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View Full Version here: : Choice between two (maybe more) scopes.


GazzMeister
12-01-2008, 10:43 PM
Good evening All

I'm a bit of a newb and I've got a hypothetical question. If you had to choose between a celestron cpc-11 (with the added cost of a wedge) or a celestron advanced c11, what would your choice be? Obviously different scopes, but which would you choose and what would influence your choice? If anyone has any other ideas of comparable scopes please include them also.

Gareth

Zuts
13-01-2008, 12:16 AM
Hi,

I have a nexstar 11 and the optics are fine, the CPC 11 optics are probably marginally better as the coatings are a bit better. There should be no difference between a CPC 11 and advanced as the OTA is pretty much the same.

The problem with the advanced is that they stuck an 11 inch OTA on a CG5 mount and basically it is too big for it and would be very difficult to get good images. Visually though it would be fine.

If you just want visual then go the CPC as alt az mounts are easy to set up and start viewing, compared to polar aligning the advanced.

If you are interested in photos then probably a C11 ota and an eq6 mount may be adequate. If you get the CPC then you will need a wedge. I found the Celestron wedge very hard to use and would probably get an aftermarket wedge, more expensive but far simpler to adjust when polar aligning.

I am thinking of selling my Nexstar and getting a c9.25 to put on my eq6 for photos, but then again i really like the ease of use of the alt az mount and the large aperture of the C11 so will probably keep it. Imaging is a different ballgame and i image through a small refracter on an eq6 and for visual use the C11 Nexstar.

Paul

OneOfOne
13-01-2008, 10:06 AM
I have a C11 on the CGE which is basically the same tube as used in the CPC and Advanced. Prior to this I had a C8N-GT which is an 8" Newt on the CG5 mount. Whilst the mount seemed to cope quite well with the 8" tube, the 11" SCT tube is quite a lot heavier and I think you would be pushing the limit. The cost of a CGE mount is, of course, considerably more than the CG5 or EQ6 and so is probably out of your budget. I think I would be going for the C11 tube on an EQ6. A number of people have this setup and I think the EQ6 would handle it with ease.

Although the CG5 would probably be adequate for visual, the difference in price between that and an EQ6 would make me spend a little more and get a mount that I won't be changing sooner rather than later.

edwardsdj
13-01-2008, 02:55 PM
The difficulty in using wedges with fork mounted SCTs is that the eyepiece/camera position ends up between the forks when pointed in the deep South.

Having used a wedge with forks for almost a decade now I'm keen to get back to a german equatorial mount as it was always so easy to observe/image in the deep South with one.

The alt/az computerised fork mounts do look attractive for visual use as the setup is much easier than a equatorial mounting. Having said that, the 11" SCT tube with forks attached must be pretty heavy. At least with a GEM you can detach the OTA from the mount.

Zuts
13-01-2008, 11:43 PM
The 11 inch Nexstar is heavy, but manageable. I must admit that putting it on a wedge is very scary, all that glass hanging off one bolt!

Paul

GazzMeister
15-01-2008, 08:39 AM
Thanks for the responses everyone. You've pretty much confirmed what I suspected, with the CG5 not really being up to the task of carrying an 11inch. I think I'll end up going with an EQ6 and use my 10inch for observational use with an ED80 or ED100 for a bit of occasional photographic use.

Just out of interest, what is the CG5 similar to? Is it about equal to a EQ5?

allan gould
15-01-2008, 11:01 AM
Answer: Yes
Go with the EQ6 and you'll be very happy.

OneOfOne
16-01-2008, 08:08 AM
Yep, the CG5 is basically the same "level" as the EQ5.

I don't know that there is any "standard" but there seems to be a sort of "build level" associated with each "EQ" number. If something is a "1" you expect certain things, like "cheap and nasty", probably commonly found in department and electronic stores. From a "3" you start to get something fairly well built, although I have never seen anything called an EQ2 or EQ4 :shrug: