M31 Andromeda Galaxy, with TMB 92mm apo refractor and Borg 0.85x reducer/flattener for f/4.8 and Canon 20Da camera at ISO400 for 2 x 15 minute exposures. North is at bottom, south at top (better balance with this framing)
M31, the Andromeda Galaxy, in a series of exposures to test stacking images with HDR techniques. I shot the galaxy in a series of 1, 2, 4, and 8 minute exposures, four of each exposure, all using the Nikon D750 and 92mm TMB refractor. A set of 1,2,4, and 8 minute exposures was stacked in Camera Raw using its HDR mode to create a new merged DNG file. I did this for four sets of 1 to 8 minute exposures, then processed each of the HDR stacks with Shadows and Highlights in ACR to bring out faint detail but retain detail in the bright core. Each of the 4 HDR stacks was then mean combined stacked in Photoshop and processed with Curves, S&H, B&C etc. So in total this is a stack of 16 images, 4 each x 1, 2, 4, and 8 minutes.
Andromeda Galaxy, M31, with the Lunt 80mm f/7 doublet apo refractor for stack of 5 x 15 minute exposures at ISO 800 with Canon 5D MkII and Borg 0.85x flattener/reducer. Companion galxies, M31 and M110 also shown. Taken from home. Field is roughly 4 x 2.5°.