Hi Tim. I think that maybe it is a design issue that carries over from the sensor's days in a terrestrial camera.
From what I can tell, looks like the camera erases hot pixels when they get above about 8000ADU. There are occasional pixels that are near the threshold and can disappear on either the dark or the light - but not necessarily both. Then you get a few pixels that are not corrected by the dark cal.
I find that dither plus minmax rejection when stacking cleans them up OK. Bad pixel rejection also works, but only with darks that are taken at a shorter exposure than the lights - just to make sure that no hot pixels have been "disappeared" in the darks, but not the lights.
Sam from ZWO confirmed that the camera/software implements a bad pixel rejection process and offered to check with his software person to see if there was a solution to the odd hot pixel that goes missing in action - didn't hear any more, so guess not. In any event, it is not a deal breaker. cheers Ray
Last edited by Shiraz; 21-08-2017 at 10:06 PM.
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