Lab and RGB. But we recommend Lab because in this mode you can get more predictable results in some cases.
FireGrade currently supports all x64 versions: CS4 (only for Windows), CS5, CS5.1, CS6, CC, CC2014, CC2015, CC2015.5, CC2017.
32-bit versions are not supported.
Windows 7 x64, Windows 8 x64, Windows 8.1 x64, Windows 10 x64.
Mac OS X 10.8.5 and higher.
1920x1080 or higher.
8 and 16 bits per channel.
Yes in Lab color mode. You can view results of correction in the plugin preview window with target color space and profile.
This is a cylindrical representation of Lab color space.
Read more about Lab and Lch in Wikipedia article.
Because Lab color space has larger gamut than RGB or CMYK.
Read more about gamuts in Wikipedia article.
Because of rounding in conversion routines from integral to floating point numbers and vice versa.
Because we use our own representation for histograms that is slightly more informative.