Transfer function

A transfer function is how a color space encodes brightness: the mapping between the numbers stored in a file and the light a display emits. Standard displays use a fixed power curve — Rec.709 is mastered to roughly gamma 2.4, sRGB to about gamma 2.2. A log transfer function is a special, flat curve that packs a huge brightness range into the file for latitude, which is why log looks milky until it’s normalized. It is one of the two independent halves of a color space; the other is the gamut.

First used in: 2.1 · Color spaces & camera log