Problem with the contrast function

[Stefan]

Hello,
When I use the Contrastfuntion I have a edge arround my picture:

[Stefan]

Hello,
whehn I take the Dark Anomaly Filter from 1 Pixel to 15 or 30 Pixel, it is ok.

[Stefan]

Hello Again,
When I first Develop 90%,I have no Edge.
When I take 95%, I have Edge.

Hmm....

[admin]

Hi Stefan,

The problem seems to be a 1-pixel border of darker pixels, similar to stacking artefacts.
Stacking artefacts and other data that is not 'real' celestial detail, such as dead pixels or dust donuts, can cause all sorts of problems.
In this case, the Contrast module is backing off in the area where it detects the strange border/stacking artefacts, because it thinks it is real detail that needs to be preserved.

Can you tell me if this border present in your source data? Or do you think StarTools has created this 1-pixel border?