How a LUT works in plain numbers
Log camera footage is recorded flat so the file keeps as much highlight and shadow detail as possible. On a normal monitor it looks gray and washed out. A LUT is a table: for each input value, it lists an output value. A 3D LUT stored as a 33-point .cube file samples 33 steps for each of red, green, and blue, which is 33 x 33 x 33 = 35,937 color entries. Values that fall between those points are interpolated.
Take one pixel of skin tone recorded in log at red 0.48, green 0.40, blue 0.36 (on a 0 to 1 scale). A show LUT might output red 0.62, green 0.47, blue 0.39: more contrast, a little warmer. Every pixel in the frame goes through the same table, which is why a LUT is fast enough to run live on a camera monitor.
The LUT's path through a production
In prep, the director of photography shoots tests and builds a show LUT with a colorist. The file then travels:
| Stage | Who applies it | What it affects |
|---|---|---|
| On set | DIT or camera assistant loads it into monitors and camera | Director and video village see the look |
| Dailies | DIT or dailies lab, plus per-scene CDL adjustments | Dailies screeners and proxy files |
| Editorial | Baked into proxies | What the editor and producers watch for months |
| Final grade | Colorist loads the log originals, may start from the LUT | The finished image |
At the final color grading session, the colorist works from the untouched camera originals. The LUT is a reference, and the colorist may replace it with a proper color-managed pipeline for the deliverable color spaces.
Mistakes that cost time
Using the wrong LUT for the camera's log curve is the most common problem. A LUT built for one manufacturer's log encoding will produce odd contrast and color on another, which shows up fast on a mixed A and B camera package. Label LUT files with camera, log format, and version (for example LONGDRIVE_ARRI_LogC4_v3.cube).
Recording the LUT into the camera originals causes worse damage. Once baked in, clipped highlights cannot be recovered in the grade. Record log and apply the LUT only to monitoring outputs and proxies.
Version changes are the last trap, especially when nobody tells the lab. If Day 12 dailies used v3 and Day 13 used v4, the editor cuts between shots that look like they came from two different movies, and people waste hours before anyone checks the metadata.
Where it connects
LUT versions belong in the camera department's notes and on the camera report, and the final LUT or color pipeline is documented in the post workflow document. The finished grade, not the LUT, is what goes into the deliverables and gets checked in the QC report.