Doug
I think these are just hot pixels showing the total drift over the course of the exposure.
Sigma clip stacking removes them, but averaging or adding leaves them in.
You could try stacking all your images withoug aligning them - I think you will find the hot pixels strong and all your stars take that shape instead.
Dark frames will help and the sigma clip stacking as well.
cheers
Phil
Quote:
Originally Posted by dugnsuz
Hello all,
Advice needed...
Recently noticed some weird things after using my new 400mm f5.6L lens.
Stacked/Combined images seem to have some strange 'wiggly worm' artefact throughout the image - it's not present on ANY of the individual subs either...checked them all.
Below images...
Left: Stacked/Combined using Adaptive Add (problem obvious when stacked using Average too)
Artefacts circled!
Right: same data combined using Sigma Average
Stacked in Images Plus.
Any ideas as to what's going on?
Doug  |