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Hey, Rick,
thanks so much for uploading your files, it's been invaluable.
With that as a guide I've managed to trouble-shoot a number of issues and my data is looking similar to yours. I've also learned out how to retrofit trend lines and derive the formulae in order to determine intermediate values, which is handy.
But, I'm a bit stuck with the Dark current.
According to Craig Stark, if you look at the mean for a bias frame and subtract that value from your darks, you will be left with the dark current, which should increase linearly the longer you expose.
So at any one gain setting the determining factor is time. More time = more dark current.
I'm getting a non-linear relationship. Seemingly at all gain levels, increasing exposure yields less dark current.
I can't figure out what I'm doing wrong. I integrated 250 Bias frames at the same temperature, gain, offset and exposure settings as the darks.
Hmmm.
I've included the data below. It's in 12bit values because I prefer to convert at the end.
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