I'm running an unguided C8 HyperStar V4 on an AVX mount with an ASI 294MC pro (cooled) camera, which I switched from the 183MC (non-cooled). With the 183MC I had strong light pollution gradients which I could fix with AstroPixelProcessor, but now that I have the 294MC pro, my images are plagued with artifact, the worst of which is a diffuse paintbrush-like background artifact (walking noise?). I've been working on my setup and technique based on advice given here but I just can't figure out what I'm doing wrong. I would really love for any feedback on this FITS stack. I've hit one of those ruts where I just can't move forward no matter what I think of fixing.
Things I've done to optimize image quality:
-Tight polar alignment, tight focus with Bhatinov mask
-Remove Optolong L-Pro filter (now shooting with no filter, although I just received a UV/IR cut filter)
-Reduce sub exposure time (now 10s)
-Lengthen flat exposure time to accommodate non-linear response of 294MC pro (3s with dimmed LED light panel); ADU is 19k
-Incorporated dark flats (3s to match flats)
-Stopped using bias frames
For this image:
Reducer: HyperStar (390 mm, f2)
Camera: ASI 294MC pro @ -10C, gain: 0
Capture software: ASI Air Pro
Light frames: 369 x 10 s (1 hour)
Dark frames: 20 x 10s
Flat frames: 20 x 3s
Dark flat frames: 20 x 3s
Sky: Bortle 7/8
I'm very frustrated as I've done my best to lock down the fundamentals of image acquisition. Any and all help is greatly appreciated.
Edited by ts298, 18 June 2021 - 10:24 PM.