Hello, all.
I have a new troublesome blue/purplish artifact that is showing up next to the brightest stars in my stacked images of NGC 2170, the Angel Nebula.
I'm using a Celestron EdgeHD 800; ASI2600 MC-P; Celestron OAG with ASI174 Mini; and AM5.
This is the first time I've seen this problem.
I use Siril to do the stacking and the artifacts are appearing in the basic stacked image viewed through AutoStretch.
Drizzle seems to make it worse.
Simple stacking using the ASI Deep Sky stacking app seems to make it far less obvious or even non-existent.
What is the cause and solution?
Many thanks in advance, as I'm about to set off on a two-week trip to clear skies and would like to know I can fix this.