ED80 vs 6" SCT

[talfie]

I've been 'in and out' of imaging for a few years, never really getting into it to enough to work out what i'm doing (something would always pt me off!), but i'm now determined to get somewhere with this.

I've got a Celestron ED80 and Nexstar 6 SE SCT scope (removed from alt az mount), an EQ5 mount and Nikon D40.  Which scope is better for starting to get into imaging?  Is the slower SCT with a 6.3 focal reducer better than the ED80? How much does the larger aperture of the SCT compensate for the slower speed compared to the faster ED80?  Why should I use one over the other?

I have so many more questions than will probably come out of this, but i'll keep it short and simple to begin with.

Any advice would be much appreciated!

[riklaunim]

SCT will be harder for DS imaging - long focal length and primary mirror that can move a bit and defocus an image. But that all depends on accessories, guiding and experience. Then both should just work.

[laudropb]

What do you hope to image ?

[talfie]

Thanks for the replies

SCT will be harder for DS imaging - long focal length and primary mirror that can move a bit and defocus an image. But that all depends on accessories, guiding and experience. Then both should just work.

Guiding and experience are non-existent at present!  I've got a few accessories like the necessary T-adaptor, barlow lens, eyepieces, homemade cardboard bahtinov masks etc.  The Nikon D40 limits me to 30 second exposures, unless i manually stand there with the IR remote or do something more complicated.  Sounds like the ED80 might be the way to go, although I'm hazy on which is best in terms of exposure time (f7 ED80 vs f6.3 SCT with focal reducer)?  

But it sounds like trial and error may be the best way to learn and at this stage I'm going to get so much wrong that I'm going to be the limiting factor at this stage as opposed to scope choice!

What do you hope to image ?

Mostly DS, but I will do a bit of planetary webcam imaging (for which i understand the SCT is more suited although i could be wrong).

[johnrt]

They are very different scopes, have you considered the field of view either one will give you, for example the 6'SCT even with the reducer and your large chipped Nikon will only just fit M42 in the frame, not to mention the additional challenges you will face in guiding accuracy at the almost a meter focal length.

Have a play with this http://www.12dstring.me.uk/fovcalc.php

[tich]

I used to own a Celestron ED80 for imaging & its a brilliant scope, I only sold it on because a Skywatcher came up for an offer I couldn't refuse. Even the single speed R&P focuser never became an issue, just as long as you use a Bahtinov mask to focus with using live view you should be fine.

Below is an unguided image of Orion using the Celestron C80ED stars are a bit eggy but it gives you an idea, the camera used was a modified Canon 1000D.

[Chris]

ED80 for DSO imaging

C6 for planetary and Lunar imaging

[ollypenrice]

For DS the ED80. Or just a camera lens, if you're not guiding. Don't underestimate what's out there for short focal lengths.

Olly

[Vox45]

I followed that path exactly. I started with a C6 and sold it to get an SW 80ED.

My reasoning was that if I was going for DS imaging ( more targets ) I would have to invest a lot of $$ (a focuser, focal reducer, bits and pieces) and still end up with a so-so imaging system compared to a fast wide field refractor.

So I sold it and got the 80ED.

Now, I miss my C6 for planetary but I am saving for a MAK 180 which will be MUCH better than a C6 could ever be. Then I'll invest in the proper bits needed for planetary.