I also update my darks a couple of times a year. I take them using a fridge to reach the desired temperature, I usually take them every few degrees. I image at a fixed gain (50) and exposure (I use 12 seconds as I find that is long enough to pick up faint stars and yet not produce noticeable star trails), so I only need to match the dark to the camera temperature (I store the temperature in the Dark Frame Name, so it is easy to search on and find the one closest to the image temperature). I have ImageMagick loaded on the Rpi and run command line routines like "level" and "brightness-contrast" to sort of stretch the image. All of the image storing and processing routines are run in shell scripts that are called from subroutines in the main capture.cpp (C++) program.

I have thought about changing the camera (ZWO ASI 120MC) parameters when the moon is out, but I have not found camera settings that deal with a bright moon and can still image stars. I will look into how you are dealing with this. I also like the idea of determining sky brightness and logging this with the AP images I take with my telescope, on the same night. It may help set my expectations when I process the images.

I have had a lot of fun with the AllSky camera project over the past 3 years, it is probably time I did some updating of the program and equipment. I am on my second Rpi as the USB ports on the first one stopped working after about 2 years outside (the Rpi and camera are in a water tight junction box container with the usual plastic dome.)

So thanks for providing an alternative approach.

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