Help with gradient in the final mosaic

John Murphy PhotometricMosaic (PMM) Mosaic M31 Galaxy Deep Sky
3 replies•102 views
Emilio Frangella avatar
Emilio Frangella avatar
I am processing a two panel mosaic of Andromeda. I have an issue with PMM were the target image presents a dark gradient towards the center (see screnshot)

I have tried adjusting the various gradient parameters (especially the ones for the target image) without much success. I have had this with the L filter, but i solved it by carefully aligning the black points before stitching it together - now i have it also with the Red filter but aligning the blackpoints doesnt help. Does anyone have tips on how to solve this?
andrea tasselli avatar
andrea tasselli avatar
Have you tried the standard method?
Médéric Hébert avatar
Médéric Hébert avatar
Any chance you got some lights in your darks? It gives results like that.
Wei-Hao Wang avatar
Wei-Hao Wang avatar
If this is a two-panel mosaic, the overlap seems very small.  This can always be a source of various kinds of problems.

In PMM, personally I found the most impactful parameters to be scale and smoothness.  If you can show the various graphs that PMM generates, people here can help better on diagnosing the problems.
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