Pixel pox after stacking

[cytan]

Hi Han,
In my last two sessions, I noticed that there were green pixel pox's in my final stacked image. The one that I have attached was particularly bad:

 sigma_2.5 pixel pox.jpg

I "cured" it by reducing the sigma factor in sigma clip average from 2.5 to 0.5. Result is seen in:

sigma_0.5.jpg

I'm using ASTAP 2026.5.19, but I've checked that this problem was there even in ASTAP 2026.01.15. Note: The pox pixels are still there even if I don't use darks.

Unfortunately, SIRIL is refusing to stack this particular set of images to show that it is an ASTAP stacking effect. However, I used another set of images and the result that was stacked with ASTAP also shows pox pixels but a lot lesser in extent. Stacking this set in SIRIL does not produce pox pixels.

Although, the problem seems to have been cured by lowering the sigma from 2.5 to 0.5, is this the right solution?

cytan