Quote:
Originally Posted by Atmos
Okay, done a little bit of testing. As it was mentioned that the back end of the histogram was being clipped I tried processing some of the raw data files, had the thought while I was at work today that it may have been caused by the calibration files doing something they're not supposed to do.
Hasn't made any difference so I am assuming that the problem is at the point of taking the images.
I probably should have checked and not gone from memory, I have Gain at 26% and Offset at 102 when at normal readout speed. When running at high readout I run at Offset of 75 with the same gain. Guess I'll have to do some more testing, maybe I am clipping it a bit :/
EDIT:
Decided to mathematically calculate the what number should be. At a gain of 26% I have an e/ADU of 0.491. With a full well of ~25,500 and a full ADU of 65535 I should have a gain of 0.3891. Ultimately this corresponds to a gain of 20.6%. I originally calculated 21% and then added 5% to take off the non-linear aspect of the CCD.
So, from what I can tell the best I can do is drop the Gain down to 21% which will increase the dynamic range a bit but it shouldn't be having any effect on the data being obtained. Back to where I started again.
Any thoughts anyone?
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OK - so are your files correct & ready to process or
did the filter not change?