD Focal Reducer new [Re: frebie]
      #4749363 - 08/15/11 01:13 PM

Problem is, I find that completely unacceptable and further testament to their ineptitude. Hows that happen. Many of us have said this for over a year. Now they think it's more complex. Now they think they need one for each scope. The term "gross negligence" comes to mind.

The real capper for me is now that they know this, what do they do? Dig in and fix it? No..... They put those very same "un-compressable" optics into the rest of their line. I have change my position.. I know hope they fail. Oh wait, they already have...

Joe


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Re: Edge HD Focal Reducer new [Re: jmiele]
      #4749435 - 08/15/11 02:05 PM

Joe,

I agree with you on this one. Any good optical designer
will tell you that first, designing a focal reducer to
work with a field flattener is not an easy way to go. It
is far better to make a reducer that combines flattening
properties into the design as a single unit. Once they
built a scope with a built-in flattener, they greatly
increased the task of focal reduction. The Hyoerstar skirts
the issue by not having the flattener as part of the design.
It only makes use of the corrector plate and the primary
mirror.

To design even one model of reducer with a flattener in
the optical train in front of it, is a daunting task. To
produce 4 different models, because of short-sightedness
in the original design makes no sense at all. What were
they thinking, or were they thinking at all when they
released the EdgeHD?

I hope the reducers do get produced, for the sake of those
who bought these scopes, and want to use them at something
other than F/10 or with a Hyperstar.

Tom


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Re: Edge HD Focal Reducer new [Re: Thomas A Davis]
      #4750217 - 08/15/11 09:52 PM

I had emailed them shortly after my C11hd arrived. They told me they had to design a seperate reducer for each model then. That was almost 2 years ago so that is not a new story.

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Re: Edge HD Focal Reducer new [Re: Stew57]
      #4750302 - 08/15/11 10:42 PM

All that tells me is they continued to advertise it while they already knew it wasn't gonna happen. They are Baddies.. Plain and simple. I'm ready to call Arnold Diaz at Channel 7 NY "Shame On You" segment.

Baddies.. Joe


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Re: Edge HD Focal Reducer new [Re: jmiele]
      #4750319 - 08/15/11 10:48 PM

Bad mouthing Celestron is not helping this thread. We get the point. How about helping the OP to find an alternative like Optec or Astro-Physics compressors. Didn't at least one poster posted nice pictures with after market compressors?

Peter


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Re: Edge HD Focal Reducer new [Re: Peter in Reno]
      #4750332 - 08/15/11 10:56 PM

AP only works with the C-14 so far. The Optec leaves you with a horrible 22mm image circle. There's nothing good to say. That's why folks aren't happy.

Joe

Edited by jmiele (08/15/11 11:04 PM)


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Re: Edge HD Focal Reducer new [Re: jmiele]
      #4750386 - 08/15/11 11:33 PM

That's the issue. The Optec seems to work to some degree
on the C11 EdgeHD, and the AP .75X on the C14. I tried
the F/3.3 and F/6.3, both of which did not work, the AP
.75X with the AP SCT adapter, also no good, and the Optec
Lepus at a variety of spacings, with no success, on my
9.25" EdgeHD. The Optec on the C11 seems to be the best
performer, at F/6.2. So the degree of the problem depends
on which EdgeHD you own. Since I owned the 9.25", I had
no options, either Celestron, or aftermarket.

If I had bought the standard SCT version, I could have
bought an 11" for less, and had multiple options for a
reducer. If Celestron had been honest about their
failure to be able to produce a working reducer for the
EdgeHD series, I would have bought a standard C11 instead.
They would still have had my business, and a happy customer.

Tom


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Re: Edge HD Focal Reducer new [Re: Thomas A Davis]
      #4750907 - 08/16/11 09:48 AM

If some dealer were to try every reducer that has been made one might be found that works ok with each scope.
This would take some time as I can recall at least 50 off hand but it might be worth a try.


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Re: Edge HD Focal Reducer new [Re: jmiele]
      #4751018 - 08/16/11 10:50 AM

Quote:

AP only works with the C-14 so far. The Optec leaves you with a horrible 22mm image circle. There's nothing good to say. That's why folks aren't happy.

Joe




What about Nocturnal's images with Optec reducer and QHY8 big color CCD sensor? See post #4736274 (page 11). It seems to fill the whole CCD sensor. It looks great to me. It looks like less vignetting than my regular Celestron focal reducer on CPC0800.

Peter

Edited by Peter in Reno (08/16/11 10:54 AM)


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Re: Edge HD Focal Reducer new [Re: Peter in Reno]
      #4751025 - 08/16/11 10:59 AM

Not discounting the Optec's ability to work. However, at 22mm the image will vignette even the small 8300 chip. The 8300 is NOT a full frame sensor.

That aside, given an 8300 chip and proper flats the vignette can be controlled. However that's not fixing the problem that my Edge with the 50mm image circle (advertised as a photographic instrument) that can't be reduced (a common photographic requirement) and still maintain the original image circle (or close to it).

How nice of Celestron to decide for us what chip we can use with our telescopes. And really Peter, you asked me to stay on point and not point out the negatives with Edge. Perhaps you should stop helping me make my points.
Joe


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Re: Edge HD Focal Reducer new [Re: jmiele]
      #4751045 - 08/16/11 11:09 AM

I am confused. QHY8 is a bigger sensor than 8300 chip and Nocturnal's images are NOT flattened according to his comments. I can barely see any vignetting in his images with Optec's reducer.

According to this web site, 8300 is a full frame sensor.

http://www.qsimaging.com/583-overview.html

Peter

Edited by Peter in Reno (08/16/11 11:14 AM)


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Re: Edge HD Focal Reducer new [Re: Peter in Reno]
      #4751057 - 08/16/11 11:16 AM

Wrong. The 8300 is 18mmx14mm net is a 23mm vignetted field (As the Optec is 22mm). If his chip is bigger and not vignetted, he flatten, cropped or thinks it's not vignetted because he doesn't see it. Get and original FITs and toss it in ccd inspector.

Are you going to do this until you are right because I'm not sure I have that long.
Joe - just trying to get it light.


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Re: Edge HD Focal Reducer new [Re: jmiele]
      #4751063 - 08/16/11 11:19 AM

His camera has a 28.3mm diagonal. What 28-22? 6mm of vignette. He's losing 3mm in each corner.


Joe


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Re: Edge HD Focal Reducer new [Re: jmiele]
      #4751088 - 08/16/11 11:28 AM

I will have to go back home and check my images taken with Celestron focal reducer and regular C-8 but it vignettes quite a bit with my SXVR-M25C (same sensor as QHY8) and may be about the same amount as Optec. I always get a bright circle in the middle and darker edges at the corners. If that's the case, then the vignetting may be normal. Isn't it natural for focal reducer to reduce the window and cause vignetting? Do you know Celestron focal reducer spec for image circle?

I am not trying to prove anybody wrong. I was simply gathering the facts and the facts I have gathered sometimes says the opposite of what you have been saying. Are you saying that QSI is wrong to say that 8300 is a full frame sensor? QSI is not the only camera company to say that.

Peter


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Re: Edge HD Focal Reducer new [Re: Peter in Reno]
      #4751095 - 08/16/11 11:33 AM

Quote:

According to this web site, 8300 is a full frame sensor.




It is. Full frame refers to the technology of the chip. The ST-7 has quite a small chip - but it's full frame.

Some DSLR vendors are using the term "full frame" rather than the designation they really mean, which is "full size", to refer to cameras with a 35mm diagonal chip rather than a reduced, APS-sized chip That distinction isn't relevant in CCD cameras because there's no such thing as a "full size" chip - the chip in a CCD camera can be whatever size is selected (and some are larger than 35mm diagonal).


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Re: Edge HD Focal Reducer new [Re: Peter in Reno]
      #4751098 - 08/16/11 11:34 AM

Kodak spec: http://www.kodak.com/ek/US/en/KODAK_Image_Sensor_Solutions_-_KAF-8300.htm

It also says full frame.

Peter


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Re: Edge HD Focal Reducer new [Re: Peter in Reno]
      #4751102 - 08/16/11 11:36 AM

I know Peter we're just playing. Your points are well taken. TBH, that small a vignette is something folks could probably live with by using flats if they have the 8300 chip. In that case they could use the Optec. The problem is, many use full frame SLR's now and it's killing them.

As for the standard old F6.3? I looked for that once and couldn't find it. I thought it was on the order of 35mm. That would make it similar to the Starizona one I have. It works on the Standards and leave a 35mm image circle. Which BTW, also is a bit vignetted.

Joe


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Re: Edge HD Focal Reducer new [Re: Peter in Reno]
      #4751105 - 08/16/11 11:37 AM

Quote:

Isn't it natural for focal reducer to reduce the window and cause vignetting?




It's normal for a simple reducer to cause uneven illumination (one form of vignetting). If too small, it can also cause light cutoff at the edges (another form of vignetting).


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Re: Edge HD Focal Reducer new [Re: jmiele]
      #4751111 - 08/16/11 11:40 AM

As soon as I go home for lunch, I will upload my sample sub taken with C-8 and focal reducer for you and others to evaluate and compare to others used with Optec focal reducer. Do you have software to read FIT files? Or shall I upload TIF files? It will be a single sub and unprocessed. I used the proper 105 or 106mm focal reducer spacing.

Peter


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Re: Edge HD Focal Reducer new [Re: jmiele]
      #4751126 - 08/16/11 11:47 AM

Quote:

Wrong. The 8300 is 18mmx14mm net is a 23mm vignetted field (As the Optec is 22mm). If his chip is bigger and not vignetted, he flatten, cropped or thinks it's not vignetted because he doesn't see it. Get and original FITs and toss it in ccd inspector.

Are you going to do this until you are right because I'm not sure I have that long.
Joe - just trying to get it light.




Hey! I do know what I'm doing and I don't lie. I resent that you're implying that I'm either incompetent or a liar. I said I did not flatten and did not crop. Enough already.

I posted the astrometry.net link so you can see the exact image scale and image properties. You can then see that there is no significant crop.

Here is the post I made:

http://www.cloudynights.com/ubbthreads/showthreaded.php/Cat/0/Number/4736274/page/0/view/collapsed/sb/5/o/all/vc/1

"Just stacked, not flattened so you can see vignetting". Note I did not say 'no vignetting'. Even a casual glance at the image shows the center is brighter, as expected of ANY optical system. If you had gone through the trouble of downloading the full sized image you would have seen the size is 2,958px × 1,962px which is very close to the entire QHY8 sensor size. NO CROPPING.

Djeez, you try to supply some impartial data and even that gets twisted to suit a point. Discuss the star quality all you want. I've already posted my opinion.

I'm unsubscribing from this thread. It's pointless.

Edited by Nocturnal (08/16/11 11:48 AM)


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Re: Edge HD Focal Reducer new [Re: Nocturnal]
      #4751156 - 08/16/11 12:05 PM

I said nothing of the sort. I'm sorry you feel that way. Given the math, if you look at your photo under ccd inspector you will see vignetting. It's as simple as 2+2 =4. You cannot illuminate a 28mm Diaginal chip in a 22mm image circle, sorry.

As you are unsubscribing from the thread it's unfortunate your not reading this. You posted your opinion base on your observations, mine are base on the math. I'm sorry we don't agree.

Joe


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Re: Edge HD Focal Reducer new [Re: jmiele]
      #4751162 - 08/16/11 12:09 PM

BTW, the vignette is apparent without CCD Inspector in those photos. As to you not saying "no vignette", I was working with the data a had. Peter stated you had no vignette. I did not look at your posting until now.

Joe


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Re: Edge HD Focal Reducer new [Re: jmiele]
      #4751183 - 08/16/11 12:20 PM

This is a very long thread and no one wants to read the whole thang the first time or go back and search for data.

Anyway, the EdgeHD is a new concept and can seem to fool Optec's spec of 22mm window. If Nocturnal's emperical data proves the Optec's window may be bigger, then that's good news. I favor emperical data over theoretical. Optec may not have all sizes of EdgeHD to test or have consecutive nights of testing. They need to thoroughly test every thing before advertising their spec. I don't want to be a guienna pig to test their products. I want to image and get great results the first time.

Peter


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Re: Edge HD Focal Reducer new [Re: Peter in Reno]
      #4751206 - 08/16/11 12:30 PM

Fair enough Peter. I concede to that point. I also sent a PM to Nocturnal as it was not my intent to upset anyone. The work he has done is certainly interesting and I should have fully review it before posting a response. His efforts are to be commended.

And Peter, I know you just what things to work out and have the best of intentions. I on the other hand, seem to be a trouble maker. I never intend for that to be the case however. Joe


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Re: Edge HD Focal Reducer new [Re: jmiele]
      #4751276 - 08/16/11 01:03 PM

Let's not get too far afield from the actual issue, though.
The Optec unit works with one model, the 11" EdgeHD, and
it works well enough that it can be said if you have an
11", you're fairly well covered.

The problem of the other models still exists. Asking a
buyer to try 50 focal reducers in an effort to find one
that works (I tried 4 reducers on my 9.25" with no success),
is really asking too much. Even for a dealer to do so. It
really does fall back on Celestron to do this, and so far,
they have dropped the ball.

It needs to be stated again. All EdgeHD models need a
reducer, not just the C11. We can take the 11" version
out of the picture, but thank Optec for that one. Celestron
still needs to fix this.

Tom


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Re: Edge HD Focal Reducer new [Re: Thomas A Davis]
      #4751490 - 08/16/11 02:44 PM Attachment (21 downloads)

Here is a sample 10 minute sub of NGC253 taken with CPC0800 and Celestron F/6.3 focal reducer with proper spacing of 105mm and SXVR-M25C color CCD camera.

BMP image (stretched and unprocessed): http://www.sendspace.com/file/fggnte

FIT image (unstretched and unprocessed): http://www.sendspace.com/file/sm2aq4

Warning. BMP image is 17MB and FIT image is 11MB.

Note: The shadow at the bottom is the OAG's prism partially blocking the CCD sensor.

EDIT: You need to click on "Click here to start download from sendspace", not the "DOWNLOAD" button.

You can see the final processed of NGC253 at: http://peternagy.smugmug.com/

Peter

Edited by Peter in Reno (08/16/11 03:21 PM)


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Re: Edge HD Focal Reducer new [Re: Peter in Reno]
      #4751629 - 08/16/11 04:10 PM

Peter,

Any of the scopes using the F/6.3 reducer will vignette.
I didn't raise the issue, but the problem is the use of
the smaller SCT thread to attach the reducer, and on the
8" version (the one you used here), that is the only
method of attaching a reducer. The smaller opening that
is created by the adapter will vignette on larger chips.

If you have a reducer on either the 9.25", 11", or 14"
versions of the EdgeHD, and make use of the large adapter
ring to attach the reducer, vignetting is less of an issue,
due to the larger opening.

Tom


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Re: Edge HD Focal Reducer *DELETED* new [Re: Peter in Reno]
      #4751630 - 08/16/11 04:10 PM

Post deleted by Thomas A Davis

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Re: Edge HD Focal Reducer new [Re: Thomas A Davis]
      #4751643 - 08/16/11 04:16 PM

My point was to show how much the standard Celestron SCT and focal reducer vignettes to compare to Optec focal reducer. I don't have the tools to measure the window especially in "mm" as opposed to pixels or arc-seconds.

There was a big debate going on about how tiny Optec focal reducer window is. So I wanted to post this picture for others to analyze and compare to see if Optec focal reducer is worth it for EdgeHD scopes.

Peter


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Re: Edge HD Focal Reducer new [Re: Peter in Reno]
      #4751681 - 08/16/11 04:37 PM

The bottleneck on the C8 is the rear opening on the SCT
rear thread. This will cause vignetting with any reducer.
Any reducer making use of the larger 3" adapter on the 9.25"
and larger EdgeHDs will have an advantage. due to the larger
opening. The Optec Lepus reducer attaches to the larger
adapter thread on the larger models of the EdgeHD. That
alone will reduce vignetting with the reducer, using the
3.25" thread versus the 2" thread on the 8" version.

Tom


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Re: Edge HD Focal Reducer new [Re: Thomas A Davis]
      #4751841 - 08/16/11 06:20 PM

That is correct Tom. However with the Edge even using the 3.25" doesn't help as the baffle tube is so small. That too, is part of the Edge issue(s). It works fine at the intrinsic FL, but is rather undersized when it comes to compression. Joe

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Re: Edge HD Focal Reducer new [Re: Peter in Reno]
      #4751894 - 08/16/11 06:50 PM

Quote:

...Celestron F/6.3 focal reducer with proper spacing of 105mm



Peter, how did you determine "proper spacing?" I'm not arguing the point. Just asking for your experience. I have a Meade 10-inch (ca. 2001) & Meade reducer, which I think is identical to the Celestron, and I have used a spacing of about 105 mm. I have websites and an S&T article that give this figure. But some people insist on something about 87 mm, and I know a guy who's done some fine things with a C8 & Celestron reducer, and he's using 87 mm or thereabouts. I've never liked the results with the aforementioned Meade & reducer, so I do my imaging with other scopes.

As to the subject of the thread. I've looked at & thought about buying one of the EdgeHD scopes, and I even know one of the beta testers (he used the 8-inch at f/10). But I'm too old to put up with any more astronomical vaporware. Stuff gets announced, and it's often years before you can actually buy one. I think they like to test the level of interest & potential sales before actually proceeding with proposed gear. A principal with one of the CCD manufacturers denied to me that his company does that, and maybe he's right, although his company's history suggests otherwise. In any case -- no EdgeHD for me until they have reducers on the shelves!


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Re: Edge HD Focal Reducer new [Re: Thomas A Davis]
      #4751912 - 08/16/11 06:59 PM

Quote:

The bottleneck on the C8 is the rear opening on the SCT
rear thread. This will cause vignetting with any reducer.
Any reducer making use of the larger 3" adapter on the 9.25"
and larger EdgeHDs will have an advantage. due to the larger
opening. The Optec Lepus reducer attaches to the larger
adapter thread on the larger models of the EdgeHD. That
alone will reduce vignetting with the reducer, using the
3.25" thread versus the 2" thread on the 8" version.

Tom




And yet the vignetting on a C8 is _very_ minimal to the point of "unnoticeable," and this is from someone who shot many, many a roll of 35mm film with an r/c equipped C8.


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Re: Edge HD Focal Reducer new [Re: Calypte]
      #4751915 - 08/16/11 07:00 PM

From Celestron's web site:

http://www.celestron.com/c3/support3/index.php?_m=knowledgebase&_a=viewarticle&nav=0&kbarticleid=2243

I use a wooden ruler and measure from the rear of focal reducer to the end of T-Thread connector and then add 18mm back focus of my camera CCD sensor.

Peter


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Re: Edge HD Focal Reducer new [Re: rmollise]
      #4752309 - 08/16/11 11:12 PM

Quote:

And yet the vignetting on a C8 is _very_ minimal to the point of "unnoticeable," and this is from someone who shot many, many a roll of 35mm film with an r/c equipped C8




With film I would tend to agree. I found film to be much
more forgiving in terms of vignetting. CCD chips are much
more sensitive, and tend show a few percent of vignetting
readily in an image. Peter's image he posted with the C8
and F/6.3 reducer could have been readly fixed with a flat
field frame, so the amount of vignetting was not a real
issue. It did show vignetting, though.

My point had been that the large SCT adapter vignettes less,
so the Optec unit installed in that manner could well have
less of an issue. Both reducers have a small enough issue
that a flat will easily fix.

Tom


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Peter in Reno
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Re: Edge HD Focal Reducer new [Re: Thomas A Davis]
      #4752356 - 08/16/11 11:35 PM

When I was a teenager, I had an orange tube C-8 and imaged with film, 35mm SLR camera and focal reducer. I remember vividly that it vignetted quite a bit on Kodak 103aF B&W negatives and I don't think it was as forgiving as with CCD cameras. I always see a bright circle right in the middle surrounded by dark corners and was worse than my current SXVR-M25C CCD camera.

I am not sure what you mean by more forgiving. Are you saying using focal reducer and 35mm film, it vignettes a lot less than CCD cameras?

Peter


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Peter in Reno
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Re: Edge HD Focal Reducer new [Re: Peter in Reno]
      #4752379 - 08/16/11 11:52 PM

35 years ago is pretty hard to remember certain things. It was called "tele-compressor" instead of focal reducer. It may have been a factor to cause significant vignetting, I don't know. I was using Celestron Off Axis Guider and Canon F1 SLR camera. There was no specification about proper spacing back then as far as I can remember. So, it may be an unfair comparison to today's focal reducers and CCD cameras.

Peter


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Thomas A Davis
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Re: Edge HD Focal Reducer new [Re: Peter in Reno]
      #4752951 - 08/17/11 11:20 AM

Peter,

No, it actually will vignette more, due to the larger
format. If you processed your own, and there was enough
light pollution where you photographed from, yes, you
would definitely see a vignetting issue. I used color film
with my SCTs back in the 80s, and had a local camera shop
process. They always printed to a dark background (and the
skies were much darker then).

With digital, we process ourselves, and vignetting is more
of an issue, since we are trying to bring out the fainter
details. In the process, vignetting is an problem. If you
were trying to pull out faint details from film, yes, you
would indeed have a problem, and flats were not an option
with film.

Keep in mind, though, getting back to my point, vignetting
is created by ANY bottleneck in the optical train. How the
camera is attached to the reducer is a key issue as well.
Some of the old setups would use a 1 1/4" adapter to an
SCT screw on adapter. That alone will create significant
vignetting. I tried to use a 2" adapter once they were
available, and that helped reduce vignetting to manageable
level.

Using the right adapter with a large adapter ring on an
SCT will make the bottleneck the reducer itself (or in the
case of the EdgeHD, the opening on the field flattener).

Flats are just part of imaging, not just with SCTs, but
with other designs as well.

Tom