I just tried StarAlignment for the first time, and I am amazed at the results
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Here's the background, if you are interested.
20 x 180s each of R, G, and B, imaged on 2 nights.
Canon 200mm lens at f2.8, 6.8 micron pixels, considerably undersampled.
From one channel to the next, I have issues with rotation, field curvature, varying FWHM, star aspect ratio, and possibly others.
I tried several varieties of alignment in MaxIm which have worked well for me on other data sets, but not this one.
I had already given up on trying to align images from the above equipment in any other s/w I own.