There's a good one by Rogelio Andreo about PixInsight and also deep sky imaging.
https://www.deepskycolors.com/books/...ng-pixinsight/
There's also a book which is a collection of various top imagers like Rob Gendler about how to process various types of images. Title is something like astrophotography by the masters.
https://www.amazon.com.au/dp/0760335...erred_us_au_au
That is probably the best resource and not limited to DSLR. You can do a lot with DSLRs and there are plenty of awesome DSLR images but at the end of the day its mono CCDs that produce the highest resolution and depth of image.
Greg.