I thought I recognised the look of the images. I was also surprised by the size of the files (quite small) and even looked at the FITS Header; all of which are pointing to it only being an 8-bit image.
For some reason, AstroImager is only saving them as 8-bit and not 16-bit files. Think of it as being the difference between a JPEG and RAW camera file. Are all of the FITS files the same size?
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