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Equipment Discussions >> Electronically Assisted Astronomy

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mattflastro
Vendor - Astrovideo Systems


Reged: 07/31/09

Loc: Brevard County , FL
Focal Reducer for Video SCT SCopes down to F/1.5
      #5752848 - 03/23/13 10:09 PM Attachment (121 downloads)

Hyperstar is an option that gets down to F/2 .
Meade .33x gets down to F/3.3 .
I am not aware of any other options that could be used , which should not involve disassembling the corrector and buying $1000 worth of mechanical+optical parts .
The image below is shot with my home made reducer and my Meade 10 inch F/10 SCT .
The result is F/1.55 apparently (I might be off by a little, actual range based on transit time is 1.5 to 1.6 ) .
Is there anything like this available commercially ?
Please note that my reducer can NOT work with cameras that have a CCD any larger than 1/3" ( 6mm diagonal).


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mclewis1
Thread Killer
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Reged: 02/25/06

Loc: New Brunswick, Canada
Re: Focal Reducer for Video SCT SCopes down to F/1.5 new [Re: mattflastro]
      #5752916 - 03/23/13 10:52 PM

I don't know of any add on commercial product that's specifically intended to be used below .3x. It's tough to maintain image quality at those levels of reduction and there's also very severe vignetting outside of a small image circle.

The Mallincam MFR-5 if "abused" with spacers both between the lens elements and behind it (between it and the sensor) can get you down below .3x but the image quality isn't great outside an area about the size of a 1/3" sensor.

I can also get down to around .25x with my SCTs by stacking the SCT f6.3 reducer and a .5x reducer, but again poor image quality at the edges of a 1/2" sensor.

Stacking focal reducers is a viable solution particularly if you relax the spacing a bit (don't push them to their limits) and aren't looking for high quality wide fields that cover larger sensors.

Getting down under .2x is quite impressive, can you show us how you did it? A shot of a star field will tell you more about the image quality (it's really tough to keep stars small and tight right across a fov). Also how about a shot at a longer exposure on a 1/2" sensor so we can see the vignetting?


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highfnum
Carpal Tunnel
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Reged: 09/06/06

Loc: NE USA
Re: Focal Reducer for Video SCT SCopes down to F/1.5 new [Re: mclewis1]
      #5753268 - 03/24/13 04:47 AM

What you did is tuff
I do have sc5 and sc8 @ 1.6 1.5 those are special cameras


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Moromete
professor emeritus


Reged: 02/15/12

Loc: Romania
Re: Focal Reducer for Video SCT SCopes down to F/1.5 new [Re: mattflastro]
      #5754322 - 03/24/13 03:46 PM

Excelent stuff. Bravo!

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ippiu
member


Reged: 12/06/10

Loc: Italy
Re: Focal Reducer for Video SCT SCopes down to F/1.5 new [Re: mattflastro]
      #5754546 - 03/24/13 05:35 PM

Quote:


Is there anything like this available commercially ?
Please note that my reducer can NOT work with cameras that have a CCD any larger than 1/3" ( 6mm diagonal).




Yes! There is...
A normal focal reducer like this: http://www.teleskop-express.de/shop/product_info.php/info/p365_TS-Focal-reduc...

with 74 mm extension tubes spacing. I have a watec 120 n+, that is 1/2" sensor size.

Total factor reduction: f1.75, more or less. With huge coma at the borders, obviously


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GlennLeDrew
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Reged: 06/18/08

Loc: Ottawa, Ontario, Canada
Re: Focal Reducer for Video SCT SCopes down to F/1.5 new [Re: ippiu]
      #5754683 - 03/24/13 06:29 PM

It's necessary to check that aperture reduction is not occurring. To obtain such aggressive reductions, the reducer optics must themselves be 'fast', else the on-axis light cone (to say nothing of off-axis light cones) will not be fully accommodated. One can get significant reductions in image scale with large reducer-to-focus spacings, but if the reducer's clear aperture is not taking in the full light cone the working f/ratio will be longer than assumed. In other words, image brightness is less.

There are easy ways to check if aperture reduction is happening...

I'd love to see what you've cobbled up!


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mpgxsvcd
Carpal Tunnel


Reged: 12/21/11

Loc: Raleigh, North Carolina
Re: Focal Reducer for Video SCT SCopes down to F/1.5 new [Re: GlennLeDrew]
      #5755978 - 03/25/13 11:34 AM

Here is the fastest telephoto lens I could find. It was made for medium format so it will probably work even with larger sensors.

Imagine this thing on a large crop factor camera like the Nikon 1 series.

240mm f/1.2 with an image circle that covers 6x7 medium format

http://photography-on-the.net/forum/showthread.php?t=872418

Edited by mpgxsvcd (03/25/13 11:35 AM)


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nytecam
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Reged: 08/20/05

Loc: London UK
Re: Focal Reducer for Video SCT SCopes down to F/1.5 new [Re: mattflastro]
      #5757530 - 03/26/13 05:58 AM

Quote:

Hyperstar is an option that gets down to F/2 .
Meade .33x gets down to F/3.3 .....The image below is shot with my home made reducer and my Meade 10 inch F/10 SCT .
The result is F/1.55 apparently ....


What Glenn says is spot-on I've my FR daylight tests somewhere on distant chimney pots - why waste precious night skies! Whilst it's possible to stack FRs like my Meade 3.3, 6.3 and my DIY 7.0 FRs, in decending order of power, 'speeds' faster than the fastest f/3.3 optic is improbable.

Whilst scaling the image, compared to the native f/10, it seems possible to reach f/1.5 but this is done by severely vignetting the scope's full aperture - the actual 'speed' remains ~f/3.3. Good try but there ain't no gain without pain I've optomised my 12" SCT to run a f/3.6 via the Meade f/3.3 FR and a near perfect balance for my Lodestar camera in speed and coverage on DSOs


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GlennLeDrew
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Reged: 06/18/08

Loc: Ottawa, Ontario, Canada
Re: Focal Reducer for Video SCT SCopes down to F/1.5 new [Re: nytecam]
      #5758745 - 03/26/13 05:43 PM

My own tests indicate that for f/10 systems using various 'off-the-shelf' reducers and combinations yields a limit near f/2.8 before aperture reduction has reared its head, but the poor image quality (on-axis spherical aberration, to say nothing of the worse off-axis coma and field curvature) are becoming intolerable.

A multi-element reducer of rather fast aperture ratio of about f/2, if not faster), and perhaps/probably aspherized, would be required in order to get to the f/1.5 level at the focus. And of course the inherent field illumination must support the significant reduction of nearly 7X (from f/10); a 40mm image circle is shrunk to 6mm.

Hmmm... I wonder what a fast camera lens could do. Something like my 50mm f/1.7 Minolta. I can see some experimenting in the near future...

Again, Matt, I'd love to see what you've made!


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nytecam
Postmaster


Reged: 08/20/05

Loc: London UK
Re: Focal Reducer for Video SCT SCopes down to F/1.5 new [Re: GlennLeDrew]
      #5759566 - 03/27/13 04:23 AM

Quote:

Hmmm... I wonder what a fast camera lens could do. Something like my 50mm f/1.7 Minolta. I can see some experimenting in the near future...


I've used a variety of fast short fl lenses on my e-finder that also doubles as a widefield astrograph with longer exposures. My favourite lens is a 85mm f/2 Jupiter lens + red filter. The filter seems to supress my LP and act as a poorman's H-alpha filter. Checkout my e-finder page [down page] and sample pics N America Neb - M31 and below



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GlennLeDrew
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Reged: 06/18/08

Loc: Ottawa, Ontario, Canada
Re: Focal Reducer for Video SCT SCopes down to F/1.5 new [Re: nytecam]
      #5759575 - 03/27/13 04:48 AM

Maurice,
I meant a fast camera lens used as a focal reducer in a long f.l. system, not by itself (which we know works quite well.)

Matt's absence after his initial teaser is keenly felt. Hint, hint, Matt!


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nytecam
Postmaster


Reged: 08/20/05

Loc: London UK
Re: Focal Reducer for Video SCT SCopes down to F/1.5 new [Re: GlennLeDrew]
      #5759604 - 03/27/13 05:42 AM

Quote:

Maurice, I meant a fast camera lens used as a focal reducer in a long f.l. system, not by itself (which we know works quite well.)


Glenn - you are normally pedantically precise but fell on that one I don't think FRs will improve on ~f2.8 or less bearing in mind the horrid aberrations they incur. f/2 Hyperstar seems the proven if expensive answer but then too much 'speed' can be a disadvantage as we're all aware under commonplace LP

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GlennLeDrew
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Reged: 06/18/08

Loc: Ottawa, Ontario, Canada
Re: Focal Reducer for Video SCT SCopes down to F/1.5 new [Re: nytecam]
      #5759638 - 03/27/13 06:58 AM

Indeed, Maurice, my pedantic precision fall by the wayside.

For the benefit of all, it must be stressed that the roughly f/2.8 limit via focal reduction applies to longer systems in the range of f/10.

I use a dual lens reducer--the Mallincam MFR-5--on an f/5 refractor to achieve f/2.5, delivering full aperture performance.

I provide this example merely to illustrate that the final, effective f/ratio depends also on the objective's f/ratio.

Incidentally, the Hyperstar system is not at all a focally-reduced configuration, for the objective f/ratio is already at or near to f/2 (depending on the specific scope.) The Hyperstar optics merely correct the off-axis aberrations and field curvature, retaining the system speed provided by the fast objective.


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mattflastro
Vendor - Astrovideo Systems


Reged: 07/31/09

Loc: Brevard County , FL
Re: Focal Reducer for Video SCT SCopes down to F/1.5 new [Re: GlennLeDrew]
      #5763596 - 03/29/13 03:38 AM Attachment (58 downloads)

Quote:

Maurice,
I meant a fast camera lens used as a focal reducer in a long f.l. system, not by itself (which we know works quite well.)

Matt's absence after his initial teaser is keenly felt. Hint, hint, Matt!



Sorry for the delay. The Moon pic I posted at the beginning of this thread was taken with my home made reducer and a Meade 10" F/10 SCT, working at around F1.5 with no vignetting .
Since posting that image I was busy making another reducer to work with my Meade 8" F10 SCT , which has a smaller baffle tube and is a much more portable scope .
Of course as soon as I finished assembling the parts and setting up , thin clouds covered most of the sky.
Here's a pic taken with the Meade 8" at F2 . Please ignore the skyglow due to being shot thru the (thin) clouds . Also didn't have time for focusing properly so it's just eyeballed . Both images are unprocessed frames from my live video feed , taken with a cheap digital DVR .


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mattflastro
Vendor - Astrovideo Systems


Reged: 07/31/09

Loc: Brevard County , FL
Re: Focal Reducer for Video SCT SCopes down to F/1.5 new [Re: mattflastro]
      #5763605 - 03/29/13 03:49 AM

Just to clarify, both the F1.5 reducer for the 10" F10 SCT and the F2 reducer for the 8" F10 SCT are working without vignetting with 1/3" ccd's .
The reducers attach to the back of the scope , not in front Fastar/Hyperstar style.
Even with this reduction, the cameras have a field of view that's still narrower than the scopes , so there's still some margin , although not much .


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nytecam
Postmaster


Reged: 08/20/05

Loc: London UK
Re: Focal Reducer for Video SCT SCopes down to F/1.5 new [Re: mattflastro]
      #5763754 - 03/29/13 07:28 AM

Sorry to doubt your DIY unvignetted FRs - practise trumps theory - BTW checked your M42 starfield for 5.3x3.8mm chip =6mm diagonal = f/1.75 eg faster than f/2

My own experiments I found the secondary caused vignetting at fast FRs by dimming the image


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GlennLeDrew
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Reged: 06/18/08

Loc: Ottawa, Ontario, Canada
Re: Focal Reducer for Video SCT SCopes down to F/1.5 new [Re: nytecam]
      #5765551 - 03/29/13 07:07 PM

Matt,
Have you verified that you're indeed working at or at least near to full aperture? Enquiring minds want to know!

An image by itself will not tell you this.


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GlennLeDrew
Postmaster
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Reged: 06/18/08

Loc: Ottawa, Ontario, Canada
Re: Focal Reducer for Video SCT SCopes down to F/1.5 new [Re: GlennLeDrew]
      #5766029 - 03/30/13 01:25 AM

I tried a 50mm f/1.7 camera lens on an 80mm f/5 achromat. The spherical aberration was notable, enough to quash that notion. I merely held the camera behind the lens, and so could not measure the reduction factor from the shaky image during the quick test. From the image scale, I'd guess a reduction factor of about 0.3X. The lens was certainly at its limit for the acceptance of the light cone, if not very slightly clipping the aperture.

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mattflastro
Vendor - Astrovideo Systems


Reged: 07/31/09

Loc: Brevard County , FL
Re: Focal Reducer for Video SCT SCopes down to F/1.5 new [Re: GlennLeDrew]
      #5767058 - 03/30/13 03:26 PM

Quote:

Matt,
Have you verified that you're indeed working at or at least near to full aperture? Enquiring minds want to know!

An image by itself will not tell you this.



A reduction from a 40mm image circle to a 6mm image circle is theoretically possible, I hope you agree. That would be a reduction factor of 6.66 . A reduction factor of only 6 down to a 6mm image circle would need to start from a 36mm image circle, same as a full frame sensor or film . F10 SCT's are capable of larger than 35mm image circle.
Simply because people haven't built such reducers doesn't mean it is impossible, it's not even pushing the limit .


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GlennLeDrew
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Reged: 06/18/08

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Re: Focal Reducer for Video SCT SCopes down to F/1.5 new [Re: mattflastro]
      #5767143 - 03/30/13 04:44 PM

Indeed. Now, obtaining the reduced image scale is one thing. But doing this while preserving full aperture performance is another. You can check for this with everything assembled and focused at infinity. Aim the scope toward the daytime sky, or while indoors shine a light down the front end, so that you can see the detector. Move your gaze toward the outer edge of the corrector, noting the point at which the *center* of the CCD becomes clipped by some obstructor. If you can see the chip's center until it it reaches the edge of the primary mirror, you're working at full aperture.

It's virtually certain that the chip's corners will be clipped well before your sight line reaches the edge of the objective. This means you'll have to estimate the location of the chip's center, which is facilitated by quickly moving your eye back nearer to the center (looking just past the edge of the secondary.)


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GlennLeDrew
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Reged: 06/18/08

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Re: Focal Reducer for Video SCT SCopes down to F/1.5 new [Re: GlennLeDrew]
      #5772157 - 04/02/13 04:39 AM

In reviewing the M42 image, I'm struck by the lack of field curvature and coma. The 0.33X reducers *designed specially* for SCTs so as to correct these two aberrations are probably at just about the limit of what's possible for a 3-lens unit.

That a cobbled up, home made rig can provide 0.15-0.2X reductions with such evenness of illumination and lack of off-axis aberrations is astonishing. To the point that I'm really beginning to doubt the whole thing.

Any further details to quell my misgivings?


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GlennLeDrew
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Re: Focal Reducer for Video SCT SCopes down to F/1.5 new [Re: GlennLeDrew]
      #5774312 - 04/02/13 10:19 PM

To further build upon the thinking inspiring my doubts...

Small-chip cameras have been around since the first CCD cameras. And Meade designed a suitable reducer for those small formats, it being the f/3.3 unit for f/10 SCTs. An even faster device would have been something of a Holy Grail, but seems to not have been easily achievable. And so the jump to 'extreme' speed was realized by the front-end corrector, whose current and most popular incarnation is Starizona's Hyperstar.

Now comes along a hobbyist claiming to achieve a focal reducer of simply astonishing capability not heretofore seen. A reduction factor of 0.15X which delivers good correction and little vignetting. This is a *very great* amount of wavefront shaping; no mean feat to achieve. And we're given to understand (by reading between the lines) that such had been obtained at no great expense and with existing lenses.

It might pose a difficult problem for an optical designer to come up with such a device, it requiring computation and numerous elements to deliver such performance. The chance of matching up a couple or few off-the-shelf lenses or existing reducers is not expected by chance to come close.

And if the 0.15X worked well for the 10" SCT, why bother to make up a different (0.2X, or so was thought) version for the 8" SCT when the already proven 0.15X should work as well on the 8"?

In the end, the numbers just seem to be *too* good, based on what has been achieved prior, and having some understanding of what it takes to perform such optical tasks.

A number of questions are wanting answering.


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budman1961
Pooh-Bah
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Reged: 02/25/11

Loc: Springfield, MO
Re: Focal Reducer for Video SCT SCopes down to F/1.5 new [Re: GlennLeDrew]
      #5774465 - 04/02/13 11:47 PM

This was just another threadstarter with no finish thread.........

Too bad!

andy


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mattflastro
Vendor - Astrovideo Systems


Reged: 07/31/09

Loc: Brevard County , FL
Re: Focal Reducer for Video SCT SCopes down to F/1.5 new [Re: GlennLeDrew]
      #5774951 - 04/03/13 09:10 AM

Quote:

To further build upon the thinking inspiring my doubts...

Small-chip cameras have been around since the first CCD cameras. And Meade designed a suitable reducer for those small formats, it being the f/3.3 unit for f/10 SCTs. An even faster device would have been something of a Holy Grail, but seems to not have been easily achievable. And so the jump to 'extreme' speed was realized by the front-end corrector, whose current and most popular incarnation is Starizona's Hyperstar.

Now comes along a hobbyist claiming to achieve a focal reducer of simply astonishing capability not heretofore seen. A reduction factor of 0.15X which delivers good correction and little vignetting. This is a *very great* amount of wavefront shaping; no mean feat to achieve. And we're given to understand (by reading between the lines) that such had been obtained at no great expense and with existing lenses.

It might pose a difficult problem for an optical designer to come up with such a device, it requiring computation and numerous elements to deliver such performance. The chance of matching up a couple or few off-the-shelf lenses or existing reducers is not expected by chance to come close.

And if the 0.15X worked well for the 10" SCT, why bother to make up a different (0.2X, or so was thought) version for the 8" SCT when the already proven 0.15X should work as well on the 8"?

In the end, the numbers just seem to be *too* good, based on what has been achieved prior, and having some understanding of what it takes to perform such optical tasks.

A number of questions are wanting answering.



Glenn, thanks for pointing out the value of such a reducer. At this point it is not consistent wiht my goals to place such a reducer desgn in the public domain.


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budman1961
Pooh-Bah
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Reged: 02/25/11

Loc: Springfield, MO
Re: Focal Reducer for Video SCT SCopes down to F/1.5 new [Re: mattflastro]
      #5775293 - 04/03/13 11:14 AM

He's tell us, but he's have to kill us.......lol

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Dwight J
scholastic sledgehammer
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Reged: 05/14/09

Loc: Lethbridge, Alberta, Canada
Re: Focal Reducer for Video SCT SCopes down to F/1.5 new [Re: budman1961]
      #5775516 - 04/03/13 12:59 PM



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GlennLeDrew
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Reged: 06/18/08

Loc: Ottawa, Ontario, Canada
Re: Focal Reducer for Video SCT SCopes down to F/1.5 new [Re: Dwight J]
      #5775601 - 04/03/13 01:39 PM

When might we look forward to purchasing one, then?

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budman1961
Pooh-Bah
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Reged: 02/25/11

Loc: Springfield, MO
Re: Focal Reducer for Video SCT SCopes down to F/1.5 new [Re: GlennLeDrew]
      #5775697 - 04/03/13 02:23 PM

Vaporware

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Devon
member


Reged: 03/06/10

Loc: OK
Re: Focal Reducer for Video SCT SCopes down to F/1.5 new [Re: budman1961]
      #5775855 - 04/03/13 03:48 PM

Is BSware a term...?

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Chris A
Pooh-Bah


Reged: 02/03/07

Loc: Toronto, Canada
Re: Focal Reducer for Video SCT SCopes down to F/1.5 new [Re: GlennLeDrew]
      #5775883 - 04/03/13 04:04 PM

Glenn, Andy, Dwight and Devon. This is known (M42 Image Matt posted)as Photoshop tricks and I could have easily fixed the stars right out to the very edge and remove the vignetting LOL. This is why I do not like to judge a camera from posted images and prefer see live with my own eyes a broadcast on NSN!!

Chris A
Astrogate


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GlennLeDrew
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Reged: 06/18/08

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Re: Focal Reducer for Video SCT SCopes down to F/1.5 new [Re: Chris A]
      #5776132 - 04/03/13 06:23 PM

Chris,
If embellishment, adornment or even fakery is intended, then it's a *lot* simpler to substitute an image taken with even a rather different rig but which has the image scale of the intended 'simulated' view...

Matt,
If you wish not to have such speculation continue, then at least let us know if you're indeed developing (or helping to develop) something which eventually will be available commercially. To drop a 'teaser' and then clam up with the "not for the public domain" brush-off is not consistent with a 'Skunk Works' project for which you have not oversight or signing authority. And so it stands to reason that you're the one answerable, and can only do yourself a favor by providing even a smidgen of supportable clarification.

And what about the state of the camera you also 'teased' us with a little while back? Is it to be considered in the same category?


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budman1961
Pooh-Bah
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Reged: 02/25/11

Loc: Springfield, MO
Re: Focal Reducer for Video SCT SCopes down to F/1.5 new [Re: GlennLeDrew]
      #5776303 - 04/03/13 07:51 PM

Both the FR and camera are made of a rare-earth material.....Unobtanium!

lol

Andy


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jimthompson
member


Reged: 10/06/09

Loc: Ottawa, Canada
Re: Focal Reducer for Video SCT SCopes down to F/1.5 new [Re: GlennLeDrew]
      #5776502 - 04/03/13 09:13 PM

You are my hero of the day Glenn.

While we're all gathered here today, I wonder Glenn if you can help me to understand something that I'm unclear on regarding focal reduction or extension. How does the distance from the primary to focus plane change with reduction or extension ratio? I'm guessing that will depend on the relative position of the reducer/telextender in the light cone. Is it correct to assume that the light cone between reducer/telextender and camera will be the same solid angle as a cone subtended by the primary's aperture with height equal to the effective focal length? Or is the cone angle of light exiting the reducer/extender fixed by that element's focal length and only the length/diameter varies? Any insight you can provide would be appreciated.

Best Regards,

Jim Thompson
AbbeyRoadObservatory


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ccs_hello
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Reged: 07/03/04

Re: Focal Reducer for Video SCT SCopes down to F/1.5 new [Re: budman1961]
      #5776612 - 04/03/13 10:09 PM Attachment (18 downloads)

For 0.2x:
Not completely impossible from simple calculation.

It's going to be hard to create a well-corrected fl=70mm and dia = 39mm lens group. Type-1/3" CCD is used in the illustration.

Also note that the calculation is based on the OTA itself can offer a huge image circle to begin with. In real life, it is not. Focal Reducer cannot "fetch" light which is not offered by its feeder (the OTA) to begin with.

P.S. it's also OTA design dependent. In my example, the FR lens assembly has to go VERY far into the inside of the OTA tube (28% from the OTA's original primary focal plane) !!! Not many OTA can support that.

See attached calculation:


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ccs_hello
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Re: Focal Reducer for Video SCT SCopes down to F/1.5 new [Re: ccs_hello]
      #5776625 - 04/03/13 10:15 PM Attachment (16 downloads)

let's try 0.15x:
Not completely impossible from simple calculation.

It's going to be hard to create a well-corrected fl=60mm and dia = 39mm lens group.

P.S. it's also OTA design dependent. In my example, the FR lens assembly has to go VERY far into the inside of the OTA tube (34% from the OTA's original primary focal plane) !!! Not many OTA can support that.
It's parameter "D", in line 36.

See attached calculation:


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ccs_hello
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Re: Focal Reducer for Video SCT SCopes down to F/1.5 new [Re: jimthompson]
      #5776641 - 04/03/13 10:22 PM

Jim,

See links in post #1 and #9 in this CN thread.

Clear Skies!

ccs_hello


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GlennLeDrew
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Re: Focal Reducer for Video SCT SCopes down to F/1.5 new [Re: ccs_hello]
      #5776994 - 04/04/13 04:07 AM

Jim,
Good ol' ccs beat me to it, and good thing, too, because I don't have the spreadsheet he's used. I was going to fall back on the basic formulae.

To summarize the particulars for the 0.15X reducer, as calculated by ccs_hello above for a 100mm f/10 scope.

The reducer must itself have a pretty fast f/ratio. The 'recipe' here is for the reducer being a 39mm f/1.54. (Off-the-shelf reducers are typically f/2.5-4.)

Compared to the 1,000mm scope focal length, the reducer must be located fully 340mm inside the f/10 focus position. For a Cat of only 100mm aperture, that would put it essentially in contact with the secondary mirror, which is of course a ridiculous location.

The camera's chip has to be only 51mm behind the reducer, placing it also near the secondary.

Finally, no more than 20% of he chip is fully illuminated, and so vignetting will be notable.

If employing this reducer on other f/10 scopes, the distances the reducer and detector must be moved forward of the 'native' f/10 focus will be essentially identical. Meaning they will certainly be located well up in the primary baffle for even large SCTs.

Now, if one wanted to get really sophisticated, transfer lenses could be installed inside the primary baffle so as to place the 'native' f/10 focus sufficiently far outside the back end so that the reducer could be located at or just behind the exit aperture of the primary baffle. But that's getting quite complicated!


To answer your more general questions.

The light cone behind the reducer has the solid angle appropriate to the final, working f/ratio.

For a given reducer, as the reduction factor is increased:
- The reducer moves closer to the objective.
- The detector moves back farther behind the reducer, but
- The detector does also move toward the objective, just a little more slowly than does the reducer.

In order to not suffer more inward placement than necessary, the reducer must be made as small as possible, commensurate with the detector's size. And the faster the desired working f/ratio at the detector, the faster must be the reducer itself.

To first order, the reducer's clear aperture should not be less than

1 / reduction factor * the detector width.

(At least it holds fairly well for 'simple' reducers; compound reducers (of which the two-piece MFR-5 is a good example) may well introduce some complications.)

For example, a 0.5X reducer used with a 25mm wide CCD should have a clear aperture of

1 / 0.5 * 25 = 50mm

This will keep vignetting to a reasonable level.


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nytecam
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Re: Focal Reducer for Video SCT SCopes down to F/1.5 new [Re: GlennLeDrew]
      #5778066 - 04/04/13 04:25 PM

Just a thought but anyone considered/ tried John Wall's Hyperchromatic Refractor featured on the ATM Forum last April? Effectively it's a stacked long and short focus refractors giving a fast 'speed' but light collecting power of the large front objective which can be a simple[?] plano-convex lens with apparently minimal CA. May help our light-hungry video cams

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GlennLeDrew
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Re: Focal Reducer for Video SCT SCopes down to F/1.5 new [Re: nytecam]
      #5778219 - 04/04/13 05:54 PM

Maurice,
Wall's design you point to is a visual scope, primarily. It's speed is determined by the doublet objective (which works exactly like a focal reducer) which in the end gets no faster than about f/3. Moreover, there is significant lateral color present, due to the big singlet lens up front.

I think that in this incarnation it's a dead end as a fast imaging system.


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nytecam
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Re: Focal Reducer for Video SCT SCopes down to F/1.5 new [Re: GlennLeDrew]
      #5778973 - 04/05/13 04:11 AM

Quote:

Maurice, Wall's design you point to is a visual scope, primarily. It's speed is determined by the doublet objective (which works exactly like a focal reducer) which in the end gets no faster than about f/3. Moreover, there is significant lateral color present, due to the big singlet lens up front. I think that in this incarnation it's a dead end as a fast imaging system.


Glenn - I read your largely negative contribution to that ATM thread but to be fair you weren't alone in that. However like much in this field it's best-to-test rather than rely on theory alone via raytracing or what is often idle internet comment.

Outside the lab effects of seeing, tracking, pixel scale etc cause some inevitable relaxing of standards below perfection. I delayed my Littrow spectroscope and Lensless Schmidt camera because I saw told "it wouldn't work" but both worked just fine. I'd give the doers credit before any theorist.

I just thought that astrovideographers hereabouts, who I suspect are not all theoretical perfectionists, would benefit from the Hyper article.


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GlennLeDrew
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Re: Focal Reducer for Video SCT SCopes down to F/1.5 new [Re: nytecam]
      #5780200 - 04/05/13 05:23 PM

Maurice,
My comments on Wall's Hypo design were based on both the data and images supplied by Jon himself. He clarified that the aberrations limited it to a lowest power visual instrument.

Why make up a long refractor whose light collector is an f/40 singlet, followed by binocular objective acting as a focal reducer, delivering only an f/3 image plagued by wicked lateral color and still-significant longitudinal color?

FAR better optically, readily available, and much more compact; a cheap f/4 Newt with a $30 0.5-0.7X reducer. Or an inexpensive f/5 achromat with the same reducer at 0.5X.


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mattflastro
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Re: Focal Reducer for Video SCT SCopes down to F/1.5 new [Re: GlennLeDrew]
      #5799883 - 04/15/13 04:53 AM

Quote:

Chris,
If embellishment, adornment or even fakery is intended, then it's a *lot* simpler to substitute an image taken with even a rather different rig but which has the image scale of the intended 'simulated' view...

Matt,
If you wish not to have such speculation continue, then at least let us know if you're indeed developing (or helping to develop) something which eventually will be available commercially. To drop a 'teaser' and then clam up with the "not for the public domain" brush-off is not consistent with a 'Skunk Works' project for which you have not oversight or signing authority. And so it stands to reason that you're the one answerable, and can only do yourself a favor by providing even a smidgen of supportable clarification.

And what about the state of the camera you also 'teased' us with a little while back? Is it to be considered in the same category?




Any of the group experts or anyone from this group for that matter, if you happen to be in or travel to south east Florida, I'd be happy to meet and demonstrate one evening the reducer and camera.
Otherwise I'll let you know when production starts and more info will then be available .


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GlennLeDrew
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Re: Focal Reducer for Video SCT SCopes down to F/1.5 new [Re: mattflastro]
      #5801073 - 04/15/13 05:32 PM

If you're willing to demo in person, then why not a *little* detail here, sufficient to allay doubts yet not compromise any proprietary aspects?

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Lorence
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Re: Focal Reducer for Video SCT SCopes down to F/1.5 new [Re: mattflastro]
      #5802855 - 04/16/13 02:25 PM

Quote:

Any of the group experts or anyone from this group for that matter, if you happen to be in or travel to south east Florida, I'd be happy to meet and demonstrate one evening the reducer and camera. Otherwise I'll let you know when production starts and more info will then be available .




As I'm not expert enough to speculate about equipment, I'll just buy it. You win some and you loose some but at least you end up knowing. That beats the alternative and I don't have to spend all day on the forums.

I would like to preorder one of your cameras and focal reducers. I used the term "like" simply because you haven't quite achieved Rock's reputation in the astro video camera business yet.

I already have a pile of cheap cameras for Lunar and planetary so I'm sure you can understand I am only in the market for high end products.

If your camera is in the Mallincam Xtreme or Universe class my order stands. Otherwise I wish you the best of luck with this camera, hopefully you will be successful enough with it to move on to bigger and better cameras. If it is a low end class camera just keep the price down. It seems that is the main criteria for camera selection by many.


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GlennLeDrew
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Re: Focal Reducer for Video SCT SCopes down to F/1.5 new [Re: Lorence]
      #5803756 - 04/16/13 11:59 PM

I would be hard pressed to refrain from countering the nay-saying of 'forum experts' (like myself ) if I had found a way to achieve the Holy Grail of taking an f/10 system down to f/1.5 with a back-end focal reducer.

That a hobbyist can cobble up from existing lenses such an astounding optical wonder which seems to be beyond the capability of professional designers to offer (at anything like a non-astronomical price, if achievable) would be cause to rightfully crow to high heaven and bask in the ensuing avalanche of plaudits and laurels.

My feeling is that it might well be the case that the *image scale* reduction is occurring, but virtually certainly not at full system aperture. For example, a 10" SCT might be working at nearer to 6" aperture. This notwithstanding, the lack of apparent vignetting and any notable off-axis aberration, for such aggressive reduction, raises a big red flag.

I wonder if the device is actually an afocal imaging system, which would employ a fast, somewhat short focal length lens on the camera, shooting into an eyepiece...


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ccs_hello
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Re: Focal Reducer for Video SCT SCopes down to F/1.5 new [Re: GlennLeDrew]
      #5803813 - 04/17/13 12:58 AM

Indeed, placing a lens "before" the primary focal plane is the preferred way to modify an existing optical system's parameters. E.g., (per definition,) placing a negative lens inside focal plane, it is a Barlow; placing a positive lens inside focal plane, it is a Focal Reducer.

Placing a lens "after" the primary focal plane is afocal method. Placing a positive lens (or even a common magnifier), e.g., using an eyepiece, is an eyepiece projection (similar to Barlow effect.)
On the same token, replacing that positive lens with a negative lens will reduce the image scale.

Do an experiment, place a Barlow lens in between a piece of newspaper and your eye, you'll find the text looks tinier.

Clear Skies!

ccs_hello


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mattflastro
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Re: Focal Reducer for Video SCT SCopes down to F/1.5 new [Re: ccs_hello]
      #5867978 - 05/17/13 07:30 PM Attachment (25 downloads)

Here are the first 3 prototypes of my focal reducer.
Why 3? Due to lack of enough planning .
I started by making focal reducer #1 to be compatible with my C-mount cam #1.
Then I made focal reducer #2 as a cleaner version ( #1 has a lot of rework and modifications due to experimenting) .
Then I decided to make camera #2 with Peltier cooling and T-mount .
Then I had to redo focal reducer #1 and modify it to work with both the T-mount and the C-mount .
So then I made reducer #3 that works from the beginning with both C and T mounts . I also made it fit any 2" focuser instead of just the MEade 3.25" threads.


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mattflastro
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Re: Focal Reducer for Video SCT SCopes down to F/1.5 new [Re: mattflastro]
      #5867981 - 05/17/13 07:33 PM Attachment (26 downloads)

Another pic below.
I need to mention that these focal reducers that bring an 8 to 12" F/10 SCT down to F/1.85 are NOT a simple doublet or triplet. They are multielement reducers with an ED glass element and were optimised in Oslo before being tested .
The #3 is close to a final version, except for finishing which is still a rough prototype. Final version will get all the normal treatments, blackened lens edges, hard anodizing etc.


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Atl
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Re: Focal Reducer for Video SCT SCopes down to F/1.5 new [Re: mattflastro]
      #5868513 - 05/18/13 12:05 AM

Very cool.

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nytecam
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Re: Focal Reducer for Video SCT SCopes down to F/1.5 new [Re: Atl]
      #5868704 - 05/18/13 03:02 AM

Looks very interesting - thanks for posting

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Re: Focal Reducer for Video SCT SCopes down to F/1.5 new [Re: nytecam]
      #5868737 - 05/18/13 03:56 AM

Are these adaptations of existing camera lenses? The barrels and lens coatings give the appearance of surplus stuff from the '70s or '80s.

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mattflastro
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Re: Focal Reducer for Video SCT SCopes down to F/1.5 new [Re: GlennLeDrew]
      #5869802 - 05/18/13 05:47 PM

Quote:

Are these adaptations of existing camera lenses? The barrels and lens coatings give the appearance of surplus stuff from the '70s or '80s.



Sorry but barrels are not 70's or 80's surplus.
I thought you wouldn't have trouble recognising the stuff that happened to BE recycled.
For the #1 and #2 , they are simply reworked MEade and Celestron T-mount adapters of current production (the Celestron is the HD T-mount adapter).


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mattflastro
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Re: Focal Reducer for Video SCT SCopes down to F/1.5 new [Re: GlennLeDrew]
      #5869816 - 05/18/13 05:53 PM

Quote:

Are these adaptations of existing camera lenses? The barrels and lens coatings give the appearance of surplus stuff from the '70s or '80s.



Also, the aged aspect of #1 is due to being banged around in numerous trips between machine shop and field tests . Anodizing and paint weren't that great to begin with , and when you assemble and disassemble then clamp a piece and turn it or mill it then go back and repeat the cycle , after a while it starts looking like war surplus.


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JoseBorrero
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Re: Focal Reducer for Video SCT SCopes down to F/1.5 *DELETED* new [Re: GlennLeDrew]
      #5882943 - 05/24/13 07:15 PM

Post deleted by JoseBorrero

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budman1961
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Re: Focal Reducer for Video SCT SCopes down to F/1.5 new [Re: JoseBorrero]
      #5882973 - 05/24/13 07:29 PM

Per his site Jose....

WARNING! THESE FOCAL REDUCERS ARE DESIGNED STRICTLY FOR THE LNTECH CAMERAS, MODEL LN300 AND FOR OUR COOLED T-MOUNT CAMERAS. THEY WILL NOT WORK WITH ANY OTHER CAMERA WITHOUT MODIFICATION. THESE REDUCERS EMPLOY THE MOST AGGRESSIVE, HIGHEST REDUCTION FACTOR THAT IS POSSIBLE GIVEN THE TELESCOPE CHARACTERISTICS, CCD SIZE AND REDUCER TO SENSOR CORRECT SPACING. IT MAY BE POSSIBLE TO MODIFY THE FOCAL REDUCERS TO WORK WITH OTHER 1/3" CCD CAMERAS. CONTACT US FOR MORE DETAILS. WE WILL NEED TO MEASURE YOUR CAMERA MOUNT-FLANGE TO SENSOR DISTANCE TO ANALYZE IF A SPACER COULD BE MODIFIED TO ACCOMODATE THE REDUCER REQUIREMENTS.


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GlennLeDrew
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Re: Focal Reducer for Video SCT SCopes down to F/1.5 new [Re: budman1961]
      #5882989 - 05/24/13 07:37 PM

Some questions...

What is the sensor depth requirement?

How many lens elements/groups comprise the reducer?

What is the reducer's focal length?

Does this reducer utilize the full aperture of the entrance pupil?

Considering the assembled length, does this result in the primary mirror having to be moved toward the secondary sufficiently far to result in aperture reduction due to clipping by one or both baffles?

What is the diameter of the small-ish aperture at the rear of the unit?

On the "technology" page of the site--where no more technology than found on the main page is discussed--an image clearly taken with other than a 1/3" camera is used to illustrate field coverage. Will actual images obtained via this reducer onto a 1/3" camera be added?

Furthermore, will comparison images be provided so as to illustrate the speed differential? Such as 60s @ f/10 and 2s @ f/1.8 (other settings remaining the same)?


A photo or two looking down the front end of the scope through the assembled system, when set to infinity focus, and with the CCD illuminated, would be instructive. Or just a view straight into just the reducer while attached to a camera.

Edited by GlennLeDrew (05/25/13 04:25 PM)


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GlennLeDrew
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Re: Focal Reducer for Video SCT SCopes down to F/1.5 new [Re: GlennLeDrew]
      #5884343 - 05/25/13 04:56 PM

Bumped because of added questions to the above post...

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a__l
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Re: Focal Reducer for Video SCT SCopes down to F/1.5 new [Re: mattflastro]
      #5896827 - 06/01/13 09:36 PM

Quote:

Hyperstar is an option that gets down to F/2 .
Meade .33x gets down to F/3.3 .
I am not aware of any other options that could be used , which should not involve disassembling the corrector and buying $1000 worth of mechanical+optical parts .
The image below is shot with my home made reducer and my Meade 10 inch F/10 SCT .
The result is F/1.55 apparently (I might be off by a little, actual range based on transit time is 1.5 to 1.6 ) .
Is there anything like this available commercially ?
Please note that my reducer can NOT work with cameras that have a CCD any larger than 1/3" ( 6mm diagonal).




Interesting info (in Russian) and schedule.
The sensitivity of ICX-413AQ and F/D. web page
At very fast reducer, you will lose in the sensitivity matrix.


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Re: Focal Reducer for Video SCT SCopes down to F/1.5 new [Re: a__l]
      #5897069 - 06/02/13 12:00 AM

This light cone steepness impact to digital image sensor is well known. Some mfgs' marketing department specifically made that point stating their lenses are resigned as "digital lens" as opposed to film SLR lenses.

The underlying reason is the image sensor's microlens design. Later sensors made a little bit of improvement on sensor's optical path.

The "special designed" digital lens' rear group attempts to realign the light beam to be as perpendicular to the sensor plane as possible. Naturally it's not the case on a telescope OTA with a F.R. "modifier".

My take: since there is nothing we can do to fix the sensor design, why not just keep on shooting. (E.g., at f/1.8, ICX413's microlens' efficiency only drops 18%.

Clear Skies!

ccs_hello


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a__l
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Re: Focal Reducer for Video SCT SCopes down to F/1.5 new [Re: ccs_hello]
      #5897084 - 06/02/13 12:13 AM

at f/1.5, ICX413's microlens efficiency drops about 40%

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Re: Focal Reducer for Video SCT SCopes down to F/1.5 new [Re: a__l]
      #5897162 - 06/02/13 01:15 AM

The steeper light cone angles created by aggressive focal reducers have a number of undesirable effects ...

1) reduced light transmission because of the microlens architecture - as discussed above, not much anyone can do about this.
2) reduced light transmission caused by aperture reduction (edge fall off) - requires larger aperture focal reducers, up to a point at which the telescope's inherent design characteristics become the restriction.
3) changes in filter transmission characteristics - can be solved by placing the filter(s) in front of the focal reducer but this can become problematic if the reducer is a larger aperture type or uses an unusual mounting arrangement.


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nytecam
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Re: Focal Reducer for Video SCT SCopes down to F/1.5 new [Re: a__l]
      #5897301 - 06/02/13 04:20 AM

Quote:

My take: since there is nothing we can do to fix the sensor design, why not just keep on shooting. (E.g., at f/1.8, ICX413's microlens' efficiency only drops 18%. ccs_hello

at f/1.5, ICX413's microlens efficiency drops about 40% - a__l


That's a shame - I'd forgotten about on-pixel microlensing limits.

Must admit I was concerned about sucking up more LP with superfast optical systems - So for me it's carry-on-regardless @ f/3.6 as before on M27 and M13 and fullsize here



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mattflastro
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Re: Focal Reducer for Video SCT SCopes down to F/1.5 new [Re: ccs_hello]
      #5897671 - 06/02/13 11:35 AM

Quote:

This light cone steepness impact to digital image sensor is well known. Some mfgs' marketing department specifically made that point stating their lenses are resigned as "digital lens" as opposed to film SLR lenses.

The underlying reason is the image sensor's microlens design. Later sensors made a little bit of improvement on sensor's optical path.

The "special designed" digital lens' rear group attempts to realign the light beam to be as perpendicular to the sensor plane as possible. Naturally it's not the case on a telescope OTA with a F.R. "modifier".

My take: since there is nothing we can do to fix the sensor design, why not just keep on shooting. (E.g., at f/1.8, ICX413's microlens' efficiency only drops 18%.

Clear Skies!

ccs_hello



There is no problem here.
At F1.8 my FR loses 18% compare to the non reduced F10 scope and loses about 13% compared to the F3.3 reducer.
At the same time, my F1.8 reducer makes the system 30 times faster , which combined with the 18% loss yields a 26.4 times faster system vs. the original F10 (instead of the theoretical maximum of 30) .
A practical example of the effect magnitude is as follows:
- if I had to integrate at F10 for 1 minute , I'd have to integrate for 2 seconds with an "ideal" (meaning no light loss due to fast F-ratio on the microlenses) , and I'd have to integrate 2.2 seconds with the real reducer . I'd take any time the extra .2 seconds instead of the 1 minute.


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Dwight J
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Re: Focal Reducer for Video SCT SCopes down to F/1.5 new [Re: mattflastro]
      #5897805 - 06/02/13 01:07 PM

More is better until it is too much.

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mattflastro
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Re: Focal Reducer for Video SCT SCopes down to F/1.5 new [Re: Dwight J]
      #5897946 - 06/02/13 02:28 PM

Quote:

More is better until it is too much.



Generally a wise statement but how does it apply here? I've never heard anybody saying gee, I wish I had a less sensitive camera, or I wish I didn't see this target in just a few seconds, I was hoping it'd take longer so I could have some time to watch the grass grow...
I can only see the normal limitations of ANY device , meaning there's no single tool that fits all situations . Some times in order to best frame a target you need a barlow, sometimes a moderate reducer such as an F6.3 or 3.3, and sometimes a F1.8 reducer. Different tools that just increase the versatility of SCT scopes . I don't think any SCT owner would complain about this .


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Re: Focal Reducer for Video SCT SCopes down to F/1.5 new [Re: mattflastro]
      #5898047 - 06/02/13 03:18 PM

As long as the increase in surface brightness with decreasing f/ratio proceeds faster than the decrease in sensor efficiency, you're ahead of the curve and all's fine. I see no f/ratio we'd ever use where the efficiency decrease would actually be disadvantageous. (Excluding angle-of-incidence issues for narrow band filters, of course!)

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Re: Focal Reducer for Video SCT SCopes down to F/1.5 new [Re: GlennLeDrew]
      #5898050 - 06/02/13 03:20 PM

Matt,
Have you gotten around to testing your reducer for potential aperture reduction, along the lines of my own in my "fast focal reduction testing" thread?


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nytecam
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Re: Focal Reducer for Video SCT SCopes down to F/1.5 new [Re: mattflastro]
      #5898053 - 06/02/13 03:21 PM

Well said Matt eg small percentage exposure increases we can take in our stride in the brief exposures we use

Did a comparison of my Lodestar mono and colour cams and whilst the unfiltered mono cam is obviously faster it is not dramatically so due to the pale CMYG complimentary on-pixel filters on the colour cam needing an exposure increase eg 60s mono to 100s colour for similar image density. This is further aided by the infra-red sensitivity of these cams when the IR filter is removed or not used giving an overall boost in sensitivity. The dense RGB on-chip filters, typical in DSLR [and Universe cams?] etc take a heavier toll on exposure durations


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Re: Focal Reducer for Video SCT SCopes down to F/1.5 new [Re: GlennLeDrew]
      #5898071 - 06/02/13 03:28 PM

Quote:

Matt,
Have you gotten around to testing your reducer for potential aperture reduction, along the lines of my own in my "fast focal reduction testing" thread?



Ther's no potential apreture reduction in the way my focal reducer was designed . It was tested thru appropriate methods too.


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GlennLeDrew
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Re: Focal Reducer for Video SCT SCopes down to F/1.5 new [Re: mattflastro]
      #5898093 - 06/02/13 03:46 PM

How about providing a photo to really press home the point with proof one can see? For us "doubting Thomases." Just one image, where the sight line has the visible edge of the CCD aligned with the edge of the primary will suffice.

I am still somewhat skeptical because of the potential degree that the focus has been moved rearward, and the somewhat forward distance at which the reducer's front lens seems to reside with respect to the rear lens/focus. These two factors are very potential causes of aperture reduction.

And there's nothing like actual examination in situ to verify theory.


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mattflastro
Vendor - Astrovideo Systems


Reged: 07/31/09

Loc: Brevard County , FL
Re: Focal Reducer for Video SCT SCopes down to F/1.5 new [Re: GlennLeDrew]
      #5898119 - 06/02/13 04:09 PM

Quote:

How about providing a photo to really press home the point with proof one can see? For us "doubting Thomases." Just one image, where the sight line has the visible edge of the CCD aligned with the edge of the primary will suffice.

I am still somewhat skeptical because of the potential degree that the focus has been moved rearward, and the somewhat forward distance at which the reducer's front lens seems to reside with respect to the rear lens/focus. These two factors are very potential causes of aperture reduction.

And there's nothing like actual examination in situ to verify theory.



Glenn, I understand what you're saying but there's nothing more I would add before I actually start selling them. After I start selling , I'd be glad to hear feedback and see pics taken with it by users and anyone else who wants to test them.

Edited by mattflastro (06/02/13 04:10 PM)


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Dwight J
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Re: Focal Reducer for Video SCT SCopes down to F/1.5 new [Re: mattflastro]
      #5900842 - 06/03/13 11:44 PM

If you would like to sell these Matt, some images taken with one of your modified cameras and focal reducers posted here or on your website would help sell them. All we have seen is the moon which is not a good litmus test. Or are buyers lining up now?

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mattflastro
Vendor - Astrovideo Systems


Reged: 07/31/09

Loc: Brevard County , FL
Re: Focal Reducer for Video SCT SCopes down to F/1.5 new [Re: Dwight J]
      #5900903 - 06/04/13 12:27 AM

Quote:

If you would like to sell these Matt, some images taken with one of your modified cameras and focal reducers posted here or on your website would help sell them. All we have seen is the moon which is not a good litmus test. Or are buyers lining up now?



You worry too much for me , thanks.


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CuriousOne
member


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Re: Focal Reducer for Video SCT SCopes down to F/1.5 new [Re: GlennLeDrew]
      #5900952 - 06/04/13 01:03 AM

I have a lot of microscope oculars, front lens aseembles, camera lens (photo/video/security), gun sights, binocular oculars and so on. Is it possible to homebrew a 0.4X reducer for 1/3 CCD, so my 1000mm/F10 will became 400mm/F4 ?

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budman1961
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Re: Focal Reducer for Video SCT SCopes down to F/1.5 new [Re: CuriousOne]
      #5900973 - 06/04/13 01:22 AM

Matt,

So you want to sell cameras and focal reduces without any images ........good luck. The proof is in the pudding, or in this case, not.


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Tom and Beth
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Re: Focal Reducer for Video SCT SCopes down to F/1.5 new [Re: budman1961]
      #5900986 - 06/04/13 01:40 AM

Quote:

Matt,

So you want to sell cameras and focal reduces without any images ........good luck. The proof is in the pudding, or in this case, not.




Hmm, as somebody who has no dog in this hunt...on the Vendor page, right under his note that there are none for sale yet, a note about all specs will be released after his patent filing.

Hey, maybe it really is vaporware. Maybe not.

It'll be interesting to see who has pudding on their face.


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Astro Sky
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Re: Focal Reducer for Video SCT SCopes down to F/1.5 new [Re: mattflastro]
      #5901446 - 06/04/13 10:23 AM

Money back if not satisfied?

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mattflastro
Vendor - Astrovideo Systems


Reged: 07/31/09

Loc: Brevard County , FL
Re: Focal Reducer for Video SCT SCopes down to F/1.5 new [Re: Astro Sky]
      #5901547 - 06/04/13 11:10 AM

Quote:

Money back if not satisfied?



Standard 30 days money back and 1 year warranty for the reducers when they start selling.


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GlennLeDrew
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Re: Focal Reducer for Video SCT SCopes down to F/1.5 new [Re: CuriousOne]
      #5901842 - 06/04/13 01:39 PM

Quote:

I have a lot of microscope oculars, front lens aseembles, camera lens (photo/video/security), gun sights, binocular oculars and so on. Is it possible to homebrew a 0.4X reducer for 1/3 CCD, so my 1000mm/F10 will became 400mm/F4 ?




Given the smaller sensor in the 1/3" format, your chances are good. 0.4X is considered fairly aggressive. A pair of f/3.5-4 achromats, each having a focal length no longer than about 80mm, should do the job. The real trick is making up a housing for them...


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GlennLeDrew
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Re: Focal Reducer for Video SCT SCopes down to F/1.5 new [Re: GlennLeDrew]
      #5901876 - 06/04/13 02:00 PM

My main concern remaining to be answered regarding Matt's über fast reducer is that it works at least reasonably close to full aperture. Meeting this condition *and* maintaining good correction with minimal vignetting using off-the-shelf lenses would seem to be a difficult proposition. That's a lot of shaping of the wavefront into a very steep cone using *presumably* spherical elements.

Nonetheless, with lens data in hand and the power of Zemax, a selection of lenses could, I suppose, be fashioned into such a device. But I'd rather some proof, in the form of a star field image for performance re. aberrations and vignetting, and either a ray trace or photo taken through the edge of the aperture to show accommodation of image forming light from the entrance pupil.

Why has no other optical firm offered for f/10 SCTs a reducer faster than ~0.3X? Small-chip cameras have been in use for a good two decades.


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Astro Sky
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Re: Focal Reducer for Video SCT SCopes down to F/1.5 new [Re: mattflastro]
      #5901877 - 06/04/13 02:00 PM

Quote:

Quote:

Money back if not satisfied?



Standard 30 days money back and 1 year warranty for the reducers when they start selling.





Thanks!
My friend is looking to buy a color video camera for his Meade 10" LX200 GPS.
About how long be ready to delivery?


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mattflastro
Vendor - Astrovideo Systems


Reged: 07/31/09

Loc: Brevard County , FL
Re: Focal Reducer for Video SCT SCopes down to F/1.5 new [Re: GlennLeDrew]
      #5902067 - 06/04/13 03:47 PM

Quote:

My main concern remaining to be answered regarding Matt's über fast reducer is that it works at least reasonably close to full aperture. Meeting this condition *and* maintaining good correction with minimal vignetting using off-the-shelf lenses would seem to be a difficult proposition. That's a lot of shaping of the wavefront into a very steep cone using *presumably* spherical elements.

Nonetheless, with lens data in hand and the power of Zemax, a selection of lenses could, I suppose, be fashioned into such a device. But I'd rather some proof, in the form of a star field image for performance re. aberrations and vignetting, and either a ray trace or photo taken through the edge of the aperture to show accommodation of image forming light from the entrance pupil.

Why has no other optical firm offered for f/10 SCTs a reducer faster than ~0.3X? Small-chip cameras have been in use for a good two decades.



Glenn, you have been voicing your objections to my announced product almost daily .
Is there anything in particular that you or anybody associated with you have to gain by doing this ?
You are obviously not adding anything new just keep repeating that you have concerns .
I explained the reason for not adding any more details.
Any reasonable person in good faith would understand and STOP making negative or harmful comments that are bordering slander , at least until you get to see the actual product.
After that, I'm looking forward to a very thorough review from any knowledgeable interested party.
Until then, please refrain from making any more negative comments just for their psychological effect .
It shouldn't be hard, since as I said earlier, you are not adding anything new to your frequently posted doubts , so I'm not asking you to keep secrets .

As for the reason why aren't other companies offering such a reducer , I'm not those other companies and don't know.

Does your logic tell you that products that haven't been offered yet are impossible and therefore they could not and should not be offered in the future , for the simple reason that nobody sold them in the past ?


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GlennLeDrew
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Re: Focal Reducer for Video SCT SCopes down to F/1.5 new [Re: mattflastro]
      #5902338 - 06/04/13 06:13 PM

Matt,
I hardly think I'm verging on slander. I'm merely expressing some doubts based on existing solutions, and what experience and knowledge I might possess. In your shoes I'd be showing unambiguous results and proofs, and trying to address concerns. It puzzles me that you're not willing to do this.

In my previous post I did concede that it's conceivable that a selection of ready-made lenses could be made to work in this fashion, when the relevant data are known and the power of Zemax is brought to bear. I'm not *entirely* dismissive, just skeptical about the totality of performance, specifically the useage of the full entrance pupil.

I'll be the first to heap plaudits and rain down accolades once my concerns are proved unfounded and laid to rest.


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mattflastro
Vendor - Astrovideo Systems


Reged: 07/31/09

Loc: Brevard County , FL
Re: Focal Reducer for Video SCT SCopes down to F/1.5 new [Re: GlennLeDrew]
      #5902370 - 06/04/13 06:37 PM

Quote:

Matt,
I hardly think I'm verging on slander. I'm merely expressing some doubts based on existing solutions, and what experience and knowledge I might possess. In your shoes I'd be showing unambiguous results and proofs, and trying to address concerns. It puzzles me that you're not willing to do this.

In my previous post I did concede that it's conceivable that a selection of ready-made lenses could be made to work in this fashion, when the relevant data are known and the power of Zemax is brought to bear. I'm not *entirely* dismissive, just skeptical about the totality of performance, specifically the useage of the full entrance pupil.

I'll be the first to heap plaudits and rain down accolades once my concerns are proved unfounded and laid to rest.



No it doesn't "puzzle you" that I'm not telling more.
You kow full well that I CAN'T disclose more than I already said . So you keep harping on this theme knowing full well that I CAN'T say anything . You're not doing this in good faith . If you had a device that you were trying to patent you wouldn't be blurting out details to "address concerns".


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budman1961
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Re: Focal Reducer for Video SCT SCopes down to F/1.5 new [Re: mattflastro]
      #5902498 - 06/04/13 07:46 PM

Well, time for me to chime in. If you dont have the patent in place, why are the items for sale? Surely you cant expect people fork over any cash without any images taken with said patent-pending gadgets?

I guess the interesting thing is your pushback when asked completely reasonable questions.....claiming slander and such. I'm sure Mr. Mallin felt the same way when you tried to drag him and his products through the mud.

You reap what you sow, and who appointed you moderator anyway?


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mclewis1
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Re: Focal Reducer for Video SCT SCopes down to F/1.5 new [Re: mattflastro]
      #5902537 - 06/04/13 08:03 PM

Matt, I don't think anyone is seriously suggesting that you have to explain in any way the how of what you are doing. I'm sure Glenn and others might like to know but so what, it's your product and your potential patent. The real question is the result. Is posting some simple photographs that illustrate the lack of aperture reduction and star field performance really such a problem?

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GlennLeDrew
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Re: Focal Reducer for Video SCT SCopes down to F/1.5 new [Re: mclewis1]
      #5902602 - 06/04/13 08:39 PM

There are ways to demonstrate the aspects of performance I'm addressing from which no one could possibly divine proprietary information. In my thread about fast focal reducer testing, I describe and illustrate a method by which a qualitative assessment of entrance pupil accommodation can be easily obtained. From such a series of images alone, it would be utterly impossible to derive in any way whatsoever the optical configuration.

I'm not trying to maneuver you, Matt, into divulging a scrap of proprietary info. I merely wish to see some confidence-building evidence of claimed performance. Which can be provided so easily and in a manner consistent with the preservation of 'secrecy.'

Incidentally, did not this thread commence before your vendor status? I seem to recall the early going as being that of a hobbyist, but I may be mistaken...


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David B in NM
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Re: Focal Reducer for Video SCT SCopes down to F/1.5 new [Re: budman1961]
      #5902619 - 06/04/13 08:48 PM

Quote:

Well, time for me to chime in. If you dont have the patent in place, why are the items for sale? Surely you cant expect people fork over any cash without any images taken with said patent-pending gadgets?

I guess the interesting thing is your pushback when asked completely reasonable questions.....claiming slander and such. I'm sure Mr. Mallin felt the same way when you tried to drag him and his products through the mud.

You reap what you sow, and who appointed you moderator anyway?




I suggest you calm down and read what is posted on his website. If you read what is posted on the link below, you will see these words:

This F1.8 focal reducer product is not available for sale yet.
It will be available for sale , together with all user manuals , specifications and other information as soon as my US Patent filing process for it is completed .

Here is the link: Website

I suggest you allow Mr. Mallin speak for and represent himself on this Forum.

There's no reason you need to continue to attack Matt for something that occurred between he and Mr. Mallin. Continued attacks against Matt do nothing to benefit this forum.

Is it possible for everyone to act like an adult?

David B in NM


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Undermidnight
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Re: Focal Reducer for Video SCT SCopes down to F/1.5 new [Re: David B in NM]
      #5902626 - 06/04/13 08:54 PM

Ok guys, it's time to tone it down. Let's move on and get past the recent posts. I for one hope that Matt's products are successful (as well as Rock's products) because we all win in the end as potential future customers. Once Matt is ready to reveal more, he will. In the meantime, please keep this civil or the thread gets locked.

Thanks for your understanding and continued (civil ) participation..

Jason


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GlennLeDrew
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Re: Focal Reducer for Video SCT SCopes down to F/1.5 new [Re: Undermidnight]
      #5903237 - 06/05/13 05:34 AM

If the reducer design has been settled upon, and is that which will be employed in the final design, then any questions regarding its performance are completely valid. If the concerns raised by potential customers regarding a product proffered by a vendor are out of bounds, then political correctness has been carried to a degree which can only be characterized as extreme.

Anyone who desires to part me from my hard-earned cash must do better than address my questions with "buy it and test that which I refuse to reveal." I could not conceive of such an attitude were I to be selling a piece of equipment.


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GlennLeDrew
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Re: Focal Reducer for Video SCT SCopes down to F/1.5 new [Re: GlennLeDrew]
      #5903314 - 06/05/13 07:17 AM

A vendor--that entity which would part us from our money--should expect to have their feet held to the fire, when legitimate questions are asked.

Edited by GlennLeDrew (06/05/13 04:41 PM)


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telfish
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Re: Focal Reducer for Video SCT SCopes down to F/1.5 new [Re: GlennLeDrew]
      #5903388 - 06/05/13 08:25 AM

For heavens sake!

Just wait until he has them actually on the market and buy one. He says he will refund if you are unhappy.

Just stop the McCarthyism.


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core
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Reged: 02/23/08

Loc: Mostly in Norman, OK
Re: Focal Reducer for Video SCT SCopes down to F/1.5 new [Re: telfish]
      #5910802 - 06/09/13 02:51 AM

This particular sub-forum seem to routinely generate quite a bit of polarizing opinions and gets visited by vocal/assertive/etc individuals, and imo leans towards the "just buy/use it and don't ask any detailed questions", rather than an open forum for ATM/DIY knowledge sharing. I don't see how Glenn's thoughtful questions (and other posts which detail ways to measure/show effective aperture) would be compared to McCarthyism, exposing IP secrets, and the likes. "Extraordinary claims require extraordinary evidence"

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budman1961
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Re: Focal Reducer for Video SCT SCopes down to F/1.5 new [Re: core]
      #5911084 - 06/09/13 10:09 AM

I still can't believe that a product is being announced in the vendor forum, and whenever requests are made for some sample images, they are shouted down. What is really going on here?

Telfish, i'd suggest quitting the name calling, it doesn't help anything.


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Tom and Beth
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Re: Focal Reducer for Video SCT SCopes down to F/1.5 new [Re: budman1961]
      #5911383 - 06/09/13 01:59 PM

`

Quote:

I still can't believe that a product is being announced in the vendor forum, and whenever requests are made for some sample images, they are shouted down. What is really going on here?

Telfish, i'd suggest quitting the name calling, it doesn't help anything.




Neither does the constant whining, IMO.


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Tom and Beth
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Re: Focal Reducer for Video SCT SCopes down to F/1.5 new [Re: core]
      #5911406 - 06/09/13 02:07 PM

Quote:

This particular sub-forum seem to routinely generate quite a bit of polarizing opinions and gets visited by vocal/assertive/etc individuals, and imo leans towards the "just buy/use it and don't ask any detailed questions", rather than an open forum for ATM/DIY knowledge sharing. I don't see how Glenn's thoughtful questions (and other posts which detail ways to measure/show effective aperture) would be compared to McCarthyism, exposing IP secrets, and the likes. "Extraordinary claims require extraordinary evidence"




While I agree the name calling and suggestions to "just buy it" doesn't add to a mature dialog.

The Vendor evidently doesn't want to disclose anything before a patent. This has been posted several times. Any reason why people just can't wait a "reasonable" time to see if the vendor follows through? It's not like they have your money, nor will accept it at this time.


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budman1961
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Re: Focal Reducer for Video SCT SCopes down to F/1.5 new [Re: Tom and Beth]
      #5911608 - 06/09/13 04:22 PM

Then perhaps the announcement was rather premature. No "whining" or emoticons needed.

Have a great day.


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ccs_hello
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Re: Focal Reducer for Video SCT SCopes down to F/1.5 new [Re: budman1961]
      #5911867 - 06/09/13 07:35 PM

Worthwhile to remind viewers that this thread began when mattasro was still just a regular CNer looking for solution that would benefit for his own use (and possibly the astro community.)

At some point of time, he made a choice to productize his idea/invention. Per CN rules, he will then have to become a vendor. The product is not as simple as importing the end product directly from an OEM or ODM manufacturer elsewhere then just tag it with a custom label.
(In my own experience in understanding of manufacturing process,) it is not an easy feast. It would consume a lot of time and effort, and most importantly, upfront investment that the RoI is not guaranteed.

Probably we all know the astro community is just a small market. Many vendors came from a humble beginning with a similar story to tell. May I suggest that we the friendly CNers should not need to be so harsh on a new starter when his check needs to be written upfront to make goods while risk of
not getting what has been paid out is very high, together with
perhaps the reputation.

I believe many vendors are facing the same uncertainty.
I personally thank them for their contribution to this hobby and admire their courage.

One final note: we are consumers and we are in the buyer's market. Why should we do something to deter the fruition of capitalism? It only benefits us. So...
be patient, (y) grasshopper !

Clear Skies!

ccs_hello


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jchaller
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Re: Focal Reducer for Video SCT SCopes down to F/1.5 new [Re: ccs_hello]
      #5911976 - 06/09/13 08:27 PM

Well said.

I am rooting for Matt to succeed - not for his sake but for my own. If he is successful, I have the opportunity to purchase equipment which increases my enjoyment of this particular hobby. If he fails - for me it's disappointed hopes - for him, it's time, money, and reputation. I admire the effort he has thus far put into this endevour.



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Undermidnight
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Re: Focal Reducer for Video SCT SCopes down to F/1.5 new [Re: jchaller]
      #5912145 - 06/09/13 10:02 PM

I too am cheering Matt on with his business venture. Goodness knows how difficult it must be to get a product/business off the ground.

Jason


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mclewis1
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Re: Focal Reducer for Video SCT SCopes down to F/1.5 new [Re: Undermidnight]
      #5912824 - 06/10/13 11:13 AM

I think just about everyone is cheering for Matt's business to be successful. Nobody I know wants him to fail. Competition is a good thing for all of us customers.

Some skepticism should be expected when bold claims are made from folks without a proven track record when there's no data to back them up. If it doesn't go on for too long it really shouldn't be seen as a negative to the viability of the business. There are some good examples of other small businesses who don't do a very good job at documentation and technical data. Because of this they spend a lot of their time answering the same questions over and over again. Even after being in business for many years some of the skepticism is only contained (and ongoing sales take place) because of proven examples of performance.

Buy now or wait, sit quietly or ask questions, your choice ... but lets all hope that there are more and more cost effective choices as time goes by.


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Stew57
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Re: Focal Reducer for Video SCT SCopes down to F/1.5 new [Re: mclewis1]
      #5912828 - 06/10/13 11:15 AM

You think this is bad peruse the LX850 silence thread.

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Dwight J
scholastic sledgehammer
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Loc: Lethbridge, Alberta, Canada
Re: Focal Reducer for Video SCT SCopes down to F/1.5 new [Re: Stew57]
      #5913014 - 06/10/13 12:46 PM

Same business model.

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Atl
professor emeritus
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Re: Focal Reducer for Video SCT SCopes down to F/1.5 new [Re: Dwight J]
      #5913139 - 06/10/13 01:45 PM

I put myself out there and pre-paid for one of Matt's cameras. So far he has been good about keeping the users informed through the Yahoo group he created which has become an informative technical group in and of itself.

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Moromete
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Re: Focal Reducer for Video SCT SCopes down to F/1.5 new [Re: Atl]
      #5913387 - 06/10/13 03:35 PM

If Matt will succeed than many mouths will be shut.

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herrointment
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Re: Focal Reducer for Video SCT SCopes down to F/1.5 new [Re: Moromete]
      #5913556 - 06/10/13 04:42 PM

Best of luck to the dude.

Very entertaining thread!


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telfish
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Re: Focal Reducer for Video SCT SCopes down to F/1.5 new [Re: herrointment]
      #5913983 - 06/10/13 08:44 PM

Will the detractors eat crow pie? The suspense is electric!

Watch this space!

Go for it Matt and best of luck. American entrepreneurs will not be discouraged.


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Dwight J
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Loc: Lethbridge, Alberta, Canada
Re: Focal Reducer for Video SCT SCopes down to F/1.5 new [Re: telfish]
      #5914164 - 06/10/13 10:14 PM

Will Matt and his minions be upfront with how the equipment performs? Will there be hundreds of images posted that are simply unfooled around with? Will the equipment materialize soon? I like selective memory of how Matt was relentlessly putting the bad mouth on Mallincams here, on the Mallincam Yahoo group, and NSN claiming all the Mallincam was was a rebranded Mintron etc ( fanboys review for yourselves the relevant posts here) and now he is walking on water. I wonder if this is how competition is conducted? Put the bad mouth on the other guy asserting all forms of falsehoods and then bringing out your own line of cameras that, coincidently, don't have any of the supposed shortcomings of the competitors camera.

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Atl
professor emeritus
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Reged: 04/13/12

Re: Focal Reducer for Video SCT SCopes down to F/1.5 new [Re: Dwight J]
      #5914294 - 06/10/13 11:24 PM

I have seen the bad mouthing go both ways...all of it unnecessary. I am giving it a chance because I know a stock LN300 gives great results...adding cooling and a hand controller makes it a no brainier for the price. I quit fanboyism when I became a professional tech. I go for what works. If it works then it rocks...if it don't work it sucks.

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budman1961
Pooh-Bah
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Reged: 02/25/11

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Re: Focal Reducer for Video SCT SCopes down to F/1.5 new [Re: Atl]
      #5914340 - 06/11/13 12:02 AM

Lots of ether floating around in here..........lol

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Tom and Beth
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Reged: 01/08/07

Loc: Tucson, AZ
Re: Focal Reducer for Video SCT SCopes down to F/1.5 new [Re: budman1961]
      #5914377 - 06/11/13 12:37 AM

Quote:

Lots of ether floating around in here..........lol




Agreed. Budman1961. accept my apologies for stepping into this bull chip throwing contest. I was hoping this would end a page ago, instead ....


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Stew57
Carpal Tunnel
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Reged: 05/03/09

Loc: Silsbee Texas
Re: Focal Reducer for Video SCT SCopes down to F/1.5 new [Re: Dwight J]
      #5914394 - 06/11/13 12:53 AM

Does one have to be a "fan boy" to want to use a product? I have 2 mallincams (a vss and an EX2). I see value in the modifications Matt is doing to the cheaper cameras especially the longer integration cooled one he is proposing. It will make a good addition to the 2 mallincams. It may make a perfect finder camera. I hope the reducer performs with the camera. If it does I am in for one also depending on the price.

I am still keeping an eye out for new offerings from Rock. I am well pleased with both cameras and his service but the price is steep when you start wanting to run 4 or 5 live cameras at a time. They are also a bit wasted as finder cams.


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core
Pooh-Bah
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Reged: 02/23/08

Loc: Mostly in Norman, OK
Re: Focal Reducer for Video SCT SCopes down to F/1.5 new [Re: Stew57]
      #5914486 - 06/11/13 03:22 AM

How about back to the product in question as started in this thread, we can leave all the "specially custom made", "designed and built", "off-the-shelf modified", etc cameras to another thread

- which is, a new focal reducer design for f/10 SCT's that will bring it down f/1.5 (f/1.85?) without loosing aperture, and more or less illuminate a video sensor of a particular size

As a note, unless LNTECH LN 300 is re-housed in a different enclosure or the PCB moved up inside the existing enclosure, it spots a standard C/CS mount with flange-to-sensor distance of 17.526mm/12.5mm, so I'd take it the reducer should work with any other C/CS mount camera (not taking into account sensor size).


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Stew57
Carpal Tunnel
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Reged: 05/03/09

Loc: Silsbee Texas
Re: Focal Reducer for Video SCT SCopes down to F/1.5 new [Re: core]
      #5914503 - 06/11/13 04:06 AM

I would guess the sensor will vignette some at the size it is now and all the more if a camera with a bigger sensor is used. As long as it works with the camera he provides I would be satisfied even if the reducer is not quite compatible with other cameras due to aperture reduction.

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telfish
sage
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Reged: 11/17/10

Loc: Adirondack Mountains NY
Re: Focal Reducer for Video SCT SCopes down to F/1.5 new [Re: Stew57]
      #5914613 - 06/11/13 07:58 AM

Maybe if his products were not described as quote "vaporware" and his integrity was not called into question with zero real hard evidence then criticism of those posts would not be valid.

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nytecam
Postmaster


Reged: 08/20/05

Loc: London UK
Re: Focal Reducer for Video SCT SCopes down to F/1.5 new [Re: telfish]
      #5914752 - 06/11/13 10:06 AM

Quote:

Maybe if his products were not described as quote "vaporware" and his integrity was not called into question with zero real hard evidence then criticism of those posts would not be valid.




One has only to look at the sig of negative responders to this post to find maybe a certain wellknown videocam - what may we deduce from this


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Atl
professor emeritus
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Reged: 04/13/12

Re: Focal Reducer for Video SCT SCopes down to F/1.5 new [Re: nytecam]
      #5914770 - 06/11/13 10:22 AM

Quote:

Quote:

Maybe if his products were not described as quote "vaporware" and his integrity was not called into question with zero real hard evidence then criticism of those posts would not be valid.




One has only to look at the sig of negative responders to this post to find maybe a certain wellknown videocam - what may we deduce from this




This is too easily noted...lol. I don't really see the issue. There is nothing wrong with supporting more than one brand of product...or allowing others free choice without rancor. I remember when I first started working with computers. You had to either like Mac, Windows, or Linux/FreeBSD operating systems. For some stupid reason I never could divine liking all three was not allowed on a public forum. If you didn't have an axe to grind participation was discouraged. I see that here. I will say that the cycling forums and the rock climbing forums (both hobbies of mine) are the worst for this. Get on a cycling forum and brag about your Walmart bike...the results will be hilarious.


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telfish
sage
*****

Reged: 11/17/10

Loc: Adirondack Mountains NY
Re: Focal Reducer for Video SCT SCopes down to F/1.5 new [Re: Atl]
      #5914792 - 06/11/13 10:37 AM

Quote:

Quote:

Quote:

Maybe if his products were not described as quote "vaporware" and his integrity was not called into question with zero real hard evidence then criticism of those posts would not be valid.




One has only to look at the sig of negative responders to this post to find maybe a certain wellknown videocam - what may we deduce from this




This is too easily noted...lol. I don't really see the issue. There is nothing wrong with supporting more than one brand of product...or allowing others free choice without rancor. I remember when I first started working with computers. You had to either like Mac, Windows, or Linux/FreeBSD operating systems. For some stupid reason I never could divine liking all three was not allowed on a public forum. If you didn't have an axe to grind participation was discouraged. I see that here. I will say that the cycling forums and the rock climbing forums (both hobbies of mine) are the worst for this. Get on a cycling forum and brag about your Walmart bike...the results will be hilarious.




I don't have a dog in this fight. I don't own a Mallincam mainly because of the over inflated price and I am not about to order any of Matt's products.

I don't however like people in essence calling him a liar and a fraudster based on zero evidence.

He is prudent not to show pictures from a prototype product.

To pass judgment on his product we will have to do what we have done with every other product. Wait for the actual production item to be available and for people to give it an independent test.

His offer to totally refund anyone who is not satisfied should reassure those who are questioning his honesty.


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Undermidnight
BEOTS "Tweener Cup" winner
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Reged: 05/25/04

Loc: Untermitternacht
Re: Focal Reducer for Video SCT SCopes down to F/1.5 new [Re: telfish]
      #5914824 - 06/11/13 10:55 AM

This thread has run its course so I am shutting it down now.

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