I purchased a used Edge 1100 HD not long ago. It came with the DSLR T-Adapter, part #93646, and a small visual back. Then I read the Edge HD "White Paper," all about how important it is to get the right back focus distance. No problem with the T-Adapter for my Nikon DSLR, but for the life of me, I cannot figure out what adapter I'm supposed to use for my ZWO ASI290MC. Do I use that same adapter and just screw the ZWO body onto it? Not according to the diagram on p. 15 of the White Paper. There, there is a drawing of a mystery adapter for use with CCD cameras. No part numbers are given, and I have tried and tried to figure out what that adapter is. According to the diagram, the flow is: Reducing ring > Small T-Adapter > T-to-1.25" Adapter > Astrocamera.
Until I heard about the White Paper, I was just imaging using a GSO Crayford focuser screwed onto the back of the OTA and getting some nice images, but not real crisp, and I was attributing that mainly to seeing issues. So, another question I (and a friend who also just bought an Edge 1100 HD) had was, How much is the image degraded if my imaging sensor falls too much inside or outside the recommended 5.75" sweet spot for back focus?
Any help appreciated, especially if you have a photo of that train of adapters from OTA to camera (or part numbers).
Edited by John Verderame, 12 July 2018 - 11:52 PM.