---
title: "Linear Light"
url: https://postproduction.studio/en/glossary/linear-light
language: en
description: "Linear light is the encoding model in which signal values are directly proportional to actual scene luminance — twice the recorded value means twice the..."
updated: 2026-10-25
---

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# Linear Light

Linear light is the encoding model in which signal values are directly proportional to actual scene luminance — twice the recorded value means twice the actual light from the scene. This is the natural physical relationship and the encoding used in scene-referred VFX work, particularly compositing and CG rendering. The OpenEXR format and ACEScg working space are both linear-light. In linear-light data, light addition, subtraction, multiplication and other compositing operations behave correctly — a 50% gray on top of a 50% gray gives twice the light value (a logical brightening), whereas in gamma-encoded data the math produces incorrect visual results. Linear light is, however, perceptually inefficient: human vision is highly nonlinear (we perceive much finer detail in shadows than in highlights of equal luminance ratio), so a linear encoding wastes a lot of code values in highlights and starves the shadows of precision. Display formats therefore apply a transfer function (gamma 2.4 for Rec.709, PQ for HDR) to encode for transmission efficiency, then linearize for math operations, then re-encode for display. The VFX pipeline typically does all heavy lifting in linear-light EXR files at 16-bit half-float precision, where math is well-behaved and there is no risk of banding from precision loss. The Filmic Blender and Academy Color Encoding System both rely on linear-light working spaces.

Color Science, VFXVFX Supervisor, Compositor, ColoristVFX, Pipeline

## Related terms

[Gamma](https://postproduction.studio/en/glossary/gamma)[ACES (Academy Color Encoding System)](https://postproduction.studio/en/glossary/aces-academy-color-encoding-system)[Logarithmic (Log) Curve](https://postproduction.studio/en/glossary/logarithmic-log-curve)

Color gamuts plotted on the CIE 1931 chromaticity diagram. Wider gamut = more reproducible colors.