Color without mystique
What is a LUT?
A look-up table, or LUT, maps input color values to new output values. In video and photography, that mapping can normalize camera footage, create a visual look, or do both.
Why it is a cube
A 3D LUT uses red, green, and blue as three coordinates. Each point inside the cube stores a replacement RGB color. Real pixels fall between stored points, so software interpolates—commonly with trilinear or tetrahedral math.
Technical and creative LUTs
Technical LUTs convert between known encodings, such as a camera log curve and a display space. Creative LUTs reshape contrast and color to establish a look. A technical transform has a strict expected input; a creative LUT also behaves best when its intended input is known.
Why the same LUT looks different
Exposure, white balance, camera gamut, gamma, legal versus full range, timeline color management, interpolation, HDR tone mapping, and display calibration all affect the result. A LUT is deterministic, but the pixels entering it often are not in the state its creator expected.