I am working on a project, that will last for months. So I will for certain gather lights that will require different sets of calibration frames, because I may shift the camera, or new dust donoughts may show up. Which will all require new flats.
To be able to stack sets of lights that is ascociated to different calibration frames, one will have to generate calibrated lights from each session, and finally process (stack) all the calibrated lights to reduce the overall noice.
I have made a short instruction video of how to do this with Astroart, it can be found here:
https://youtu.be/j4L7sfVPLcA
