I've been successfully using a modified (baader-bcf) Canon 250D for the past 2 years w/o particular issues, however, recently a very strong vignetting on 1 side of the image started to appear. I ruled out the optics, as it manifests with all my scopes and lenses, even without a lens attached. It also doesn't seem to have anything to do with exposure time or temperature either. It happens on all ISO levels as well.
Again, it only started appearing recently, this winter. I never did flats with this setup as it didn't seem necessary until now.
Attached is a skyflat (1/4000 exposure, iso800) to demonstrate the issue:
And how it manifests when imaging:
What puzzles me the most is that it is changing sides on the image, doesnt seem to be the same side always. For example it is the top side of the image, even if i rotate the camera 180 degrees (with auto-rotation turned off)...
Did anyone else experience such issues with this sensor (or any other camera as a matter of fact), or have any idea what could this be and how to fix it?
Is the sensor going toast? Tbh i've been using it a lot in out-of-spec temperatures in winter night sessions.
Thanks!
Attila
