LUT Management for Video Teams

A LUT is a mathematical transformation that maps input color values to output color values. There are two main types: 1D LUTs, which affect each color channel independently (essentially a curves adjustment), and 3D LUTs, which can remap any input color to any output color, enabling more complex transformations like color space conversions and creative looks.

Technical LUTs serve a specific conversion purpose, such as converting from LOG to Rec. 709 or from camera-specific color science to a standard color space. These LUTs are typically provided by camera manufacturers or color science experts and should be used precisely as intended. Applying a technical LUT designed for one camera log to footage from a different camera produces incorrect results.

Creative LUTs, sometimes called "look" LUTs, apply a specific aesthetic treatment: a film emulation, a color grade style, or a branded look. These are created by colorists and can be applied as a starting point for grading. Unlike technical LUTs, creative LUTs are subjective and may need adjustment per project or per shot.

Establish a centralized, version-controlled LUT library that all team members can access. Organize LUTs in a clear folder structure: separate technical LUTs from creative LUTs, group technical LUTs by camera system, and group creative LUTs by project or brand. Include descriptive names and documentation so anyone can find the right LUT without guessing.

Naming conventions prevent confusion. Include the camera system, color space conversion, version, and date in the LUT filename. For example, "ARRI_LogC4_to_Rec709_v2_2024-01.cube" is much more useful than "ARRI_grade.cube." Consistent naming also makes it easy to identify outdated LUTs that should be replaced.

Access control matters for team LUT libraries. Colorists should be able to add and update LUTs, while editors and other team members should have read-only access. This prevents accidental modification of critical LUTs and ensures the colorist maintains creative control over the look development process.

On set, LUTs are used in monitors and video village to provide a preview of the intended final look on LOG or RAW footage. This allows the director, cinematographer, and client to evaluate the creative direction in real time. The on-set LUT must match the LUT used in post-production to ensure continuity between what was approved on set and what the colorist delivers.

In editorial, a viewing LUT applied to the timeline lets the editor make creative decisions based on the intended look rather than flat LOG footage. This LUT should be non-destructive, meaning it affects the display only and does not alter the underlying media. When the project moves to color grading, the viewing LUT is replaced by the colorist actual grade.

During review, ensure that reviewers see the content with the correct LUT applied. A common source of confusion occurs when footage is sent for review without a LUT, and the reviewer sees flat, desaturated LOG footage and assumes the color is wrong. RecReview and similar review platforms can display content with viewer-appropriate processing applied, so reviewers see the intended look regardless of the underlying media format.

The most common mistake is applying the wrong technical LUT. Using an ARRI LogC LUT on Sony S-Log3 footage will produce incorrect colors. Always verify the source color space of your footage and select the matching LUT. Camera metadata embedded in the file or documented in the camera report identifies the correct color science.

Stacking LUTs incorrectly is another frequent error. If a timeline already has a LOG-to-Rec. 709 conversion LUT applied and a creative LUT designed for Rec. 709 input is added on top, the result is correct. But if the creative LUT expects LOG input and is applied after the conversion LUT, the result is doubly converted and incorrect. Understand the input and output color space of each LUT in your chain.

LUT precision matters. Most professional LUTs are 3D LUTs with 33 or 65 grid points in the .cube format. Lower-resolution LUTs (17 points) may introduce visible banding or inaccuracies in critical color ranges. When creating or exporting LUTs, use at least 33 points for general use and 65 points for maximum accuracy.