Earlier this month, in combination with the new moon we had three consecutive nights of ok kind of weather for astrophotography. Basically, the sky was cloudless for more than half the night, but clarity wasn’t the best. So I decided to shoot M45, since this is a target that I think is best done with at most an IR/Cut filter, and no moon. What happened was that when the clouds weren’t there I got good subs, but when there were clouds, they guiding fell apart and the sub quality tanked. You can see an example of the guiding below.
This caused some issues with the stacking, which is one of the reasons why I’m posting nearly two weeks after completing. Right now we have a bit over 12 hours of darkness. Unfortunately, M45 rises behind a rather tall tree for me, so I can’t start shooting until nearly 45 degrees above the horizon. That, combined with the clouds is why it took me 3 nights to collect 12 hours of usable data. Even worse, I struggled to get reliable automated rejection on the bad subs in Siril, and ended up hunting through them by hand to delete the bad ones. Fortunately, the bad subs tended to be clustered pretty well, so it wasn’t too bad.
Once I had a good stack, I used a very basic workflow. Photometric Color Calibration:
GraXpert backround extraction.
StarNet star removal and Starless GHS stretch:
Then a recombination and some very minor touchup in GIMP for the final product.
Sweetman Astrophotography 
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