I am using both programs to try and solve an issue with tilt and curvature I have in my system but both software packages are giving me very different results.
ASTAP says I have 25% tilt whereas CCD says its around 5%.
Sorry I don't know the answer to your question, but I'm gonna throw in a 3rd option which to me is easier to understand/visualise and therefore, fix.
I haven't used ASTAP but did buy CCDi which to me was a little tedious use. If you use N.I.N.A., its aberration inspector, to me, is easier to understand, and therefore easier to fix (if you do have any tilt or BF issues).
I've attached the screenshots here. They're pretty much self-explanatory. You could try NINA and see how it compares with ASTAP/CCDi.
Thanks for showing that- I use astap, but will try NINA. Can I install it in my desktop and have it analyse images, or does it need to connect to the telescope and focuser?
I believe it has to be done in realtime and it actually use the focus curve shifts - so it'll be taking many images to analyse it. I didn't take a screenshot of it so I'd have to quote someone else's from CN:
