RC, Newtonian Astrograph, or Edge HD

HELP!!!! Looking to purchase a new OTA for imaging. I would like to hear your input about the 4 OTA's I have narrowed it down to. I am a refractor guy but I like the images more and more that I am seeing posted with these various scopes. It will be in a permanent observatory. Mount not an issue..CGE Pro
I am looking at the following:

1-GSO 10" RC Truss Tube
2-GSO 10" RC Solid Tube
3-EDGE HD 8" with .7 Reducer and Moonlight Focuser
4-GSO 10" Truss Tube Imaging Netwonian
Thanks in Advance
Bob

Hi Bob,
what kind of camera do you use? Do you prefer just deepsky imaging or planetary imaging too? :-)
Vittorio

Hi Vittorio,
I am a deepsky imager. I use both a SX 694 Mono and ZWO ASI1600MM-C. I have thought about some planetary but have never really imaged anything except the moon when I started out , which is what got me hooked on this hobby in the first place..

Bob

On my opinion every scope has advantage and disadvantages. Newtonian is a good instrument, but probably it is harder to handle (collimation and balancing above all). Also the edge HD is a good instrument, but I'm not sure that the difference of prize with a C8 "normal" can be justified.
A lot of people use the GSO RC, I think that for deepsky it could be a good choise. But also in this case you need a flattener for a big sensor as ASI 1600, I think.
Truss or solid tube? I dont't know…could be interesting to compare them by mechanic side.
On this site you can found every kind of wonderful images made with all tubes you wrote :-)
For me is very hard to choose a tube between the others.
Sorry for my english :-)

Vittorio, Thank You my friend. They all have their pros and cons. I agree with you..it is hard to choose between them. This is why I am asking for input from the AstroBin community!!! I am at an impasse here.

By the way your English is just Fine!

Hi Bob,
I have some information. Usually the difference between an RC Truss or solid tube is about the weight, but I notice that the weight are very close.
Another thing…for me 10" are better than 8"…but you have to do some considerations…I think that also the price could be a discriminant.
If I can give you my opinion…do you prefer a tube in particular? TAKE IT

Probably if I had to buy a new telescope for astroimaging I'd buy 10" truss

Recently I bought a C8 tube (non edge), but in Venice I have also another problem, the salt in the air because I stay close to sea, so for me a closed tube is better than an opened one as RC.

Hi Bob,

I think it is also a question of your preferable focal length. I use for example a 8" newtonian with 800mm and a 8" RC with 1.624mm. So it is a complete different field of view and both scopes have their own targets.

But one remark: If you prefer a closed tube you should think about one which is made with carbon! No more focus drifts in cold nights

Frank

I replaced my Newton with an EdgeHD becuase of the many travelling for the dark sky and I like it very much, becuase it works quite stable and easy to handle, ,which saves a lot of time, but if I had a fixed place I would use again the Newton I think. I dont like the collimation, the open tube, the diffraction spikes of the Newton, even the guiding is worse sometimes because of the size, but I like the better contrast on the picture and finally this is what matter in AP.

Hi Bob,I think it is also a question of your preferable focal length. I use for example a 8" newtonian with 800mm and a 8" RC with 1.624mm. So it is a complete different field of view and both scopes have their own targets. But one remark: If you prefer a closed tube you should think about one which is made with carbon! No more focus drifts in cold nights

Frank

Thanks Frank, I totally agree on the carbon tube vs a steel tube for the focus change. I to have 2 refractors for various field of views . My present setup consists of a SV130T at 910mm f/7 and a SV70 at 334mm f/4.8. Although both have really nice qualities, I am liking the pictures out of the RCs and Newts more and more. They seem to have better contrast and deeper color.

Thanks
Bob

I replaced my Newton with an EdgeHD becuase of the many travelling for the dark sky and I like it very much, becuase it works quite stable and easy to handle, ,which saves a lot of time, but if I had a fixed place I would use again the Newton I think. I dont like the collimation, the open tube, the diffraction spikes of the Newton, even the guiding is worse sometimes because of the size, but I like the better contrast on the picture and finally this is what matter in AP.

Thanks Peter..I had an EDGE HD 1100 but I sold it to fund my Refractor habit. I have been considering the Edge 8" this time with an extrernal Moolight focuser. Part of me still really likes the focal length of the SCT. My biggest concern with the SCT was Mirror flop. I was never happy with the focus,but I am thinking the external focuser should almost act like an RC in this respect. Even tough I have the SCT lower on my list it fits my budget better with all of the additional accessories.

CS
Bob

I don't think there is a right answer. I have seen totally outstanding images with all of these scopes. In fact I have seen way superior images with e.g edge HD than in some cases scopes many multiples of the price! Same for lower cost RC's and imaging newts. Nowadays I think optical manufacturing has evolved to the point where the differences are not nearly what they used to be in my opinion. Technical differences with respect to collimation, backfocus etc exist but really nothing that makes or breaks the decision. Perhaps cost should be your guide.
Best of luck and enjoy your new scope!
Regards
Dave

Ive had one of each over the years. These days I've settled in with my AT 10" RC Truss Tube. Works well with my Mach 1 GTO, even if at the edge of capacity. Great light gathering power at 200mm, decent FOV at f/8, but I am installing an APCCD T67 FR. None of the SCT's Ive had came close in terms of contrast and no focus issues with an RC. You can pics at my profile.

SCT versus RC. The SCTs spherical mirrors have aberrations that are not as easily corrected as those from the RCs hyperbolic mirrors. But, those hyperbolic mirrors are very sensitive to collimation. Some people collimate their RC just fine, others have sold the scope out of frustration.

This is why there are very high end RCs, but no very high end SCTs.

I own a 6RC. Collimation was a struggle, but I got there. Now the problem is focuser sag/tilt. Some people install a Moonlite, which costs more than the scope.

Hey Bob, I think you are quite an experienced guy in this question and also generally, you should choose the one with the most challenges for you

SCT versus RC. The SCTs spherical mirrors have aberrations that are not as easily corrected as those from the RCs hyperbolic mirrors. But, those hyperbolic mirrors are very sensitive to collimation. Some people collimate their RC just fine, others have sold the scope out of frustration.This is why there are very high end RCs, but no very high end SCTs.

I own a 6RC. Collimation was a struggle, but I got there. Now the problem is focuser sag/tilt. Some people install a Moonlite, which costs more than the scope.

Being a refractor guy ..collimation is my biggest fear while trying to choose. I too have seen many RCs on Astromart for the reason you mentioned. For sale due to frustration. lately the skies here in Pennsylvania have been so bad due to the weather that I would hate to waste imaging time for technical difficulties.

Thank You
Bob

Hey Bob, I think you are quite an experienced guy in this question and also generally, you should choose the one with the most challenges for you

I don't think there is a right answer. I have seen totally outstanding images with all of these scopes. In fact I have seen way superior images with e.g edge HD than in some cases scopes many multiples of the price! Same for lower cost RC's and imaging newts. Nowadays I think optical manufacturing has evolved to the point where the differences are not nearly what they used to be in my opinion. Technical differences with respect to collimation, backfocus etc exist but really nothing that makes or breaks the decision. Perhaps cost should be your guide.Best of luck and enjoy your new scope!
Regards
Dave

Thanks Dave for the input. My sentiments exactly. That is why I have the Edge HD 8 on my list. With all of the accessories, FR/Focuser/ dew shield/extra dovetail etc the price is still less than the others alone. I seen some really good pictures from the SCT and some not so good. I had an Edge HD 11" but struggled with image shift even with the mirror locks.. I think adding the external focuser should handle this perhaps.

Thank You
Bob

Jeff Bennett:
Ive had one of each over the years. These days I've settled in with my AT 10" RC Truss Tube. Works well with my Mach 1 GTO, even if at the edge of capacity. Great light gathering power at 200mm, decent FOV at f/8, but I am installing an APCCD T67 FR. None of the SCT's Ive had came close in terms of contrast and no focus issues with an RC. You can pics at my profile.

Thanks Jeff ..your images are great. Exactly the reason the RC is #1 on my list!!

Thanks
Bob

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