The problem seems that the light pollution either isn't actual light pollution, or it created a weird pattern maybe due to internal reflections? It should normally be a gradient, which means it's gradual and not this spotty. You can see that I tried to make a correction model on the jpeg above (not ideal to do like that but ok) and it's not a normal gradient, which makes it pretty hard to correct.

@vincent-mod

🤔 Wierd, it doesn't show as much on the tiff (I said fit above and I meant tiff)

@vincent-mod

ok so this is as good as i could get to best show it, its a screenshot of the 45mb tiff, I like the star colours, they've come out better than expected but what you cant see is the grainyness.

Posted by: @tonymacc

Wierd, it doesn't show as much on the tiff (I said fit above and I meant tiff)

I always over-stretch and over-saturate to better see the issue in the background. And then I place my boxes, does help a lot. The grainyness will likely be left over because of the uneven background and maybe not enough data, getting that better usually requires darkers skies and more data.