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Equipment Discussions >> Cats & Casses

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Sarkikos
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My First SCT: A C6!
      #5637011 - 01/22/13 02:15 PM

Last night I ordered a C6 from High Point Scientific - along with a Bobs Knobs kit - for $403. After a discount from Celestron, it was like getting the Bobs Knobs for free. I've been in this hobby for over 40 years, but I've never owned an SCT. I've owned Newts, refractors and Maks, but never an SCT. The C6 will be my first.

I had been thinking about buying a C6 for over a year now. I kept putting it off, since I already have a 150mm Mak. However, the Mak is about 4 lbs heavier and takes about 1-1/2 hours to acclimate ... if it ever really does here in "wait a minute, the weather will change" Maryland. I might decide to sell the 150mm Mak. It is a nice Rumak, but I seldom use it.

I have a 90mm Mak I usually take out for grab-n-go, but I wanted something with more aperture that would still be easy to take out and quick to setup.

I had been concerned that the price might go up on the C6 or Celestron/Synta might stop selling them. I know it wouldn't make sense to end such a popular product, but I've seen sillier things happen in this hobby. I was also hoping that maybe the price would go down. But after a year of waiting, it didn't seem like that was going to happen. So finally I pulled the trigger last night for the C6. (Now watch for a price reduction! )

I already have a mount for the C6 - my Voyager Alt-Az. Judging from threads here on CN, the Voyager seems to be a good match. I have a CG4 GEM with tracking, but IME, GEMs are not so good for grab-n-go. They are heavier, larger, more cumbersome and more complicated to setup and use than comparable alt-az mounts. If I ever feel like tracking the Moon or planets, I can bring out the CG4. But I doubt if I ever will for the C6. IMO & IME, GEMs are not optimum for true grab-n-go.

I doubt if I will order an FF/FR for the C6. I've read through several threads on this topic, and so far have decided against it. Although the off-axis field will be improved, an FF/FR will reduce the sharpness on-axis. I intend to observe a variety of objects with the C6, including planets, Moon, DSO and double stars. I don't want to bring along another accessory I need to remove/replace when I switch to different objects during the same observing session. I want to keep the setup simple for grab-n-go.

For the time being I've also decided against installing a 2" visual back and adapter. The CA of the C6 is only 27mm. I don't want to introduce vignetting into the optical system. Also, a 2" diagonal and adapter will add weight and length to the scope, and might get hung up on the mount when I'm observing near zenith. If I change my mind, I already have those gizmos that I bought for the 150mm Mak.

In fact, I might just put my Baader Hyperion Zoom in the kit when I take out the C6. To maximize low-power "wide-field," I'll include my Orion Ultrascopic 35mm. Its field stop is 28.9mm, so vignetting will be minimal.

I'll probably replace the stock 6x30 straight-through finder. I'm considering mounting my ES 8x50 finderscope instead. It's a straight-through finder with an erect-image that is non-reversed. If I use this, I won't need a Telrad/Quikfinder/Red-Dot. I can combine the functions of a Telrad and optical finder in one unit. But it remains to be seen if the weight and size are compatible with the C6. Also, the ES finder has an Antares type mount, not a Synta. So I'll have to deal with that problem.

Mike


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t.r.
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Re: My First SCT new [Re: Sarkikos]
      #5637066 - 01/22/13 02:41 PM

A lot riding on this C6! First impressions are everything afterall. But, I think you will be pleased Mike, although if your Mak was of good quality, I'm not sure how you will rate the C6 for planetary in comparison. Mine does well, it shows detail besting a fine Tak Sky 90 and a TMB 92L I had previously. I too replaced the finder with a simple red-dot reflex and the Hyperion zoom complimented the grab and go capability of the scope quite well. You will still have to wait for cool down...just put it out 30 minutes prior. Funny, I just picked up a C90 for Christmas and have swung the other way having fun with this little scope while the C6 sets idle. I can carry out either the C6 mounted on a CG4 or the C90 on an EQ-2, in one trip. So many scopes...so little time.

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Sarkikos
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Re: My First SCT new [Re: t.r.]
      #5637107 - 01/22/13 03:03 PM

Yes, I think what I really need is either more time or less scopes. My plan is to retire in a few years, so things should work out either way.

My main problem living in a condo here in red-zone suburbia, is that I need to do a bit of walking to get to any area to setup that will not completely frustrate me because of neighborhood glare or blocked skies. Up to now, my 90mm Mak on a 501HDV and tripod has been my favorite - and truest - grab-n-go scope. I think it might take me longer to find and put on all my cold weather clothes than it does to get this little scope mounted and ready to go out the door.

But as I said, I thirst for a bit more aperture, even for grab-n-go. If I can carry the C6 and a simple alt-az to some of the more favorable observing sites closeby in my neighborhood, I'll be happy.

Mike


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coutleef
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Re: My First SCT new [Re: Sarkikos]
      #5637365 - 01/22/13 05:13 PM

good luck. i have the feeling a c6 is just what you were looking for in terms of portability. i use the baader zoom with my c8 and it is a good combination in winter

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Sarkikos
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Re: My First SCT new [Re: coutleef]
      #5637419 - 01/22/13 05:37 PM

I just received an email from HPS. My C6 has shipped! HPS is in the next state over, so it should arrive very soon.

Mike


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Sarkikos
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Re: My First SCT new [Re: t.r.]
      #5637441 - 01/22/13 05:50 PM

t.r.,

Quote:

But, I think you will be pleased Mike, although if your Mak was of good quality, I'm not sure how you will rate the C6 for planetary in comparison. Mine does well, it shows detail besting a fine Tak Sky 90 and a TMB 92L I had previously.




Yes, the Mak is of good quality, but I'm seldom able to see that because it takes so long to acclimate. I don't have a deck or a yard where I can store the Mak or even set it out securely for cool-down. I could put it on my small front porch for a couple hours, but I don't really feel comfortable doing that. I doubt if anyone would pilfer it. However, it would be in the way of anyone coming in or out of the house. Not too good. This is not a good situation for scopes that require a long cool-down.

In fact, the person who sold me this 150mm Mak lived near DC, not far from here. He told me he was selling the Mak precisely because of the cool-down required!

If I do keep the 6" Mak, I'll probably only use it in the more moderate months. You might as well forget about it here in the winter. There's just too much of a change in temps from inside to outside. If I were to get another 6" or larger Mak, it better have vent holes and active cooling. Or I better relocate to a nice temperate locale ... Hawaii or the Phillipines, perhaps.


Mike


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coopman
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Re: My First SCT new [Re: Sarkikos]
      #5637606 - 01/22/13 07:37 PM

Best wishes for you & the new C6. Mine is going out tonight to look at the moon & jupiter.

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Sarkikos
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Re: My First SCT new [Re: coopman]
      #5637701 - 01/22/13 08:42 PM

Sounds like fun! Probably much more fun down there than up here. The temps have fallen into the 'teens last few nights.




Mike


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coopman
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Re: My First SCT new [Re: Sarkikos]
      #5637893 - 01/22/13 10:30 PM

Yes, it was in the 40s tonight and yet I still thought that it was cold. I'm sure that there are many here who wish that their low temp. was only in the 40s.

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Sarkikos
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Re: My First SCT new [Re: coopman]
      #5637900 - 01/22/13 10:34 PM

The 40's? That's nice daytime walking weather here. I just hope my new 6" SCT is better than my old 6" MCT at handling the low temps at night.


Mike


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azure1961p
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Re: My First SCT new [Re: Sarkikos]
      #5637989 - 01/22/13 11:17 PM

Mike one of the clinchers for me on getting a C6 was Larry Carlinos review of his saying it was every bit as good as his Synta Mak of like sized aperture. I frankly don't kno how mine compares to a like sized Mak but I can tell you when Mars was tiny the scope never failed the magnification when the sky allowed it. I really have no qualms - its a tight little scope!!!!
Much better looking than its pix too and its pix look fine.

Pete


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azure1961p
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Re: My First SCT new [Re: azure1961p]
      #5637993 - 01/22/13 11:20 PM

Oh yeah - I never found over an hour was needed in winter .
The optics are thin enough I think its more temp friendly. Between 45 and 60 min and mines good to go.

Pete


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Rick Woods
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Re: My First SCT new [Re: azure1961p]
      #5638166 - 01/23/13 01:29 AM

Ah! So you've finally given in and come over to the centrally-obstructed side!
Mwahaha!


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Sarkikos
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Re: My First SCT new [Re: Rick Woods]
      #5638317 - 01/23/13 07:06 AM

You talkin' ta me? Or Pete? Those Newts have CO's, too! It's just that the SCTs are even more centrally obstructed...

8" f/6 Newt: 19% CO
10" f/4.8 Newt: 23% CO
5" f/5 Newt: 29% CO
150mm f/12 Mak: 31% CO
150mm f/10 SCT: 37% CO?


Mike


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Sarkikos
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Re: My First SCT new [Re: Sarkikos]
      #5638418 - 01/23/13 08:45 AM

After the C6 arrives, I should do a comparo on the 6" Mak vs the 6" SCT. I could mount both scopes side-by-side on my Orion SkyView AZ. It would be a nice challenge to mix-and-match eyepieces and Barlows to achieve a fair comparison between the two on various objects. I'd hate to sell either one of them without comparing them first in the field.

The difficult part will be finding the time and opportunity. It should be a night of good seeing and transparency. And I should allow the Mak - and the SCT - enough time for a good cool-down. I really should do the comparo at my dark site, not only to have a darker sky, but for more privacy so I can take my time and focus on the comparisons. Unless, of course, that happens to be the night another astronomy club chooses to have their star party! I'll have to watch out for that.


Mike


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MRNUTTY
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Re: My First SCT new [Re: Sarkikos]
      #5639257 - 01/23/13 05:10 PM

Wow, it took you this long to get one? :-) I love mine. Is the most used scope I have. Six inch is also the most common aperture I have; SCT, Mak, and the SCT. I've been teetering on an AT6RC to complete the collection :-) ... Nah!

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Sarkikos
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Re: My First SCT new [Re: MRNUTTY]
      #5639464 - 01/23/13 07:34 PM

Yep. I've been interested in amateur astronomy since about 1970, so it took me 43 years to finally get an SCT. For the C6 specifically, I waited about a year before I pulled the trigger. This will be my last telescope acquisition for awhile.

Now I go back to DIY projects, managing a herd of eyepieces, and observing!


Mike


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azure1961p
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Re: My First SCT new [Re: Sarkikos]
      #5639558 - 01/23/13 08:55 PM

Bob don't read too too much into the large CO ON THE 6" sct. Dennis Diciccos review had revealed the actual effective aperture of the iOptron Mak was something like 143mm yielding, get this : a 41% CO!!!!! IOptron actually had the true size if their CO posted but they pulled it quick an no phone calls from me repeatedly EVER gave a value on this number. I used Dennis review and other info I sleuthed together and finally thru my hands up at the thought of 1. Ever owning a cope with a co that huge 2. Never doing business with a company so utterly evasive with the simplest factual specs requested.

Believe me Mike the CO in your sct is a non issue. I have 16% on my reflector but I adore my c6 too. It's a great performer.

I am seriously interested in your comparisons.

Pete


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aa6ww
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Re: My First SCT: A C6! new [Re: Sarkikos]
      #5639795 - 01/23/13 11:45 PM

Quote:

Last night I ordered a C6 from High Point Scientific - along with a Bobs Knobs kit - for $403. After a discount from Celestron, it was like getting the Bobs Knobs for free. I've been in this hobby for over 40 years, but I've never owned an SCT. I've owned Newts, refractors and Maks, but never an SCT. The C6 will be my first.



I had been thinking about buying a C6 for over a year now. I kept putting it off, since I already have a 150mm Mak. However, the Mak is about 4 lbs heavier and takes about 1-1/2 hours to acclimate ... if it ever really does here in "wait a minute, the weather will change" Maryland. I might decide to sell the 150mm Mak. It is a nice Rumak, but I seldom use it.

I have a 90mm Mak I usually take out for grab-n-go, but I wanted something with more aperture that would still be easy to take out and quick to setup.

I had been concerned that the price might go up on the C6 or Celestron/Synta might stop selling them. I know it wouldn't make sense to end such a popular product, but I've seen sillier things happen in this hobby. I was also hoping that maybe the price would go down. But after a year of waiting, it didn't seem like that was going to happen. So finally I pulled the trigger last night for the C6. (Now watch for a price reduction! )

I already have a mount for the C6 - my Voyager Alt-Az. Judging from threads here on CN, the Voyager seems to be a good match. I have a CG4 GEM with tracking, but IME, GEMs are not so good for grab-n-go. They are heavier, larger, more cumbersome and more complicated to setup and use than comparable alt-az mounts. If I ever feel like tracking the Moon or planets, I can bring out the CG4. But I doubt if I ever will for the C6. IMO & IME, GEMs are not optimum for true grab-n-go.

I doubt if I will order an FF/FR for the C6. I've read through several threads on this topic, and so far have decided against it. Although the off-axis field will be improved, an FF/FR will reduce the sharpness on-axis. I intend to observe a variety of objects with the C6, including planets, Moon, DSO and double stars. I don't want to bring along another accessory I need to remove/replace when I switch to different objects during the same observing session. I want to keep the setup simple for grab-n-go.

For the time being I've also decided against installing a 2" visual back and adapter. The CA of the C6 is only 27mm. I don't want to introduce vignetting into the optical system. Also, a 2" diagonal and adapter will add weight and length to the scope, and might get hung up on the mount when I'm observing near zenith. If I change my mind, I already have those gizmos that I bought for the 150mm Mak.

In fact, I might just put my Baader Hyperion Zoom in the kit when I take out the C6. To maximize low-power "wide-field," I'll include my Orion Ultrascopic 35mm. Its field stop is 28.9mm, so vignetting will be minimal.

I'll probably replace the stock 6x30 straight-through finder. I'm considering mounting my ES 8x50 finderscope instead. It's a straight-through finder with an erect-image that is non-reversed. If I use this, I won't need a Telrad/Quikfinder/Red-Dot. I can combine the functions of a Telrad and optical finder in one unit. But it remains to be seen if the weight and size are compatible with the C6. Also, the ES finder has an Antares type mount, not a Synta. So I'll have to deal with that problem.

Mike




They are nice scopes but I wouldn't use the bobs knobs on them. Those are really for Newts which need constant alignment. Most SCT's never ever need collimation since they are rock solid from the factory. Once you install the bobs knobs on them, you will always find yourself adjusting them. This is a false positive and leads people to believe these types of scopes needs bobs knobs to Collimate.
Call Celestron and talk to one of their techs. Bobs knobs are making them a fortune on collimation.
People that use them are always "chasing their tails" on collimation. People that have never had them almost always never have collimation issues, especially on the smaller scopes like your C6.
The C6 is a nice little scope. Problem with SCT's is that people get too anxious and think their scopes need collimation when they just need more time to acclimate to the outside conditions.
You will probably never need to Collimate a small SCT ever.

...Ralph

Edited by aa6ww (01/23/13 11:55 PM)


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Sarkikos
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Re: My First SCT: A C6! new [Re: aa6ww]
      #5640103 - 01/24/13 07:09 AM

Ralph,

I appreciate the concern, but I'm entering the SCT World from Newt Town. We Newtonians are pros at collimating - or we ought to be! IME, many amateurs choose an SCT as their first scope, not only because most of them come with GOTO, but because they've heard SCTs seldom need collimation ... and they've heard all the horror stories about how difficult it is to collimate a Newt. I've been collimating Newts since 1970. SCTs have only three collimation screws? Eh... Nothing to it.

But I will delay installing Bobs Knobs at least until I've had a chance to take the C6 out for a star test. I've read several threads in this forum with pro and con opinions about the Knobs. So far I'm leaning heavily toward the pro side.

I've also seen that amateurs coming from SCT World to Newt Town assume that the best and primary method of collimation is by manipulating the collimation screws during a star test. For Newts this is certainly not the case. I've never collimated a Newt by star testing. We have instruments to handle that! I reserve star testing for actually testing the optical quality of telescopes, not for collimating them. Good instruments will always give me a closer collimation than a star test. When I set up at a dark site, I collimate the Newt before the sun even sets.

A Cheshire/sight-tube followed by autocollimator are my tools of choice. I'll be looking into what tools are available to check and set collimation on SCTs. I don't like having to wait for a clear night with good seeing to collimate a telescope.


Mike


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Sarkikos
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Re: My First SCT new [Re: azure1961p]
      #5640136 - 01/24/13 07:51 AM

Pete,

Quote:

Mike one of the clinchers for me on getting a C6 was Larry Carlinos review of his saying it was every bit as good as his Synta Mak of like sized aperture.




Is this the review?

Celestron C6-S Schmidt-Cassegrainian

Mike


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Sarkikos
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Re: My First SCT new [Re: Sarkikos]
      #5640142 - 01/24/13 08:00 AM

According to Larry Carlino's article, the C6 OTA weighs in at 8.6 lbs with the finder and visual back attached. My Bosma 6" Mak OTA - with no attachments - weighs 14.4 lbs! That's nearly 6 lbs more, an increase of 67% over the weight of the C6!

Mike


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t.r.
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Re: My First SCT new [Re: Sarkikos]
      #5640205 - 01/24/13 08:53 AM

Not just weight per say...mass! Thats where the thermal issues arise. I just hope that in practice, the C6 does cool quicker for you. I'm okay with the time mine takes. Not quick look, but still grab-n-go.

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Sarkikos
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Re: My First SCT new [Re: t.r.]
      #5640276 - 01/24/13 09:44 AM

I can deal with setting the C6 out for a half-hour or so to get the cool-down going. Many times I'll do that for the 90mm Mak anyway.

Mike


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Sarkikos
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Re: My First SCT new [Re: Sarkikos]
      #5640404 - 01/24/13 10:50 AM

Here are some comments on the performance of the C6 from Larry Carlino's review.

Comparing the C6 to the Orion 150mm Mak-Cass:

Quote:

These scopes are so close in revealing lunar and planetary detail that its difficult to choose one over the other both are very good.




Comparing the C6 to a Takahashi FS-102 fluorite APO:

Quote:

A Takahashi FS-102 fluorite APO refractor showed essentially the same level of detail [on Mars], but with superior contrast and slightly less brightness at the same magnification.




On the C6's light transmission:

Quote:

By counting stars in the beautiful Double Cluster in Perseus, I was able to determine that the C6-S provided about the same light grasp as the 5-inch Takahashi APO, and ,surprisingly, almost the same as the 6-inch achromat.



Celestron C6-S Schmidt-Cassegrainian

Mike


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t.r.
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Re: My First SCT new [Re: Sarkikos]
      #5640790 - 01/24/13 02:08 PM

IME, those comments are spot on Mike. I compared the C6 to my Tak Sky 90, TMB 92L and C5 I used to own, to verify that indeed, the C6 showed more planetary/lunar detail and had much brighter images. In comparison to my old 4" Genesis, from memory, it shows the same level of detail with the nod for contrast going to the Genesis, but the C6 has the brighter image still. Now when it comes to comparing to my AP 130 GT, I can say this...I don't feel I'm missing a ton with my C6 and as my winter/grab-n-go scope, I'm very pleased with its ability to show a level of detail that satisfies much more than the 4" and 3.5" refractors and almost but not quite to the level of my 5"! The 130 still wins in contrast and brightness to my eye, but it is close enough that I can use the C6 and be satisfied when I do and not feel wanting like I did when I observed with the smaller instruments.

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RobertED
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Re: My First SCT new [Re: Rick Woods]
      #5640932 - 01/24/13 03:32 PM

Quote:

Ah! So you've finally given in and come over to the centrally-obstructed side!
Mwahaha!




...."one -of-us!, ...one-of-us!,....one-of-us!".....


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Sarkikos
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Re: My First SCT new [Re: RobertED]
      #5641297 - 01/24/13 07:19 PM

SCT Freaks!

Mike


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mattyfatz
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Re: My First SCT new [Re: Sarkikos]
      #5642359 - 01/25/13 11:17 AM

"They are nice scopes but I wouldn't use the bobs knobs on them. Those are really for Newts which need constant alignment. Most SCT's never ever need collimation since they are rock solid from the factory. Once you install the bobs knobs on them, you will always find yourself adjusting them. This is a false positive and leads people to believe these types of scopes needs bobs knobs to Collimate. "

2nd


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coopman
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Re: My First SCT new [Re: mattyfatz]
      #5642381 - 01/25/13 11:28 AM

I have them on my newt, but I'm scared to try & put them on my C6. If it ain't broke, don't fix it.

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BigC
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Re: My First SCT new [Re: Sarkikos]
      #5642384 - 01/25/13 11:30 AM

The comparison results and comments are not surprising considering the three .

I would expect scopes of equal effective aperture and decent optics to have near-identical results.


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Sarkikos
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Re: My First SCT new [Re: BigC]
      #5642545 - 01/25/13 01:03 PM

The C6 arrived today in good condition. It should have been left at my house two days ago, but we had to do a dance with UPS because HPS required a signature. To make a long story short, I went ahead and took a day off today to accept delivery. Anyway, it's Friday, and they were calling for snow. Win-win-win.

I checked the corrector, the primary, and the general condition of the scope. Everything looks great. No corrector sleeks, no scratches or fingerprints on the primary, the visual back is easy to screw off and on.

The C6 is surprisingly light. It doesn't seem any heavier than my ST80 with 2" Crayford! Compared to my 6" Mak, the C6 is like an empty paint can while the Mak is full of paint! These Cats always seem like paint cans or buckets to me. The C6 should be easy for grab-n-go. Not as easy as my little 90mm Mak, but probably easier than the ST80, and certainly easier than the 6" Mak.

Mike


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Sarkikos
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Re: My First SCT new [Re: Sarkikos]
      #5642567 - 01/25/13 01:13 PM

If the sky is clear and the seeing is OK tonight - it hasn't snowed yet - I might set up the C6 on my porch and check the optics and collimation by sighting Polaris.

It's a shame that the standard way to collimate these SCTs appears to be star testing. That's not really a very efficient way to go about it. I can collimate my Dobs and refractors anytime I want without leaving the house. I don't need to wait for a clear night and good seeing. I don't need to lug the Dob or refractor outside to collimate. If I do take them out to collimate, it's actually easier during the day than the night. And I don't have to take up precious time collimating on a night of good seeing.

Mike


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Re: My First SCT new [Re: Sarkikos]
      #5642594 - 01/25/13 01:27 PM

About Bob's Knobs ...

Seems like I've stirred up a hornet's nest by mentioning this topic. Judging from threads here in the Cats & Casses Forum, Bob's Knobs have been an ongoing controversy for awhile now.

I've put Bob's Knobs on all my Newts. For Newts, the Knobs make collimation MUCH easier and for me at least, make it easier to get a tight, secure collimation on the secondary. Many times I'll collimate with the Knobs here at home before travelling the 50 miles to my dark site. Most of the time the collimation is still tight when I get there. No problem at all.

My C6 has little Phillips collimation screws on the secondary. From my experience collimating Newts, I do not like using a Phillips screwdriver or allen wrench to adjust the secondary collimation. Even though I always collimate with the OTA horizontal, so the tool won't fall down onto the primary, I still worry about dropping it on the secondary.

At any rate, collimating with a tool is awkward. Bob's Knobs are much, much easier to use. I don't need a tool other than my fingers to turn them! For my smaller Newts, I can look in the Cheshire or autocollimator while I'm turning the Knobs. That makes collimation so easy it's almost a pleasure ... almost.

As far as Bob's Knobs not being tight enough or too tight on the SCT secondary, I think that would be mostly due to operator error. There is such a thing as "snug tight," folks.

But I'm in no hurry to install the Knobs. I'll check the factory collimation first.

One big point in Bob's Knobs favor is that Uncle Rod likes them!


Mike


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rguasto
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Re: My First SCT new [Re: Sarkikos]
      #5642650 - 01/25/13 01:55 PM

I don't think you need bobs knobs. The collimation screws have very little tension to them so striping the philips heads will not happen. In 2 years I have collimated my C6 2 times and each time collimation was off very little (and I star testevery time I observe). I can guarantee that if you replace the screws it WILL need to be collimated. As far as cool down time is concerned - images do not stabilize (in my experience) for close to 90 minutes. I have left it outside for 2 hours with the cover on and then put the dew shield on and discovered that it still needed to cool even more. Cool down times are faster with the corrector plate exposed. I use a surgical hair cap to cover the dew shield while the scope is cooling unattended. It's like a shower cap, but allows air in while keeping the corrector plate clean from dust and air-borne debris. Oh yeah; in cold weather the cover does not fit tightly when you pack-up for the night - in fact it will fall right off. I placed adhesive felt next to the tabs to remedy this.
-Rob


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Sarkikos
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Re: My First SCT new [Re: rguasto]
      #5642736 - 01/25/13 02:47 PM

Rob,

Quote:

I don't think you need bobs knobs. The collimation screws have very little tension to them so striping the philips heads will not happen. In 2 years I have collimated my C6 2 times and each time collimation was off very little (and I star testevery time I observe). I can guarantee that if you replace the screws it WILL need to be collimated.




No, I don't need Bobs Knobs. I didn't need them for my Newts, either. But they would make it easier - and safer - to collimate the SCT, as it does for my Newts. I fully expect the collimation to be off once I install the Knobs. Most of my experience has been with Newts. Collimation is not a big deal for me.

Mike


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Re: My First SCT new [Re: rguasto]
      #5642743 - 01/25/13 02:52 PM

Rob,

Quote:

Cool down times are faster with the corrector plate exposed. I use a surgical hair cap to cover the dew shield while the scope is cooling unattended. It's like a shower cap, but allows air in while keeping the corrector plate clean from dust and air-borne debris.




Yes, I was concerned about leaving the corrector plate exposed for cool-down, but it does make sense to do that. Where can I get a surgical hair cap to fit my C6? ... I mean, besides going to a hospital and asking around for one. I don't do that kind of thing.

Quote:

Oh yeah; in cold weather the cover does not fit tightly when you pack-up for the night - in fact it will fall right off. I placed adhesive felt next to the tabs to remedy this.




I'd be concerned about the adhesive coming undone and ending up on the corrector plate. We have a lot of dew in my area. But thanks for the heads up about the loose cover.

Mike


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Sarkikos
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Re: My First SCT new [Re: Sarkikos]
      #5642910 - 01/25/13 04:20 PM

It's snowing. I don't think I'll get a chance to check the scope's collimation tonight.

Mike


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Re: My First SCT new [Re: Sarkikos]
      #5644559 - 01/26/13 02:57 PM

It's not convenient to place a Christmas bulb in a tree and collimate off that during the day. I live in a condo and do not have a backyard. Neighbors might find it odd to see a middle-aged man shimmy up a tree in the common area to put up a Christmas ornament.

I looked around for a glinty object that I could point the C6 at from my house. First I tried the shiny edge of a metal exhaust vent pipe on a roof in the court behind me. Then I tried the glint off the fender of a car. I used a BGO 18 (83x, 14x/inch), BGO 7 (214x, 36x/inch), BGO 6 (250x, 42x/inch) and XO 5.1 (294x, 49x/inch). The shadow of the secondary appeared concentric at all these magnifications, and the image seemed the same on both sides of focus.

This was enough to let me know that my C6 is at least reasonably well collimated. Maybe neither glint was small enough or the sun wasn't bright enough or both, but I couldn't get a good view of diffraction rings for a thorough test.

Mike


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Re: My First SCT new [Re: Sarkikos]
      #5644667 - 01/26/13 04:17 PM

Glad that you got your new scope OK, Mike. The C6 is so lightweight that many who handle it might think that it feels more like a toy and not a decent quality telescope. I still wish that they'd put some sort of handle on these things for the times when you're putting it on and off the mount. I'm always afraid that I'm going to drop it.

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azure1961p
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Re: My First SCT new [Re: coopman]
      #5644833 - 01/26/13 06:03 PM

Mike,

So glad it arrived intact and healthy. I've never needed 90minutes in the c6 cooling but that's my locale anyway. I'd high recommend blowing a fan on the OTA as its cooling. Typical isolating fan kept stationary blowing on it ought to do fine. I'm virtually positive this set up would get you up and ready in under an hour even in winter.

I've never entertained the bobs knobs idea . The little scope holds collimation really well so the few times I've tweaked it was you kno - shrug and forget. I like the idea of not needing a Phillips tho.

With regard to my c6 I've got a challenge I've kinda set for myself. I've resolved Titan visually with my 8" and theory sais the 6" can do it too. Alas its kinda faint at the mags needed so in hoping I can image a resolved disc and share it here on CN. The DBK can offset the brightness issues with a little gain I'm guessing.

I'm looking forward to hearing great things about your 6".


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azure1961p
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Re: My First SCT new [Re: Sarkikos]
      #5644858 - 01/26/13 06:23 PM

Quote:

Pete,

Quote:

Mike one of the clinchers for me on getting a C6 was Larry Carlinos review of his saying it was every bit as good as his Synta Mak of like sized aperture.




Is this the review?

Celestron C6-S Schmidt-Cassegrainian

Mike




Yup that's the one!

Pete


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t.r.
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Re: My First SCT new [Re: azure1961p]
      #5645604 - 01/27/13 08:27 AM

That's it guys...push the C6 to its limits!!!

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EdZ
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Re: My First SCT new [Re: t.r.]
      #5645675 - 01/27/13 09:31 AM

Info you should know about the C6, or any small SCT for that matter.

They were not designed to add a lot of length in accesories off the back end. Tthe shorter you keeep it the better off you are.

f/10 is only nominal and occurs at only ONE single position. Your scope is almost never operating at f/10.

These scopes were not made for use like you see in some photos here on CN, with 2" diagonals, reducers and binoviewers. Put a reducer, a 2" diagonal and a binoviewer on the back end of a 6" SCT and it'll be operating close to 4".

Best used with a 1.25" diagonal (or a short 2" diagonal) too get the full aperture.

With a standard 1.25" visual back and a standard 1.25" mirror diagonal, a C6 is operating near F=1700.

Operating Focal Length of C6

For info on operating aeprture in various configurations read the entire thread
Aperture of C6 in varrious configurations

I like my C6, I simply respect how it was made to operate and do so within those confines.

edz


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Sarkikos
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Re: My First SCT new [Re: EdZ]
      #5645820 - 01/27/13 11:00 AM

Edz,

Quote:

Info you should know about the C6, or any small SCT for that matter.

They were not designed to add a lot of length in accesories off the back end. Tthe shorter you keeep it the better off you are.

f/10 is only nominal and occurs at only ONE single position. Your scope is almost never operating at f/10.

These scopes were not made for use like you see in some photos here on CN, with 2" diagonals, reducers and binoviewers. Put a reducer, a 2" diagonal and a binoviewer on the back end of a 6" SCT and it'll be operating close to 4".

Best used with a 1.25" diagonal (or a short 2" diagonal) too get the full aperture.

With a standard 1.25" visual back and a standard 1.25" mirror diagonal, a C6 is operating near F=1700.




After researching the reducers and FF/FC's here on CN and elsewhere, I've decided not to buy one. (I did have a couple reducers, but I sold them.) They might be helpful for AP, but I'm stictly a visual observer. I have absolutely zero interest in AP.

Also, I have no desire to stretch the FOV of the SCT. My C6 as is with my Ultrascopic 35 should give me a little over 1 degree AFOV, 43x and 3.5mm exit pupil. That will serve me well enough here in red zone suburbia. I have a 5" f/5 Dob, 25x100 binos and an ST80 for rich field/wide field at my dark site. Even my 10" f/4.8 Dob will give me 30x and 2.2 degrees with a Titan-II 40mm. The ES 82 30 in the 10" will yield about 40x and 2 degrees at a comfortable (for me) exit pupil of 6.3mm. So I have no need to over-max the TFOV in my C6.

Mike


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Re: My First SCT new [Re: EdZ]
      #5645918 - 01/27/13 11:55 AM

Edz,

I was considering using my C6 with my Burgess binoviewer for Moon and planets (I don't binoview DSO). Since reading your thread, I'm thinking twice about that. I want to binoview with a 2" diagonal for a secure connection. But I don't want to reduce the C6's effective aperture to 5". I think I'd rather observe the Moon and planets monoviewed with a 6" than binoviewed with a 5".

This sentence from the first post in your thread was a clincher for me:

Quote:

What this shows is there does not seem to be any binoviewer configuration that gives full aperture. And frankly, I would not use my BV on the back end in a 1.25" diagonal. So, just about any BV configuration I select would result in a loss of at least 14 to 18mm in aperture.




I think I'll continue to binoview with my 8" and 10" Dobs only.

Mike


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aa6ww
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Re: My First SCT new [Re: Sarkikos]
      #5646403 - 01/27/13 04:40 PM

I wonder how long it will be before this shows up on the used market with stripped out secondary screws, and uneven aftermarket focuser, internal fans installed, the rear cell threads stripped out, mirror locks and a the corrector reinstalled incorrectly. I say 6 months tops!! Your killing me Mike.

...Ralph

Edited by aa6ww (01/27/13 04:44 PM)


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azure1961p
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Re: My First SCT new [Re: aa6ww]
      #5646617 - 01/27/13 06:26 PM

I think in some applications the loss of aperture for binoviewing is negligible - I'm guessing as I haven't done it yet. Terrestrial spotting would be fine and I'm gonna leap here and say the comfort and efficiency of bino viewing offsets the aperture loss on contrasts on lunar and planetary.

I'm interested in a lot of your results now Mike !

Pete


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orion61

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Re: My First SCT new [Re: azure1961p]
      #5646650 - 01/27/13 06:38 PM

you are going to love the C6! they are surprisingly good for the money, and I dont care what anybody says, They give their big Brother 8" a HECK OF a run for the money on Planetary!
As a matter of fact with my Midwest skys I think the 6" out performs it on many nights!!
ENJOY, ENJOY, ENJOY!!! They are the best scope Celestron
has come out with since the 11 and 14!


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Sarkikos
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Re: My First SCT new [Re: aa6ww]
      #5646877 - 01/27/13 08:31 PM

Quote:

I wonder how long it will be before this shows up on the used market with stripped out secondary screws, and uneven aftermarket focuser, internal fans installed, the rear cell threads stripped out, mirror locks and a the corrector reinstalled incorrectly. I say 6 months tops!! Your killing me Mike.

...Ralph




Not gonna happen', Ralphie Boy.

Festina lente is my motto.

Mike


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Sarkikos
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Re: My First SCT new [Re: azure1961p]
      #5646909 - 01/27/13 08:47 PM

Pete,

Quote:

I think in some applications the loss of aperture for binoviewing is negligible - I'm guessing as I haven't done it yet. Terrestrial spotting would be fine and I'm gonna leap here and say the comfort and efficiency of bino viewing offsets the aperture loss on contrasts on lunar and planetary.

I'm interested in a lot of your results now Mike !

Pete




Well, if the effective aperture of the C6 is reduced to 5" with the binoviewer, you still have the equivalent of a 5" binoviewed. That's not so bad. Even so the C6 plus binoviewer will be easier to take out than a 5" refractor. Of course, if I'm binoviewing I'd much rather have a setup where I can use the entire aperture of the C6 - or most of it.

At the end of his tread, Edz appears to concede that this is possible with the C6, but only after much thought and probably more money. I'd rather do the research first before I put out the money. Ideally, I want to binoview with the Burgess binoviewer I already have, and just purchase the adapter and diagonal to make it possible to use most or all of the C6's aperture. I don't want to buy another binoviewer now. If that's not possible, I'll just monoview. No biggie.

Mike


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Sarkikos
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Re: My First SCT new [Re: Sarkikos]
      #5655955 - 02/01/13 09:47 AM

Yesterday I removed the 6x30 finder and bracket from my C6. I replaced it with an ES 8x50 straight-through illuminated finder. This finder is straight-through, erect-image and non-reversed, so the orientation will match the naked-eye view as well as most any atlas I use.

The bracket for the ES finder has four screws for attachment. The supplied screws were too short for the C6, so I had to find some among my old telescope hardware. Unfortunately, the C6 only has two screw holes for mounting a finder. Well, actually there are two pairs of the holes, one pair on each side of the focuser.

I attached the ES bracket to the C6 OTA with two screws. This seems to be secure and stable enough. I held the C6 with attached ES finder in various positions, moved the OTA around, and the connection appeared secure.

Mike


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Re: My First SCT new [Re: Sarkikos]
      #5657544 - 02/02/13 03:13 AM

Mike,
Have you actually used the scope yet? If not, you might want to hold off customizing it until you're sure it's a good one.


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t.r.
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Re: My First SCT new [Re: Rick Woods]
      #5657711 - 02/02/13 08:49 AM

Even if it isn't, send it back for a replacement...it is worth exchanging until you get a good one...I did!

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Re: My First SCT new [Re: Rick Woods]
      #5657750 - 02/02/13 09:19 AM

Rick,

Quote:

Have you actually used the scope yet? If not, you might want to hold off customizing it until you're sure it's a good one.




No, not yet. It seems that winter weather has come upon us since the C6 was delivered. I need to carry the scope around the side of my building to setup. That's not going to happen while there's snow and ice on the ground. But I might just put it on the porch and test it on Polaris.

Despite what Ralphie Boy said, I'm in no hurry to customize this scope. Besides, I want to see how it performs from the baseline first. The only change I've made is to replace the 6x30 with an ES 8x50 finder, but I can put the old finder back on if I decide to return the scope.

I don't now what non-reversible changes I could make except for maybe flocking the baffle and the interior of the OTA. I'm in no hurry to do that.

I've never returned a scope. Luckily, mine have all been fine so far. Not "excellent" perhaps, but at least decent. I'm not the type who orders a scope, and keeps returning and replacing them until I hit the Chinese scope lottery. Yes, if the scope is clearly a lemon, I will return it.

Winter is not a good time for excellent seeing here - to put it mildly - so I don't know when I'll be able to do a thorough star test. But the daytime collimation check seemed right on. No significant difference on either side of focus.

Mike


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Sarkikos
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Re: My First SCT new [Re: t.r.]
      #5657755 - 02/02/13 09:22 AM

t.r.,

Quote:

Even if it isn't, send it back for a replacement...it is worth exchanging until you get a good one...I did!




How many times did you exchange your C6 until you got an acceptable one?

Mike


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t.r.
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Re: My First SCT new [Re: Sarkikos]
      #5657901 - 02/02/13 10:55 AM

Oh, just once. The first one I had didn't have equal star test image on either side of focus. Even the the planetary performance seemed just okay, the defocused diffraction pattern told me something was amiss. The first one was the "newer" model, with the nicer dew cap(formed handle in the plastic) with a nicer tube finish and stenciled logo. The second one was the older tab dew cap, duller surface paint and a stickered logo, I kid you not! But when I star tested it and put it on Jupiter, I knew this "Ugly Duckling" was a keeper. I later took it to "Barefoot" Bob Piekel(SCT guru) for testing just to confirm I wasn't imagining its performance. He tested it to close to 1/8 wave slightly overcorrected (1/6 to 1/7th solid)! He said the C6's he has tested have been consistently very good. My first was simply not up to my expectations, it happens. Work with the dealer and exchange...it was painless.

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Sarkikos
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Re: My First SCT new [Re: t.r.]
      #5658027 - 02/02/13 12:13 PM

So it seems like your first was a lemon, worse than the usual C6 that comes off the line.

My C6 has a shiny black surface - no sparkly effects, though. "Celestron" is stenciled in orange, and there's a sticker that says "Star Bright XLT." The dew cap has tabs.

The vendor exchanged your newer model for an older one?

Mike


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t.r.
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Re: My First SCT new [Re: Sarkikos]
      #5658110 - 02/02/13 01:01 PM

I believe this to be the case, it was during the change over with the C6, so they probably had stock of both. IIRC the packaging was the same. I liked the newer lens cover better.

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Sarkikos
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Re: My First SCT new [Re: t.r.]
      #5658117 - 02/02/13 01:05 PM

I have a Hubble artificial star that I'll use to test the C6 here in my house, if I can find a line of sight that's long enough to get a half-way decent test. The star is rigged up on a photo tripod, and the C6 is on a Voyager mount. Seems like these artificial stars might be close to useless unless you have a huge house or a back yard with enough space for a good test.
Condo astronomy is a royal PITA!

I ought to move to wild wonderful West Virginia! Yahoo! Plenty of space down here - not just what's up there in the wild black yonder!

Mike


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t.r.
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Re: My First SCT new [Re: Sarkikos]
      #5658144 - 02/02/13 01:23 PM

The telephone pole glass insulators work very well when its sunny! In addition you can try a silver christmas tree ornament...it actually works too!

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Sarkikos
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Re: My First SCT new [Re: t.r.]
      #5658346 - 02/02/13 03:21 PM

No above ground telephone poles in my neighborhood. All the trees are in common areas. Not my property. It would not look too good to see a middle-aged man shimmy up a tree to hang a Christmas ornament.

Things are different in Condo World. You really need to think out of the box.

What I might do is set up the artificial star on the front porch. Then I can walk the C6 outside to the back corner of our building, or maybe farther away, sight on the star and check the scope.

Mike


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Re: My First SCT new [Re: Sarkikos]
      #5658841 - 02/02/13 08:10 PM

Today I set up the artificial star in my home, as far as possible from the C6. I put my BCO 10mm in the focuser, for 150x, 1x per mm of aperture (p. 17, Star Testing). Of course, since the distance was much less than the minimum 49' suggested by Suiter (p. 91), this resulted in some induced spherical aberration in the defocused star image. Actually, Suiter recommends two to three times this distance, about 100' to 150'.

Other than this SA which was an artifact of the imperfect test conditions, everything looked alright. The image looked smooth, no roughness at all. No obvious zonal problems. The image did look about SA = 1/3 wave, comparing to pictures on p. 193 of Suiter's book. But how much of this was due to having the artificial star about 1/5 of the recommended distance from my C6?

I thought there might be a little astigmatism. Or could the horizontal position of the OTA produce some astigmatism? But I checked this by turning my head. Yep, the angle of elongation turned with my head. After that, I kept my glasses on.

Collimation looked perfect. (I even checked that with my XO 2.5mm, giving 600x, 100x per inch.) I'm in no hurry to replace the little Phillip's head screws with Bob's Knobs.

Unfortunately, it snowed again this evening, and winds gusts are up to 30 mph. So there is no way I should even do an artifical star test outside tonight.

Mike


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azure1961p
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Re: My First SCT new [Re: Sarkikos]
      #5659032 - 02/02/13 10:30 PM

Mike ,

Im glad to hear about your star test success. I would gamble strongly the 1/5 distance had a good measure to do with the SA. Im not really star test savy like Eddgie, Norme or some of the other guys. I look for clear stark diffraction patterns, astigmatism and then call it a day. I too have a little astigmatism that is problematic at the lower end power oculars. In the 8" im great withy 20mm oculars or smaller. I keep proising myself that astigmatism corrector that Televe makes but as if yet I havent bothered. Does away with the need for glasses by essentially mounting one to your ocular. They DO have astigmatism corrected contacts but in my experience they reduce contrast and some sharpness as they tend to dry out when you observe.

I know you are going to be so happy with the C6 - and the light transmission is terrific. Doesnt that secondary look like its floating in mid air at times?

The XLT coatings are no joke!!

Pete
Mike you observe from your condo too? It took my years to do this as I hated the lack of privacy. I still get interuptions and on summer night weekends its a nogo as too many back deck partiers and such intrude. Hence I drive to a provate place those times - or grumble and stay in the house.

Edited by azure1961p (02/02/13 10:33 PM)


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Sarkikos
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Re: My First SCT new [Re: azure1961p]
      #5659883 - 02/03/13 12:18 PM

Pete,

Quote:

Im glad to hear about your star test success. I would gamble strongly the 1/5 distance had a good measure to do with the SA. Im not really star test savy like Eddgie, Norme or some of the other guys.




Yes, so far so good. I will have to set up the artificial star on my porch, and my C6 about 150' away to get a decent test. I hope I have a clear line of sight here in congested Condo World. Everything looked good except for that SA. My estimate of 1/3 wave was completely based on the SA, which I expected due to the pitifully truncated test distance.

However, the prediction is for snow showers every night until Wednesday. Don't you just love winter astronomy? NO!!!!

So the next clear night for a test with Polaris will be this Wednesday, also. Luckily I have a clear view of the North Star from my porch. I hope glare from the neighbor's lights won't affect the test. Scotophobes!

Winter in Condo World - my definition of Hell for amateur astronomers.

Mike


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azure1961p
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Re: My First SCT new [Re: Sarkikos]
      #5660019 - 02/03/13 01:40 PM

Well whats great about winter in condo world is a lot of folks are in with the doors shut and no porch peepers checking in on your business. I find I really really treasure the solitude of the pursuit. I consider fellow amateurs part of that solitude but when I have to do the twenty questions with passerbys and my fav : How much did this cost?" Im really wishing I lived in the country again.

The seeing is whats really lousy about winter. When I did live in the country, often poor seeing had great transparency and so deep sky was on the menu, moon willing. But when my moon-free sky is magnitude 5 its hard flr me to take any deepsky serious at all and so poor seeing just kinda sets the tone.

Im betting those unbearable heatwaves of summer bring you steady seeing though much as it does up here in CT. Then the transparency takes a hit but in mag 5 skys its a shrug.

I wonder if I wouldve taken mag 5 skys more serious had I not had 6.2v skys for so many years first.

Didnt mean to sidetrack - back to the thread focus.

Pete


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BigC
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Re: My First SCT new [Re: t.r.]
      #5661044 - 02/04/13 01:26 AM

Quote:

The telephone pole glass insulators work very well when its sunny! In addition you can try a silver christmas tree ornament...it actually works too!


Now that is something I need to do;if I can just get the ornament well up in the tree!

Local hunters will probably think some crazed bird ,raccoon, or squirrel carried it into the branches.


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aa6ww
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Re: My First SCT new [Re: azure1961p]
      #5661060 - 02/04/13 01:47 AM

I think the C6 is one of the nicest true "Grab and Go" scopes out there. It really doesn't require any noticeable cool down time because the optics are always rock solid sharp and its so small it sets up nice on a small mount like my Vixen StarGuy Alt Az Pro Telescope Mount literally in seconds. Its got plenty of aperture for a few hrs of fun, or an entire night out, and the size is such that its forgiving to the atmospheric conditions vs even a C8 because it doesn't have to punch such a large hole in the sky to be effective. I have an orange tube C6se and its perfect with a 24pan up to about 175x just about every night with my 1.25" TV diagonal and the StarGuy alt az mount. It also makes a nice quick set up solar scope when I wanna catch the sun during my lunch hr at work.

...Ralph


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Sarkikos
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Re: My First SCT new [Re: azure1961p]
      #5661227 - 02/04/13 07:28 AM

Pete,

Quote:

Well whats great about winter in condo world is a lot of folks are in with the doors shut and no porch peepers checking in on your business. I find I really really treasure the solitude of the pursuit.




Yes, that is the one good thing about winter here.

Quote:

I consider fellow amateurs part of that solitude but when I have to do the twenty questions with passerbys and my fav : How much did this cost?"




I always give a low-ball figure. Don't want to tempt them. You never know. But here most passersby just pass by. It's amusing how many give a startled little gasp or jump when they see me sitting outside at night. They're more afraid of me than I ever would be of them. Ha! Ha! Scotophobes!

Quote:

Im betting those unbearable heatwaves of summer bring you steady seeing though much as it does up here in CT. Then the transparency takes a hit but in mag 5 skys its a shrug.




I have no trouble with the heat or mosquitoes. Better for me than snow, ice, cold and wind. There are periods of excellent seeing in the summer and fall. The rest of the year is usually mediocre to poor.

Quote:

Didnt mean to sidetrack - back to the thread focus.




A separate thread on problems and solutions for condo/apartment astronomy is in order. I might start one in the General Observing Forum.

Mike


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Re: My First SCT new [Re: Sarkikos]
      #5666195 - 02/06/13 10:51 PM

I took out my C6 for a star test this evening. According to CSC, the seeing and transparency were average. I thought the seeing was somewhat better than this, maybe 7/10. I let the scope sit out on my porch for a full hour to acclimate. Then I sighted on Polaris for a star test.

I used three eyepieces in succession for the test: BCO 10 for 150x and 1.0mm exit pupil; XO 5.1 for 294x and 0.5mm exit pupil; XO 2.5 for 600x and 0.3mm exit pupil. As I saw with the artificial star when I was testing in my house, the collimation was right on. For each eyepiece, I tried to set the focuser at about 5 and 10 wavelengths inside and outside focus. I could see no appreciable difference at any setting on either side of focus for any of these three eyepieces. No SA at all as far as I could see.

I'm not an expert on star testing, but I made a careful attempt to approximate the wavelength settings as shown in Star Testing. As a double-check, I tried to make sure that for each setting, I was comparing patterns of approximately the same size on each side of focus.

I also noticed that there did not seem to be any mirror shift or focus slip at all on the C6, no matter which way I turned the focus knob! Now, this was a very pleasant surprise after my experience with both of these aggravations on my 90mm Mak. And the temps were in the '20's. The little Mak always has these troubles when it gets that cold outside. But not the C6! In this way it's more like my 6" Mak, which also has rock steady focus.

So I don't think I'll be sending the C6 back for an exchange or refund! I'm satisfied that this scope has at least decent optics, perhaps very good. Is it 1/8 wave? I don't have the expertise to certify that, but it looked pretty good to me.


Mike


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Re: My First SCT new [Re: Sarkikos]
      #5666224 - 02/06/13 11:12 PM

Since the seeing was decent and the C6 checked out AOK, I thought I ought to carry it around the side of my building for a first light. I was a little surprised that I could carry it down a flight of half-a-dozen steps on my porch, while the OTA was mounted on the Voyager Alt-Az. No problem. This is going to be a great grab-n-go scope!

My first object was Jupiter. I viewed it with the BCO 10 at 150x, then the XO 5.1 at 294x. I could see up to about six bands, the polar regions, and some mottling and uneven edges on the NEB and SEB during moments of steadier seeing. This was an unfiltered view. I'm used to observing Jupiter with a Moon & Sky Glow filter. I bet with the filter I could tease out some more detail.

Three moons were visible. All of them appeared as definite disks, little worlds. I could tell that the one on the east was Ganymede. The disk was obviously larger. Unfortunately, the GRS was not on the visible side of Jupiter while I was outside with the C6.

Next I looked at Sirius. Could I see the Pup? No, not tonight. Maybe on a better night. While I was there, I viewed M41 with an Ultrascopic 35 (43x, 1.1 degrees TFOV, 3.5mm exit pupil). The cluster was nicely framed. The stars looked very nearly sharp across the field. I only needed to focus about half-way between on-axis and edge of field to make all the stars appear nearly pin-points. There must not be much FC or other field aberrations for me to be able to do that. And I'm very sensitive to FC.

I turned to M42. With the XO 5.1 in the focuser for 294x, I could see the E and F stars. E was visible nearly all the time. I could see F for over half the time. The BCO 10 at 150x still showed the E star fairly consistently, but F was only glimpsed now and then.

Not a bad first light for this C6! I think I'll keep it!


Mike


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azure1961p
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Re: My First SCT new [Re: Sarkikos]
      #5666574 - 02/07/13 07:30 AM

Mike -

This is so good to read - not surprised its a performer for you too, but glad just the same. Now the real showdown Im looking for is a dedicated 6" Celestron versus the 6" iOptron Mak.

That's gonna be good!


Pete


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Re: My First SCT new [Re: azure1961p]
      #5666580 - 02/07/13 07:36 AM

Very good news Mike. Enjoy that little gem. Make sure you have a Telrad on it!

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Re: My First SCT new [Re: bilgebay]
      #5666603 - 02/07/13 08:04 AM

Jeez Mike...you've already surpassed my C6 Jupiter observations with 294x! The best I have attained so far is around 175-200x. If you got that out of it and liked the image, I have no doubt it's in the 1/8th range. I think you can breathe easy and Enjoy!

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Re: My First SCT new [Re: azure1961p]
      #5666639 - 02/07/13 08:39 AM

Pete,

Quote:

This is so good to read - not surprised its a performer for you too, but glad just the same. Now the real showdown Im looking for is a dedicated 6" Celestron versus the 6" iOptron Mak.

That's gonna be good!




Yes, I was sweating bullets worrying if I would have the opportunity to do a star test on the C6 before the time expired in which I could return it. The seeing is usually pretty poor here in winter. I guess that's something we should consider before we order a scope this time of year! If the seeing hadn't been steady last night, I was going to set up the artificial star. I'm happy now that I know the collimation is dead on and the optics are at least 1/4 wave, and probably a lot better than that.

I don't know when I'll get to do a comparo between the C6 and my 6" Mak. This weekend I'm taking my 10" to a dark site. I ought to take the two Cats there sometime for a good comparo, but not this New Moon. I could do it here by the house, but I actually feel more relaxed and can do more when I'm in that field in the middle of the woods at the dark site.

The Mak's not an iOptron, but a Bosma f/12 Rumak. Judging from previous views of the star pattern in the Mak, it is at least diffraction limited. I ought to do another star test on that scope, too.

Mike


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Re: My First SCT new [Re: bilgebay]
      #5666641 - 02/07/13 08:42 AM

Sedat,

Quote:

Very good news Mike. Enjoy that little gem. Make sure you have a Telrad on it!




I'll enjoy the C6 ... but that OTA will be a Telrad-free zone!


Mike


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Re: My First SCT new [Re: t.r.]
      #5666650 - 02/07/13 08:50 AM

t.r.,

Quote:

Jeez Mike...you've already surpassed my C6 Jupiter observations with 294x! The best I have attained so far is around 175-200x. If you got that out of it and liked the image, I have no doubt it's in the 1/8th range. I think you can breathe easy and Enjoy!




We can always pump up the power, but will the image handle it well? At 294x, the image was starting to show a bit of that typical "Jupiter doesn't like high power" fuzziness around the edges, but it wasn't really bad at all. I could tell that if the seeing were a little better, and maybe I slipped on an M&SG filter, I'd be able to tease out some fine detail, maybe comparable to what I see in my 8" f/6 Dob. Even last night at 7/10 seeing, I'm confident that if I'd concentrated just on Jupiter and waited for moments of better seeing, I could have pulled out some more detail from that image.

But remember, too, that I was looking at Jupiter through an XO 5.1! That might have had something to do with it.


Mike


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aa6ww
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Re: My First SCT new [Re: Sarkikos]
      #5666686 - 02/07/13 09:22 AM

Quote:

t.r.,

Quote:

Jeez Mike...you've already surpassed my C6 Jupiter observations with 294x! The best I have attained so far is around 175-200x. If you got that out of it and liked the image, I have no doubt it's in the 1/8th range. I think you can breathe easy and Enjoy!




We can always pump up the power, but will the image handle it well? At 294x, the image was starting to show a bit of that typical "Jupiter doesn't like high power" fuzziness around the edges, but it wasn't really bad at all. I could tell that if the seeing were a little better, and maybe I slipped on an M&SG filter, I'd be able to tease out some fine detail, maybe comparable to what I see in my 8" f/6 Dob. Even last night at 7/10 seeing, I'm confident that if I'd concentrated just on Jupiter and waited for moments of better seeing, I could have pulled out some more detail from that image.

But remember, too, that I was looking at Jupiter through an XO 5.1! That might have had something to do with it.


Mike




Great news on your optics mike. My little orange tube C6 is also razor sharp with no detectable image shift in the focuser. You inspired me to take mine out last night because the seeing was near perfect last night here in calif, being listed at 4/5 from the CSC anyways. I watched the GRS transit jupiter last night from about 9pm to 11pm on my patio which faces south. I was able to get about 165x consistantly with my 9 nagler for the entire duration of the transit. Plenty of details were showing up on the big gas planet. Occassionally I was able to slip in my 7 nagler for about 214x ( I think) but that was too much magnification most of the time and softened up the details so much the GRS was difficult to detect. I was even tempted to slip in my denkmeiers to try them out but maybe another night. This was really the first time I used the scope on my GP-DX mount, what a nice combination there two are. I also took a look at the sombrero galaxy in corvus along with the asterisms jaws and the stargate, all three were excellent views. I also looked at m66 and m67 in leo, trying to see all three of the leo triplets but had to use advert vision to see the third ngc galaxy. Pretty fun with the little scope, only taking 5 minutes to set up. Fri and sat are showing clear skies here, I think I'll dig into some deep space with the C6 then, on this mount. The telrad is a must by the way for star hoping and getting your bearing on the deep space objects you cant see naked eye. Thanks for the inspiration.

...Ralph


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t.r.
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Re: My First SCT new [Re: aa6ww]
      #5666954 - 02/07/13 11:53 AM

I haven't binoviewed with mine yet, and EdZ points out there may be some issues.

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Re: My First SCT new [Re: aa6ww]
      #5666983 - 02/07/13 12:13 PM

Ralph,

Quote:

My little orange tube C6 is also razor sharp with no detectable image shift in the focuser.




Happy to hear that. I've heard so many reports about image shift - as well as focus slip, which is even more of a pain - in Cats that it's nice to find out that some actually work smoothly. When I saw that my C6 could handle temps in the '20's last night without shifting or slipping, I was pleasantly surprised.

Quote:

I watched the GRS transit jupiter last night from about 9pm to 11pm on my patio which faces south.




I think I went out soon after the GRS had passed beyond the limb. Maybe next time I'll catch it. I'm looking forward to Saturn, Mars and the Moon, also. And a nice grab-n-go scope like the C6 will be great for double stars.

Quote:

I also took a look at the sombrero galaxy in corvus along with the asterisms jaws and the stargate, all three were excellent views. I also looked at m66 and m67 in leo, trying to see all three of the leo triplets but had to use advert vision to see the third ngc galaxy.




Lately my neighborhood has seen more light pollution from neighbors who like to have outdoor lights on all night, so I've pretty much given up on galaxies here at home. Last night was a surprise, though, because all the neighbors right around my usual home site had their lights off. Hit or miss at the Light Pollution Lottery here in Red Zone Suburbia.

But for the faint fuzzies, I take my 10" Dob to a dark site. I only take a smaller scope like the C6 there if I want to travel light and allow more room for my family.

Mike


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Sarkikos
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Re: My First SCT new [Re: t.r.]
      #5667005 - 02/07/13 12:28 PM

t.r.,

Quote:

I haven't binoviewed with mine yet, and EdZ points out there may be some issues.




Yes, I've read many posts by EdZ warning about induced SA and reduction of clear aperture caused by binoviewing Cats, specifically the C6. It makes sense to me, but EdZ is somewhat of a spoiler.

I was thinking about binoviewing with the C6, but at this point I've accepted the idea that it is more trouble than it's worth. There may be solutions that can allow BVing the C6 with minimal increase in SA and decrease in CA. On the other hand, those solutions would cost beaucoup d'argent. Not very cost effective for a $400 telescope.

I'm resigned to allowing the C6 to do what it does best. It is a great grab-n-go Cat for Moon, planets, doubles, and bright DSO. Having to bring along a binoviewer and multiple pairs of eyepieces acts against the idea of minimalist grab-n-go and apparently also diminishes the optical performance of the C6. Not too good. A lose-lose situation.

Mike


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Re: My First SCT new [Re: Sarkikos]
      #5667221 - 02/07/13 02:45 PM

I agree...plop in the Baader zoom and your set for the night.

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Re: My First SCT new [Re: t.r.]
      #5667478 - 02/07/13 04:58 PM

Yes, the Baader Zoom 8-24mm with the Ultrascopic 35mm for low power.

Mike


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Re: My First SCT new [Re: Sarkikos]
      #5668685 - 02/08/13 10:45 AM

I binoview with my C6 every time I use it. You're all out of your minds with this loss of aperture stuff. It still works and gives great views. Do what you want, but not using a binoviewer because someone figured on paper that you lose aperture with a long accessory optical path is just plain foolish. No offense - I do appreciate the technical objective here, but in practical terms I don't find it significant. So a C6 is really only roughly a C5.5 with a visual back, 1.25 diagonal and a Denk binoviewer. Yeah? I don't get it. Huge placebo effect here.
-Rob

Edited by rguasto (02/08/13 01:41 PM)


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Re: My First SCT new [Re: rguasto]
      #5668753 - 02/08/13 11:15 AM

For deep sky objects, I only monoview. I'm used to looking for objects toward the LM of my 10" Dob at dark sites. I don't want to do anything that might dim the image. So I've never made a big effort to bring out the binoviewer and eyepiece pairs for anything but the planets and the Moon.

However, for the Moon and planets I'm trying to see as much detail as possible in whatever telescope I'm using at the time. A reduction in aperture will reduce resolution, and that will in turn reduce the level of detail and perceived contrast in the image. A C6 binoviewed will be running at a reduced aperture.

From what I've gathered reading threads here on CN, my current setup that I have available for 2" visual back, 2" diagonal and Burgess Binoviewer will probably reduce the effective aperture of the C6 to 5". (I want to avoid a 1.25" VB and diagonal for fear that it would not be able to securely support a binoviewer.) That will not only decrease the aperture by an appreciable amount but also increase the effective central obstruction, not a good thing - especially when observing planets - for a scope that already has 37% CO.

And all this is not even touching on the spherical aberration induced by an accessory train that is much longer than that originally engineered for the C6.

Besides, I intended my C6 as a grab-n-go scope. Bringing out and setting up a binoviewer would lessen ease-of-use and light-weight that I look for in a grab-n-go setup.

If anyone else wants to binoview a C6, they're more than welcome to do it. But for me now, it's not on my top list of things to try.

Mike


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Re: My First SCT new [Re: rguasto]
      #5668825 - 02/08/13 11:50 AM

Quote:

...Do what you want, but not using a binoviewer because someone figured on paper that you lose aperture with a long accessory optical path is just plain stupid. No offense - I do appreciate the technical objective here...




The words "stupid" and "no offense" are not a very effective combination.

Tracing the rays of an optical path, finding vignetting therein and choosing to avoid it are the actions of the un-intelligent? I appreciate the hyperbole, but the statement suggests that those of us who appreciate factual information and choose to act on it are less intelligent than those who ignore it.

Facts aside, there's no reason not to do whatever one wants-- this is, after all, an aesthetic pursuit.


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aa6ww
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Re: My First SCT new [Re: rguasto]
      #5668871 - 02/08/13 12:13 PM

Quote:

I binoview with my C6 every time I use it. You're all out of your minds with this loss of aperture stuff. It still works and gives great views. Do what you want, but not using a binoviewer because someone figured on paper that you lose aperture with a long accessory optical path is just plain stupid. No offense - I do appreciate the technical objective here, but in practical terms I don't find it significant. So a C6 is really only roughly a C5.5 with a visual back, 1.25 diagonal and a Denk binoviewer. Yeah? I don't get it. Huge placebo effect here.
-Rob





Aren't these forms funny! You can tell who doesn't have a clue what they are talking about by reading in these forums. I find it best to just let them say what they want and just die laughing at how stupid it can snowball out here. The worse absolute worse ones are the ones who try to use mathematics to justify something, once I see that, its a dead ringer that person is completely clueless as to what hes not only saying, but doing. Its like that everywhere though, just chalk it up to entertainment and wait for night time. Show me an astronomer whos had the same scope for half a dozzen years and thats the guy who knows what hes talking about, then its just experience talking, not bs. Usually he owns a big old newt or a beat up cassagrain no one would be seen dead with, and almost always without electronics guiding his scope, and thats the one worth listening to and talking to, about whats in the sky, not what hes looking through. Back on the binoviewer, the real value with them is how much more contras they add to what your looking at. Two cheap orion plossls in a quality binoviewer will give you much more contras on whatever your looking at, than a whole room full of single eyepiece Ethos, every time, on any object. Amazing how much more you can see with two eyes vs one.

.... Ralph


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Re: My First SCT new [Re: aa6ww]
      #5668943 - 02/08/13 12:43 PM

I often binoview with my 8" and 10" Dobs. My Burgess Binoviewer model 125C has about a 20mm clear aperture. As long as I do not binoview with eyepieces which have field stops wider than about 23mm, I shouldn't have to be concerned about vignetting. These are facts.

The C6 has a clear aperture of 27mm. If I introduce a long accessory train behind the C6, there will not only be vignetting, reducing the effective aperture of the telescope, but also induced spherical aberration. These are facts.

Now whether or not vignetting, reduced aperture or spherical aberration matter or not to the observer - or whether or not the observer will even notice them - is something else entirely. But that has nothing to do with the fact that there is vignetting, reduced aperture or spherical aberration.

Personally, I don't have a great love of mathematics. I will avoid it whenever possible. But I know that a combination of mathematics and hands-on experience will get you closer to the truth than anything else.


Mike


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KerryR
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Re: My First SCT new [Re: Sarkikos]
      #5668951 - 02/08/13 12:46 PM

Quote:

...But I know that I combination of mathematics and hands-on experience will get you closer to the truth than anything else.


Mike




Well said.


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KerryR
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Re: My First SCT new [Re: aa6ww]
      #5668992 - 02/08/13 01:09 PM

Quote:

...
The worse absolute worse ones are the ones who try to use mathematics to justify something, once I see that, its a dead ringer that person is completely clueless as to what hes not only saying, but doing.
...

.... Ralph




Folks who use and understand physics are essentially full of doo-doo?

This relegates most of the ATM forum, not to mention the folks who design the systems we all use, to the trash heap-- opticians, amateur or otherwise, find math and raytracing extraordinarily useful. Most have looked through a scope or 2, as well. Not saying the opticians bat 1000, the HST being an example that comes to mind readily, but, more often than not, the math works pretty darn well, even if I don't understand it, or my eye-brain doesn't want to agree.


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BigC
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Re: My First SCT new [Re: aa6ww]
      #5669060 - 02/08/13 01:36 PM

Ralph,

Your post is a real eye-opener.

Just remember that opinion doesn't always equal fact.

And what works best for you may not be best for someone else.

Binoviwers are one of my options every time I observe.


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rguasto
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Re: My First SCT new [Re: KerryR]
      #5669078 - 02/08/13 01:40 PM

oh... didn't mean to ruin this thread. Maybe shouldn't have used the word "stupid" and it wasn't meant in a derogatory manner. I couldn't find a more appropriate term. I cannot detect any increase in SA and the images are full of detail as are typical of a binoviewer in any telescope. I only binoview planets (and the moon, but not a big fan of lunar) I can say that the images in the C6 compare very favorably to my 8" F8 newt with an 18% CO. The newt is obviously brighter and produces a much sharper/detailed image. IMO binoviewed planetary images are more detailed than in mono with a C6. Try it, you'll like it.
-Rob


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aa6ww
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Re: My First SCT new [Re: BigC]
      #5669128 - 02/08/13 01:59 PM

Quote:

Ralph,

Your post is a real eye-opener.

Just remember that opinion doesn't always equal fact.

And what works best for you may not be best for someone else.

Binoviwers are one of my options every time I observe.





I use them on 5/5 seeing conditions when I want to get the absolute best views possible when using my C14 when watching solar system events or during solar observing. The contras advantage with my solarmax 90 during this solar maximus is scary. Filiments you cant even see with one eye, looks like snakes crawling along the solar surface with a binoviewer. Then again, thats for a whole different forum to discuss.
This C6 subject has sparked my interest in my little C6 again. Here in Calif we are showing clear all weekend. Im planning to "pimp out" my little orange tube C6 tonight with my 2" accessories and see how many NGC objects I can bag with it. I hope more out here are having clear skies also this weekend, since its a new moon weekend. Good luck to those getting out with their gear tonight.
Once Im set up later, I think I'll take some photos of my C6 and start a new photo thread on the C6. These are great little.scopes optically the deserve way more.respect than they get.

.....Ralph


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BigC
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Re: My First SCT new [Re: aa6ww]
      #5669289 - 02/08/13 03:37 PM

Unless using binoviewers lower the image brightness "over the cliff" I would expect a signicant improvement in detail seen.In everday life my binocular vision allows depth perception and detail is lessened if I close even my weaker eye!The more raw information we can give the brain evidently the better picture it will present.

Denkmeiers are not in my budget;Williams Optics binos have to suffice.

Remember,it IS all in your head!

Should another Z12 OTA find its way here, I fully intend building a JMI clone variant.Guess I could build a smaller version first using a couple smaller tubes.Won't be all the fancy motors ,just adjustable with threaded rods or screws or something.


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Stephen Strum
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Re: My First SCT new [Re: Sarkikos]
      #5669400 - 02/08/13 04:48 PM

Per one of these loss of aperture threads I decided to try and improve my binoviewer setup for use with my C5. I've ordered an adapter from Precise Parts: http://www.preciseparts.com/ppmain/adapter.html
that will allow me to screw my denk IIs (with power switch) directly to the body of a 1.25" astro-tech diagonal (what I normally use on the C5). They didn't have that diagonal in their database, so I sent them the eyepiece holder portion of the diagonal so they could add it to their database and I could place my order. This alone will save about 30 mm of light path. Additionally, I cut off another 5+ mm off the 1.25" visual back using a rotary tool. I cut off part of the threaded portion on the end of the visual back which I didn't need. So, the combination of the two modifications will now result in only a very minor aperture reduction using the power switch when in the straight through mode (no reducer or barlow lens slid in), and should give just about full aperture if I don't use the power switch based on my understanding of loss of aperture beginning once the light path past the back of the scope exceeds 200 mm. The total cost, with shipping of the adapter was $94. The adapter won't allow me to rotate the binoviewers, but since I use my SCTs on alt-az amounts, that isn't a concern for me.

While using the 1.25" diagonal with the denk IIs and power switch might look a bit scary, I've never had a problem. On the other hand, I've had the body of my 2" SCT diagonal spin upside down with my binoviewers in them (it decided to partially unthread itself). Luckily my binoviewers didnt fall out and crash to the patio.

Steve


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aa6ww
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Re: My First SCT new [Re: Sarkikos]
      #5669485 - 02/08/13 05:40 PM

Quote:

I often binoview with my 8" and 10" Dobs. My Burgess Binoviewer model 125C has about a 20mm clear aperture. As long as I do not binoview with eyepieces which have field stops wider than about 23mm, I shouldn't have to be concerned about vignetting. These are facts.

The C6 has a clear aperture of 27mm. If I introduce a long accessory train behind the C6, there will not only be vignetting, reducing the effective aperture of the telescope, but also induced spherical aberration. These are facts.

Now whether or not vignetting, reduced aperture or spherical aberration matter or not to the observer - or whether or not the observer will even notice them - is something else entirely. But that has nothing to do with the fact that there is vignetting, reduced aperture or spherical aberration.

Personally, I don't have a great love of mathematics. I will avoid it whenever possible. But I know that a combination of mathematics and hands-on experience will get you closer to the truth than anything else.


Mike




Sometimes you just gotta be an outlaw and live on the edge, and push those fields of views over the edge and vignette a little to see what its like. Its an exhilarating experience knowing your breaking the laws of physics and mathematics, just to see whats over that barrier.
Kinda like star hoping to an object you cant see with your naked eye, but you know its there, even with a street light shining in your face. It still works, and the experience can leave you breathless. These ARE facts also!!!

....Ralph


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Sarkikos
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Re: My First SCT new [Re: aa6ww]
      #5669504 - 02/08/13 05:51 PM

Maybe you just didn't notice it.

In any case, SA would be introduced by the extended length of the accessory train in a Cat. It has nothing to do with the clear aperture of the binoviewer.

Mike


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azure1961p
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Re: My First SCT new [Re: Sarkikos]
      #5669743 - 02/08/13 08:45 PM

I can appreciate not letting the numbers and so on create unfounded biases and such but all the same it's good to that've the facts regardless.
What's truly testament here us the success of the bino view on contrast despite the apparent aperture reduction.

Pete


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Sarkikos
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Re: My First SCT new [Re: azure1961p]
      #5673622 - 02/11/13 08:33 AM

It makes sense to me that an SCT has only a finite range for length of the accessory train before spherical aberration is introduced into the system. The primary mirror has a spherical figure and must have native spherical aberration. The corrector plate is designed to correct the spherical aberration from the primary. There must be an optimum focal setting for this correction. If the eyepiece is set too far back from that optimum setting, spherical aberration will be induced. Spherical aberration prevents sharp focus of the image. Lack of sharp focus will prevent the observer from seeing finer detail.

True, binoviewing can increase perceived contrast for images. That's why I binoview planets and the Moon through my Dobs. But extending the accessory train in Dobs will not induce spherical aberration. I need an OCA to come to focus, but there is no induced SA.

Depending on how much the length of the accessory train is increased in an SCT through binoviewing, the improvement in perceived contrast could be overwhelmed by the increase in spherical aberration. For planet and lunar observation, where discernment of fine detail is all important - at least in my view - I would want to avoid spherical aberration. I think I'd rather improve contrast through other means, such as filters, baffling, closer collimation or better eyepieces.

The tradeoff for deep sky observation through SCTs might be in favor of binoviewing - at least for the brighter DSO - because an increase in perceived contrast would be helpful, while sharpness of image is often not as important as in planet/lunar observation. But I don't binoview deep sky, only planet/lunar, so I don't see that binoviewing my C6 would be beneficial for me. I don't want to do anything that would diminish image sharpness when I observe planets or the Moon.

And all this doesn't even touch on the decrease in clear aperture and increase in central obstruction ratio due to extending the length of the accessory train through binoviewing. These factors will also rob the optical system of much needed contrast and resolving power when viewing planets and the Moon.

Mike


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aa6ww
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Re: My First SCT new [Re: Sarkikos]
      #5680531 - 02/15/13 01:15 AM

You should probably read up on what a corrector plate does, which all SCT's have. You'd probably stop talking about spherical aberration regarding SCT's which your newts have, which SCT's design out of with their front correctors.

..kinda funny!!

...Ralph


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Sarkikos
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Re: My First SCT new [Re: aa6ww]
      #5680764 - 02/15/13 07:15 AM

Not really funny. Just optical engineering. But you are an engineer, so I should think you'd understand that.

On the other hand, I had a engineer working with me who continually asked me to correct problems on his computer and show him how to use software. Finally I became aggravated and told him, "You're the engineer. You should be telling me how to do this!" He answered, "I'm a civil engineer, not a computer engineer." I guess there are engineers, and then there are engineers.

Newts have SA corrected by having the primary figured into a parabola. SCTs have SA corrected through use of a corrector plate. The primary in an SCT has a spherical figure. It stands to reason that the corrector plate will correct the SA optimally within only a certain distance range from the primary. Position the eyepiece outside that range and SA may be introduced into the optical system. A specific observer might not notice it, but it will be there. It would probably be most noticeable at higher magnification when observing - or attempting to observe - details on the Moon or planets. Probably, though, the worst effects from increasing the focus are vignetting, reduction of clear aperture, and increase in CO ratio. These can also decrease resolution and perceived contrast for the image.

If you mostly view DSO at low power it might not be such a big deal. For example, I have a 4.5" f/4.4 Ball Scope with a spherical mirror. I've gotten decent low-power rich-field images of DSO with this little telescope. It gave me one of my best views of the Double Cluster and Stock 2. And years ago it was the first telescope which showed me M78 here in red zone suburbia. But try to pump up the power for fine detail on the Moon or planets? Forgetaboutit.

Mike


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