A star diagonal gets around this issue, and use the diagonal when planetary imaging, 1 can swap out eyepiece centre planet in centre of eyepiece field then slip in the camera, so another advantage if using diagonal.
Been just looking at the QHY 183C not for astrophotography but EAA and using 1.25 eyepiece adapter and using in diagonal.
So how do I go about backfocus and what would it be with a 0.5x reducer screwed into eyepiece adapter and back focus on a 9.25 evo SCT, non HD version, or does back focus not so much a concern with EAA, cheaper cameras its never mentioned like cheap planetary cameras, etc, get into more expensive CCD cooling cameras its suddenly an issue, yet does not the SCT have the most focus available of just about anything?
This may seem stupid, but the diagonal on these 1 arm bandits gives full travel of mount
Edited by robodan, 24 February 2021 - 09:55 PM.