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Strange artefact  


Hydrogen Atom Customer
Joined: 2 years ago
Posts: 1
September 21, 2021 19:32  

Hi. I am an absolute beginner with APP but have been processing data for a few years now with Pi. I really like the look of APP for pre-processing and I want to get into mosaics.

I got data last night from M31. I am using an Esprit 100 with a 294MC camera driven by an iOptrom GEM 45.

The subs are 120 second with a LPro filter (full moon and I have bortle 8 skies). I use EKOS for capture and have captured 25 subs for each corner in a 2x2 matrix. I have Darks, Flats and DarkFlats.

When I integrate (default settings) I get this. Left are 25 integrated subs and right is an individual sub that has only been debayered and stretched.

Screenshot 2021 09 21 at 19.26.48

This is a close up of the artefact in the middle of the integrated version.

Screenshot 2021 09 21 at 19.29.49

Any idea how I managed this?


I have just stepped through and the calibration goes fine but its after the registration that the artefact appears.

I just updated to the latest Beta and now its fine! Let's see if I can get this mosaic done now.


This topic was modified 1 month ago 2 times by Rishi Garrod

Universe Admin
Joined: 4 years ago
Posts: 3861
September 22, 2021 13:09  

Switch off dynamic distortion correction. Likely your data doesn't need it and sometimes, in such a case, the algorithm goes haywire.