Last night I used the 8" RC with focal reducer (F/5.4) and the ASI1600MM-C Pro to take this image of the Crab Nebula. In total I shot 72 minutes of L and 36 minutes of R, G and B each. I did this in series of 3 x L, 1 x R, 1 x G and 1 x B with 120 sec L and 180 sec each of R, G and B. The light pollution is very unevenly distributed in my backyard with much more of it to the east. So by shooting in series like this I spread out the change in background over the imaging session and over each filter instead of over just one of them.
Processing, light pollution removal, background color calibration and star color calibration were done in AstroPixelProcessor. Then I used Gimp to apply Levels (darkening the background), Saturation, Sharpening and Cropping.
ASI1600MM-Pro Cooled and filter wheel with a SkyWatcher Esprit 80 ED on a SkyWatcher HEQ5-Pro
ASI1600MM-Pro Cooled and filter wheel with an 8" TS Ritchey-Chrétien on a SkyWatcher EQ6-R