I went back and processed a couple of photos taken earlier this year using Pixinsight. Great program, but it will probably take me a thousand years to learn all it can do. I only scratched the surface and the results compared to before are amazing. The photo of the Andromeda Galaxy was a composite of 100X20 second exposures taken at Mahogany Hammock in February. The galaxy was low on the horizon and there were clouds moving through, and yet it came out OK. The region of the Lagoon Nebula near the central region of the Milky Was was taken from my driveway where the sky is OK but not super dark, same number of images as Andromeda. Can't wait to get out to a dark site again and put more effort into the images. If I can learn more of Pixinsight the results could be promising. The camera is a Nikon D7200 with a NIkkor 80-400mm lens piggyback on a Meade 8" SCT.
I still haven't figured out how to superimpose a part of a photo over a part of another one. (haven't worked at it that hard, either) For example, a friend once took a shot of me shoveling snow and added a reclining Polar Bear to it. Made a neat composition but I've never been able to make it work.