Camera: QHY183M.
Some things to note:
This camera produces significant amp glow in the Light Frames, which can mostly be removed by:
1. Not using bias frames
2. Appling dark frames.
Also, there are non-random horizontal bands that can be seen in the darker regions like the lower left quadrant. Dark frames and flat frames do not have any effect on the banding, so I would guess it has something to do with the sensor itself. Mostly noticeable when images are stretched.
*Update.
Using
https://astronomy.tools/calculators/ccd_suitability, shows the camera is slightly oversampling in Bin1x1, but has ideal pixel size in Bin2x2 for current sky conditions/telescope properties. The result is the horizontal banding is gone in subsequent tests (not shown).
-First picture stretched to show horizontal banding in lower left quadrant.
-Second picture is processed using above mentioned technique to minimize horizontal banding and amp glow.
-Third picture is Light Frames only to show amp glow on right side.
Image details:
20 Light Frames @ -20C for 420s
20 Dark Frames @ -20C for 420s
20 Flat Frames (calibrated for image)
20 Bias Frames (converted Dark Flat Frames with Deep Sky Stacker)
Gain 11
Offset 30
USB Traffic 0 (USB 3 connection)
Brian.
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