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ASI1600MM-C noise
A question about the ASI1600MM-C's noise. Attached is a blown up (3:1) crop of a highly stretched single sub of 30s duration (in 47 Tuc). There are numerous black dots in there, typically in the lower signal areas.
Though they pretty much disappear in cosmetic correction and stacking in PI, I'm trying to understand if they are an issue. They are not dead pixels, as they change location from frame to frame. They seem to be very big outliers in the distribution though, as the overall noise level is relatively low.
A similar (probably same) effect I've noticed with biases e.g. mean ADU value is say at 300 with a std dev of about 30 say, and yet there are many points with values down at 16. Seems like there's a very long tail on the noise distribution. The rejection maps in Image Integration in PI have a lot of data in them, whereas for my old QHY8 they were essentially black.
Is this normal for this camera? Or has mine got some issues?
Comments appreciated.
Paul
PS If it makes any difference, this is at unity gain (and offset the default of 21) and -15C cooler temp.
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