After exporting in fcx all the video files with photo-jpeg codec somehow become much darker in shadows.
Even in old projects now I have different color space after switching between proxy and original media.
Problem appeared with files shot on canon mark IV in 4k.
All files from other formats are ok, same as they look in finder, even 1080p from the same camera. (actually 1080p are shot in h264 with 1-1-1 gamma and 4k are photo-jpeg with 1-1-6 gamma).
Nothing helped – changing color space override in fcx, reinstalling the app etc, just a stupid way to convert source files in prores and import again.