What is 'really raw' ?
Canon CR2 and Nikon NEF are actually a sort of modified TIFF files.
And astro modding is not needed anymore for more modern cameras. I have an EOS 6 NOT modded (original version, the Mk2 and the just released Mk3, actually called EOS R) and can make perfect photos of Halpha red nebulas.
When I stack CR2's with DSS or Siril, I can open the resulting TIFF with Adobe RAW and do all the fine tuning as if it were a CR2.
|