I've recently had an online discussion regarding this very question. It started when a friend shared a Mars image taken with a high end 10 inch TMB apo when Mars was 20.2 arcseconds. I then shared a recent Mars image taken with my C11 when Mars was 15.4 arcseconds. Neither if us are experienced planetary imagers but I believe we used about the same level of stacking and enhancing. To me the images are about of equal quality and any differences in the scope's capabilities are trivial.
I know in a head to head comparison for visual the 50k apo will definitely give the better image with better more pleasing contrast. However with its slight aperture edge the C11 will keep up for resolution and be able to keep up for the most part but still definitely loose out.
In an imaging comparison I believe a C11 can basically keep up with a 10 inch apo if similar levels of enhancing are applied. The first pic is Mars with the 10 inch TMB at 20.2 arcseconds and the second is my image on 12/26/22 with my C11 at 15.4 arcseconds. Thoughts on such a comparison??
Edited by Darren Drake, 25 January 2023 - 08:06 AM.