Flats being overapp...
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Flats being overapplied

Hydrogen Atom Customer
Joined: 3 months ago
Posts: 1
Topic starter  


This is my first post here. I am currently on the trial version but will buy APP when the trial expires. It's a good piece of software with some pretty neat tools. 

However, I've never been able to correctly apply my flats in APP. If I use the exact same flats and lights and stack them in a different program like Pixinsight or DSS, everything goes smoothly and I have zero vignetting left. So it's not bad flats or anything, it must be a software/user error issue.

In APP I get really weird results. Almost as if my flats are inverted, so I also tried inverting a master flat in Pix and then integrating that in APP. Did not work. 

I am really desparate to solve this issue. Any help is welcome.

flats applied

 Here is the l-calibrated view.


Flats were 3-4 seconds each. 3,6s for this particular filter set (SII). The problem occurs on all three sets though. I did not take dark flats but I have bias and darks. Camera is a 294mm

This topic was modified 3 months ago 4 times by Ben Dinkelbach

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Universe Admin
Joined: 6 years ago
Posts: 5218

Would you be able to upload 10 flats, 10 bias, 10 darks and 10 lights for me to check? It may still be an issue in the data so would be nice to see what's going on.

Brown Dwarf Customer
Joined: 2 years ago
Posts: 9

Not meaning to hijack this thread (so feel free to delete if this is irrelevant), but Vincent, could this be related to my issue at https://www.astropixelprocessor.com/community/main-forum/creating-a-master-dark-flat-what-am-i-doing-wrong/#post-25977 (i.e. the master flats Ben is making in APP (as opposed to his processing in other software) have too high an ADU in some way?)

Universe Admin
Joined: 6 years ago
Posts: 5218

I can't tell to be honest, I do know it's never a good idea to mix programs for processing calibration files with lights. The way calibration is done does differ sometimes, not usually in the way you're experiencing though.