GSO/AT 8" RC or VC200L

[Shiggy (Shaun)]

It has probably been asked before, but here goes anyway.
I'm looking at getting an 8" imaging scope and I keep coming back to these two options.
The Astrotech or GSO 8" RC
The Vixen VC200L

I know about the spider vane problem on the VC and the long image train on the RC.
How much of a difference does the F8 1625 vs the F9 1800 make?

So much to read about both but can't seem to find any good comparisons between the two!

Cheers
Shaun

[TrevorW]

The GSO is designed as an imaging scope

[allan gould]

Funny this post should come up as I was looking for an imager between my 5" apo and 10"sct. I was seriously looking at either an 8"Edge or AFC scope but the lack or a decent reducer put me off and then I also was interested in the GSO RC scopes but. Just could not pull the trigger. Then I saw some shots by 1 Ponders and Leinad on IIS with their VC200L scopes. This has an f6.3 reducer which maintains the flat field so I pulled the trigger on this scope. I'm changing over the vanes this weekend and re-collimating the scope with the help of Peter_4059 and Leinad. Hope all goes well but there is a VC200L yahoo group that you can join.
Did I make the right choice? Don't know yet.

[Shiggy (Shaun)]

Are you modding the vanes yourself Allan?

[allan gould]

Originally Posted by Shiggy

Are you modding the vanes yourself Allan?

No I purchased them from an IIS MEMBER (Leinad)

[gregbradley]

This is an interesting comparison. Both seem to be good scopes.

Greg.

[George Ionas]

The VC200L provides a full frame flat field while the GSO 8" RC is curved.

George

[Shiggy (Shaun)]

These two images are in the IIS forum, both of Centaurus A.
One is with the GSO 8" RC (Trevor W)
The other is the VC200L (Terry B)
Thanks to those who post examples.

[Shiggy (Shaun)]

Originally Posted by George Ionas

The VC200L provides a full frame flat field while the GSO 8" RC is curved.

George

Good point.
The Astrotech AT2FF flattener works with the 8" RC.

Shaun

[Paul Haese]

I have the RC in both the 8" and 12" versions. While field curvature needs to be address, I believe they produce images that are sharp and detailed. Choice is yours of course but here is a few links of images I have taken with the RC8"

http://paulhaese.net/NGC5128QSI.html (image needs a lot more data)

http://paulhaese.net/M17SwanHargb.html

http://paulhaese.net/IC2944RunningChicken.html

http://paulhaese.net/HorseheadLRGB.html

http://paulhaese.net/ThorsHelmetHaRGB.html

http://paulhaese.net/m83closeup.html

Few others in that gallery that were taken with the 8" too.

Best of luck with your selection.

[Shiggy (Shaun)]

Originally Posted by Paul Haese

I have the RC in both the 8" and 12" versions. While field curvature needs to be address, I believe they produce images that are sharp and detailed. Choice is yours of course but here is a few links of images I have taken with the RC8"

http://paulhaese.net/NGC5128QSI.html (image needs a lot more data)

http://paulhaese.net/M17SwanHargb.html

http://paulhaese.net/IC2944RunningChicken.html

http://paulhaese.net/HorseheadLRGB.html

http://paulhaese.net/ThorsHelmetHaRGB.html

http://paulhaese.net/m83closeup.html

Few others in that gallery that were taken with the 8" too.

Best of luck with your selection.

Beautiful images Paul.
The more I see the harder it is to choose as they both seem to be good imaging scopes.
Would you regard the GSO 8" RC focuser upgrade as essential for F8 imaging? I would be using a modded dslr (500D) as I haven't made the leap to a big astrocam yet.

Thanks
Shaun

[TrevorW]

Not a good comparison Shiggy

you've just can't put two images together and make a general assumption about a scope

camera, processing,exposure,guiding all need too be considered

here is another example of Cent A taken with a GSO

go too my site or Paul's to see images taken with the GSO

[Shiggy (Shaun)]

Originally Posted by TrevorW

Not a good comparison Shiggy this was done with the GSO as well

you've just can't put two images together and make an assumption about a scope

camera, processing,exposure,guiding all need too be considered

Thanks Trevor,
Thats a fabulous image.
I agree with you completely. There are so many variables to consider that comparing images probably isn't much help.
So far it looks like both scopes deliver.
The RCs are a little cheaper and don't require much modding, but I'm impressed with what I have seen from both the RC and the modded VC.
Probably also says something about my own inexperience.
Have you tried a dslr on the rc?

Thanks
Shaun

[TrevorW]

My first camera was a modified Canon 350d

[Shiggy (Shaun)]

Originally Posted by TrevorW

My first camera was a modified Canon 350d

Cool, I'm using a modded 500D at the moment (I used to have an unmodded 350D). I moved to a 500D for live view camaera focusing, which has helped but I used the 350D heavily for regular photography and loved it

[Hagar (Doug)]

I have owned both of these scopes at different times of course but should I go down this track again and I probably will my choise would be the VC200L in a heartbeat.

Both scopes need something done to the focusers. and the VC200L now has an after market focuser available.

The GSO reqires a field flattener and quite a bit of experimenting to get spacings correct while the VC200L has a built in field flattener which actually works spot on out of the box.

The VC200L has a reducer made for the scope while the GSO doesn't.

Both have a very similar focal length, weight and design style.

The VC200L has big thick spider vanes which can be machined down if you are not happy with the big stars appearing a little diamond shaped.

All up the VC200L was a lovely scope and took far less effort to get good results with. It works out of the box while the GSO has all sorts of problems.

The VC200L has a 60mm focuser and baffle tube compared to the GSO 48mm allowing the use of larger format CCDs. The 60mm focuser allows the use of 60mm extention adapters which are easilly sourced and relatively cheapto form a screw together imaging train rather than the 2" clamp up imaging train which must be used on the GSO without getting adapters made specifically for this purpose.

I am thinking along the lines of aquiring another VC200L some time in the future and feel it is by far the better option.

Good luck with your choice.

A few examples. Bear in mind these were taken some time back and I have improved processing etc a lot since these were done.

http://www.darkskyau.com/cm/displayi...152&fullsize=1
http://www.darkskyau.com/cm/displayi...117&fullsize=1
http://www.darkskyau.com/cm/displayi...116&fullsize=1
http://www.darkskyau.com/cm/displayi...116&fullsize=1
http://www.darkskyau.com/cm/displayi...108&fullsize=1
http://www.darkskyau.com/cm/displayi...107&fullsize=1

Plenty more on my website.

[Paul Haese]

Shaun, the GSO RC is an f8 system.

[gregbradley]

Noboby seems to be using the 10 inch VCL.

I think that would be a nice scope. They come up every now and then on Astromart often tricked up with accessories for about US$2600 or less. With our dollar being a bit higher than the US it may prove to be a good buy.

There is also a 300mm VCL or is it VMC? Not sure that the subtle differences are there - but its rare and around US$10,000.

Greg.

[bert (Brett)]

The larger vc/ vmc scopes have a moving primary mirror similar to a SCT. Makes them less desirable for imaging.

That said I would like to give one a try one day.
Brett

[Hagar (Doug)]

The VMC series are manufactured as visual scopes and don't have the aspherical corrector which flattens the field of the VC200L. The VC200L is designed as a flat field astrograph.