Canon EOS-1D X Mark III DSLR Camera (Body Only) - Manual (Page 143)

Color Space
Adobe RGB
The range of reproducible colors is called the “color space.” For normal shooting, sRGB is
recommended.
1.
Select [ : Color space].
2.
Set a color space option.
Select [ sRGB ] or [ Adobe RGB ], then press < >.
Adobe RGB
This color space is mainly used for commercial printing and other professional applications.
Recommended when using equipment such as Adobe RGB-compatible monitors or DCF 2.0
(Exif 2.21 or later) compatible printers.
Note
File names of still photos shot in the Adobe RGB color space begin with “_”.
The ICC profile is not appended. For the descriptions about the ICC profile, refer to
the Digital Photo Professional Instruction Manual (EOS software).
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