The image grader has nothing to do with Nikon. A few notes that may lend
insight to the issue you’re seeing:
- The image grader only works on unsigned 16-bit, single plane FITS
images (the kind that SGPro produces). You can have SGPro produce these
type of FITS images with DSLRs
- The image grader does not work with any type of RAW format (either
Canon or Nikon)
- The image grader will not work on debayered FITS images if they use
the 3 plane storage method, if your debayered FITS files still use the
single plane method, the image grader will just grade the blue channel.
- The image grader will not work if you have opened the image and
resaved it with a different bit depth (i.e. 32 bit).