Long story short: As part of a failed attempt to clean some dust off my sensor, the glass in front of my camera's sensor got spots on it and my flats failed. I can't figure out why my flats failed, but this happens to me about 10% of the time (oddly, I'll be working on two images at the same time and in one the flats will work perfectly and the other, things will have rotated just a tad). I managed to fix the glass and my session from last night looks fine (and my flats worked anyway), but my session from the February 8 looks terrible. I tried combining the two sessions but I couldn't fix the reflections of the spots from the first session.
I'm wondering if someone who works with PixInsight is aware of a simple process or script for smoothing out the background so that I won't have to trash 5.5 hours of data. If no such process exists (or if it takes time), then I'd prefer trash the data rather than take up someone else's time.
I'm attaching a very compressed JPEG to give an idea of what happened with this image. The original stack can be downloaded here: https://drive.google...k4p-2e9DiVGdyy