I'm a keen astrophotographer with several scopes and a Dome. I image mainly deep sky objects and also contibute to the AAVSO variable stars program. I also participate in several astro clubs and like to spread the word about this fascinating hobby.

Yes

You can recover this problem by creating a synthetic flat that will eliminate the blotches and doughnuts. I've had this when dew overcame my heaters or I reframed/rotated the camera and forgot to retake the flats.

hi kat thanks - blobbed out on the stars though. Tricky getting the colours right.