What is the correct back focus for a ASI 2600 Duo on a Celestron. C8 SCT? How many mm is the camera itself? Thanks newbie here.
The SCT Back focus distance from primary mirror baffle tube lock ring for the C8 is 5" (12,7cm) and the 2600MC Duo Back focus is 17.5mm from tilt plate.
But it's very dificult to use an 2600MC Duo with the C8 because the camera needs 42mm opening diameter. It doesn't work on my C9.25 as well. The guide sensor is very vigneted.
https://www.celestron.com/blogs/knowledgebase/what-are-the-optimum-back-focus-distances-for-celestron-scts
DeepSkyOne thanks for the info. I’m hoping I can get it to work. If not I guess I have to get a new telescope
Hmm. I don't think the image circle of the C8 SCT is large enough.
https://youtu.be/R5lfd5lldlg?si=RZk6RVdxXZb_J36G
AstroWorkz video. Skip to the section about image circle.
I have a C8 SCT. I'm not sure what the image circle is for it, though.
Corsair Thanks for the info. I will take a look at the video.
Can you all recommend a better ZWO cooled camera for the C8 SCT?
You can use any camera with an APS-C sensor size, except the 2600MC Duo. The 2600MC Duo camera is near of a full format size. The C8 can't handle that.
May as well use the Duo but with a guider on the C8?
Price difference between a duo and standard 2600 is not a lot, then you have future options if you want to use the Duo with other OTA.
Yes, that's always an option, but isn't easy to find an 2" (SCT) adapter to M54 (Cam).
Thank you all for the great information. I think i am probably going to go with a 2600 MC pro with a 220 MM as a guide scope. Hopefully that will solve my problem. Is the proper back focus still 105mm?
The 105mm of the back focus only applies when using the Celestron f/6.3 Reducer. Different reducers could have different back focus.
Cameras do not govern or have anything to do with backfocus. Only optics do.
