advice for OAG + guiding camera for C8 (6.3 reducer)/VX mount with Canon

[Erquy]

Hi,

I know there are a number of topics on the subject, but I could not really find a straight answer on proven recommandations as in many cases some issues are reported or people who are in the same situation as I am... intend to buy.

So my question is: can someone recommand a proven OAG adaptor + ccd guiding camera to set on my (coming) C8 (with celestron reducer 6.3) mounted on the new VX and to be used with canon EOS as main camera.

I saw a number of topics where it is mentioned issues to get both focus on the main camera + guiding camera, also possible need for extension, adaptors and so on.

After reading, my idea would be to go for

- celestron radial off axis (the TS 9mm Off axis seems a bit "light", apparently not easy to move the little prism, not that robust according to some reports, please confirm/comments)

- as camera, several choices:

1) QHY5, among the cheapest out there, but I understand not the most sensitive

2) starlight lodestar, seems to be highly recommanded and good starting CCD

3) starlight costar (a cheaper "lodestar", but as I understand same CMOS as QHY5, so I assume maybe similar noise/limited sensitivity as QHY5?)

3) alccd5-II: another affordable CMOS also, but once again how does it compare to the costar or QHY5?

The lodestar is most likely a secure buy as ´many good reports, but also most expansive of above, but the alternative above may be good enough in a C8+6.3 reducer with celestron radial off axis?

Would any of such combination work well? Combined focusing issues? Any one can say using successfully such combination DSLR + celestron radial off axis + one of those camera on a C8 with focal reducer 6.3? How long exposure time can you achieve?

Thks in advance

[Davey-T]

Just yesterday I purchased an Atik OAG to fit on my Meade 10" SCT with 6.3 f/r , I also recently purchased a Loadstar ccd to go with it.

I have tried OAG a while ago with different stuff but gave up so now making a big effort with hopefully better equipment.

As you say the Loadstar appears to be the camera of choice so given the somewhat restricted FOV on the scope I think it's best to go for the most sensitive camera to get the most guide stars.

I'll be using an Atik camera but will also try DSLR , not sure if the prism will get in the way with a DSLR , you may have to orientate the cameras so the guider is on the long side of the DSLR

frame.

Will try it all out as soon as possible as the song says "I'm sure we'll have some fun if it stops raining"

Dave

[Erquy]

Also I noticed that Celestron has introduced recently a new version of their OAG: simply called now "Celestron off axis guider" (instead of previous "radial off axis"). It seems to come with a package of adpaters to fix any focusing issues. Seem also even more robust than previous one. I would certainly go for this one.

http://www.firstlightoptics.com/off-axis-guiders-oag/celestron-off-axis-guider.html