Color grading is also subjective and digital tools now allow the
director and creative team to achieve any look they like.

The color grade also includes setting light levels. Projection
systems and screen light levels (measured in foot–Lamberts, fL) vary
considerably. You will end up with multiple deliverables, depending on the
film’s destination, and this is the time to get those versions right, while all
the material is live in the online system.  
When creating grades for both 4.5 fL (standard digital cinema)
and 10 fL (laser digital cinema), it is advisable to grade for your lowest
level first, then apply a global adjustment later for the brighter version. If
you really can’t afford to grade both versions individually (and it is
strongly recommended you do), this order will offer the least compromised
result.
Until recently DCI-P3 Colour gamut was the target. However, wider
colour gamuts, such as REC 2020 are now becoming popular and some projectors
(Christie) can reproduce some or all of the Rec 2020 colour gamut.