Maybe this request could be in the beginners section, but it's a bit techo.
3 images cropped from the same frame (M8: 1 x 5 minutes and 1 x 6 minutes) calibrated with a master dark and master bias in Pixinsight - no flats (still working on producing a reliable set).
The original image was colour calibrated and background neutralised in Pixinsight.
I've boxed the areas in question, and other than obvious alignment issues, there are;
1. dark pixels adjacent to the brighter stars,
2. in the small image there is a block of red pixels, and on the left a single bluish pixel.
3. what appears to be either cloud or reflection nebula producing a bluish tinge...
I'm not sure that these issues/artifacts would show up with more data (possibly), but conveniently they show up here -
Many thanks
Rowland.