M45 Pleiades with 5-inch AP apo at f/6. With Canon 20Da camera at ISO400. Stack of four 15-minute exposures. Taken from home Nov. 20.
M45, Pleiades, long exposure to reveal surrounding faint reflection nebulosity. Taken January 17, 2009 with 77mm f/4 Borg astrograph refractor (300mm focal length) and Canon 20Da camera at ISO 400 for 4 x 18 minute exposures. Some RA trailing on 3 of the exposures for some reason.
M45, the Pleiades star cluster, in a series of exposures to test stacking images with HDR techniques. I shot the cluster 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. Diffraction spikes added in Photoshop with Astronomy Tools actions.
