Recently I came by the AstroImageJ (AIJ) software. I was looking for something that I could write my own functions in, as I did 20 years ago in Matlab. AIJ looks very promissing and I have now put together my first macros that let me batch load Canon EOS CR2 files and process them.
It take advantages of CR2 files overscan region to get an emulation of dark and bias levels. Because the image and dark comes from the same image they allways has a matched temperature and darkcurrent. But it's not induvidual pixel values it's an average value. It has some limtiations but if your camera is of late low noise type, especially the static pattern and you take your images with dithering technique it will works very well, at least in my case.
I have already before I started to do experiment with AIJ started to use dithering technique to get rid of those time consuming dark and bias images. Now I can refine this method and get even better result.
The macro I have put togehter also demosaic the cr2 file to rggb files and after that handle it more like rgb files from a monocrome camera.
Does it sound exiting?
See my tutorial here:
I'm in the beginning of AIJ so expect my macros have some bugs and use them by your own risk, have backup of your files!
I had or have the Canon EOS 350D, 5D and 6D which I have tested my macro on with positive result.
I hope you find it useful or at least interesting !
What's even more positive, AstroImageJ is free to download !
Follow the instructions in my tutorial where to download and how to install and setup.