Either enable in camera long exposure noise reduction and in camera high ISO noise reduction, in which case the camera will take a dark after each exposure, or take some darks yourself at the end of the imaging session, and stack them with your normal subs[ assuming that you are using RAW, as you cannot use darks with JPEGs.]
raymo
Last edited by raymo; 12-01-2019 at 11:50 PM.
Reason: more text