celestron c8 queries

[iwols]

hi all just a few questions for anyone with a c8 xlt tube thanks 

1 does it use a 2" eyepiece

2 does a dslr fit ok

3 can you fit a  qhy5 ii mono camera for guiding with the supplied finder scope

4 would my 2" diagonal off my sw ed80 fit

thanks as always

[michael.h.f.wilkinson]

I got a separate 2" visual back for mine (quite cheap), and added a regular (push-fit) 2" diagonal to it. I now use a range of 2" EPs. I also have a T2 back for it, which fits both full-frame and APS-C cameras well. The original 6x30 finder scope on my C8 is unsuitable for guiding. Given the optics, I would certainly go for an off-axis guider.

[Davesellars]

Regarding 1 and 4 (same thing), yes but you need to remove the 1.25" visual back and replace it with a 2" visual back.  I recommend while a bit expensive the Baader ClickLock SCT - 2" as it grips like a vice.

2. Yes, you will just need the typical t-adapter - 2" and t-ring.

3. No you will need a good finder-guider or small refractor.  Note at this focal length and for long exposures you're going to be dealing with flexure and the need for very accurate polar alignment and tracking.  So make sure your mount is up to it.

[iwols]

Thanks Guys so i would need thé 2 inch visual back ,,does this come seperate and does that. Just screw onto thé back of the scope,

 

 

 

[michael.h.f.wilkinson]

The C8 OTA comes with a 1.25" visual back. You can unscrew this, revealing what is known as the SCT-thread. You can then screw the 2" version on (or a focal reducer, or T-2 adaptor).

 

[iwols]

And would the 10x50 scope off m'y éd80 be any good

[iwols]

1 minute ago, michael.h.f.wilkinson said:

The C8 OTA comes with a 1.25" visual back. You can unscrew this, revealing what is known as the SCT-thread. You can then screw the 2" version on (or a focal reducer, or T-2 adaptor).

 

Thanks

[YKSE]

23 minutes ago, iwols said:

And would the 10x50 scope off m'y éd80 be any good

The mounting shoe for finderscope on my 80ED and C8 are the same Vixen style (new Skywatcher and Celestron socpes have this), so it should fit.

[michael.h.f.wilkinson]

The 10x50 finder might fit, and is certainly better than the 6x30 I have on my C8 (now augmented by a 14x70 home-brew RACI finder), but is still very short for guiding at 2020mm focal length.