Gamut

Overview

The gamut (German: color space or color range) is the set of all colors that a device can capture or display. In the CIE standard color diagram, a gamut is described by a triangle whose vertices mark the three primary colors (red, green, blue). The further apart the vertices are, the larger the triangle and thus the representable color range. No technical gamut encompasses the entire color range visible to the human eye.

In film and TV production, a distinction must be made between two types: the capture gamut of the camera (which colors the sensor processes internally) and the output gamut of the playback device (which colors a monitor or projector displays). A color management workflow transfers image data from the camera-native gamut through the editing and grading space to the final delivery gamut.

Standard Gamuts in Playback

Several standardized color spaces have been established for output. They differ primarily in the position of their primary colors and thus in the size of the covered range:

In terms of range, the following applies: Rec. 2020 is larger than DCI-P3, and DCI-P3 is significantly larger than Rec. 709. Rec. 709 remains the smallest of the three and the common standard for classic HD material.

Camera-Native and Working Gamuts

Professional cameras capture images in manufacturer-specific, intentionally wide color spaces to retain as much color information as possible for post-production. These "wide-gamut" spaces are usually combined with a logarithmic tone curve:

• ARRI Wide Gamut (with Log C) – ARRI ALEXA/AMIRA family
• REDWideGamutRGB (with Log3G10) – RED cameras, standardized across models
• Sony S-Gamut3 or S-Gamut3.Cine (with S-Log3)
• Blackmagic Wide Gamut (with Blackmagic Film)

The ACES framework serves as a cross-manufacturer reference: ACES2065-1 uses the very wide AP0 primaries (encompassing the entire visible spectrum and more), while the grading-friendly spaces ACEScg and ACEScct work with the slightly narrower AP1 primaries to avoid numerical instabilities during grading.

Significance for Lighting and Set

The gamut is not just a post-production topic. Modern, highly saturated LED lights and colored practicals can produce colors that reach or exceed the boundaries of the camera's gamut – especially in the highly saturated blue and magenta areas. If a light color is outside the capturable range, the affected color channel can "clip," leading to a loss of detail and color separation. Current color engines (e.g., ARRI's ACE approach) therefore rely on gamut compression to fold such extreme light colors back into the representable range. For gaffers and DITs on set, this means: very saturated LED colors should be checked for clipping on the camera monitor and in the scopes.