I'm working my way through the wonderful 12-part YouTube tutorial, which is making PI comprehensible for the first time. I have a series of subs of M51 that I took a few years ago. These were saved as JPEG files because I forgot to make my Nikon DSLR save the pictures as raw files. Should I convert the JPEGs to some other format before I start subtracting dark frames, extracting background, aligning, stacking, and so on? Do I need to de-Beyer these files if they're already JPEG? I can't tell from the tutorial because he starts from a raw format.