M31 with 5-inch AP apo at f/4.5 with telecompressor/field flattener and Canon 20Da camera. Stack of four 15-minute exposures + two 2-minute exposures for the core. Taken from home Oct. 15, 2006. Image sharpened with 10 and 50 pixel High pass filters.
A test image of M31 taken for a book illustration using an entry-level deep sky setup to show what’s possible. This was with the SharpStar 76mm EDPH apo refractor on the Sky-Watcher EQM-35 mount, and guided with the ASIAir Pro and guidescope and the iPad app. The setup costs about $3000, about the minimum for a good deep sky rig for shooting with a telescope. This is a stack of 16 x 4 minute exposures with the Canon 60Da and with LENR on for all frames, so 64 minutes of actual images but an equal number of dark frames subtracted in the camera over 2 hours total of shooting. Taken Sept 16, 2020 under clear but smoky skies. All stacking, alignment and processing with Photoshop with Raw files developed in Adobe Camera Raw.
M31, Andromeda Galaxy, with companions M32 and M110. Taken with 92mm TMB apo refractor and Borg 0.85x flattener/compressor, and Canon 5D MkII camera at ISO 400 for stack of 4 exposures x 10 minutes and stack of 2 exposures x 2 minutes (for the core) blended in Photoshop with layer mask. (Photomatix HDR did not work -- images did not align, due to field rotation?). North is up in this vertical orientation.