Aaargh!  I've spent two days trying to work out why I couldn't get images from my latest night's session to calibrate properly.  In the end I had to look at the FITS header and eventually saw that the images had been taken with an offset of 10 rather than the default of 50 that my camera has used for the past 3 years.  Has anyone else had this issue recently?  I didn't change any settings in APT or ASCOM.

I didn't really want to re-take all my darks to troubleshoot this, so instead I used pixelmath on the darks taken at 50 offset to try and create some pseudo-darks that would work with these new images taken at offset 10. 

I used "$T-(40/4096)" in Pixelmath to remove the extra offset from my original darks, which given that my camera is 12 bit seemed like the right solution.  Any thoughts would be appreciated, however it does seem to have worked.

Note to self: set the offset manually in APT rather than relying on the default from the driver.
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