LUT Cube Creator Node

LUT Cube Creator generates a neutral test pattern (an unfolded "color cube") that encodes every possible RGB combination. When you grade it with color correction nodes, Fusion can extract the matching color transform as a 3D LUT.

The idea: if you know how each reference color was changed, you know how to change any color the same way (interpolation inside the RGB cube). That is how a 3D LUT works.

• Effects Library: Tools > LUT > LUT Cube Creator
• Quick add: right-click in the Node Editor → Add Tool > LUT > LUT Cube Creator

1. LUT Cube Creator generates the neutral image (this node).
2. You pass this image through color correction nodes (Color Corrector, Curves, Hue Curves, etc.) → every color of the cube is transformed.
3. Option A: LUT Cube Analyzer → exports the result as a .cube / .3dl / .alut3 file (portable, reusable).
4. Option B: LUT Cube Apply → applies the encoded color transform directly to other footage (no file involved).

It is a powerful workflow to create your own LUTs from a grade done in Fusion, without going out to third-party software.

• No input - this node is a pure generator. It produces its image with no external dependency.

Creating a custom .cube file:
LUT Cube Creator → Color Corrector (grade freely) → LUT Cube Analyzer
                                                          ↓
                                                    .cube file

Applying the look to a shot without a file:
LUT Cube Creator → Color Corrector (grade) → LUT Cube Apply FG input
                                                    ↑
                          MediaIn (shot to grade)────┘ (BG input)
                                                    ↓
                                                MediaOut

Pattern Type

Layout of the cube unfolded into a 2D image:

• Horizontal - a long horizontal strip.
• Vertical - a long vertical strip.
• Rect - a rectangular grid. The most compact format.

Size / Precision

Size of the cube in samples per dimension:

• 33 × 33 × 33 (~36k samples) - standard, fast.
• 65 × 65 × 65 (~274k samples) - high precision, heavier.

33 × 33 × 33

The industry standard. Enough for most grades. Compatible with every system that supports 3D LUTs. 35,937 sampled colors.

65 × 65 × 65

Double the precision. Better for grades with subtle gradients or aggressive transforms. 274,625 samples. A bigger file, but negligible on a modern drive.

Rule of thumb: 33³ by default. 65³ if your grades show banding, or for HDR / wide gamut work.

• Creating a custom .cube file - grade an image in Fusion with every available tool, then export it as a LUT for use in other software (Premiere, After Effects, the DaVinci Resolve Edit page).
• Baking a color correction chain - rather than having 10 grading nodes in a row (slow to render), bake them into a 3D LUT with this workflow → File LUT = a fast render.
• Recreating a look supplied by the colorist - reproduce the grade values on the Cube Creator → export = a LUT the whole team can reuse.
• Analyzing an existing LUT - apply a LUT to the Cube Creator → the Analyzer exports the LUT again (useful to convert between formats, or tweak it slightly).
• Personal look library - create several LUTs for different moods (warm, cool, desaturated, vintage) and apply them quickly through File LUT.

• Always use 32-bit floating point when you work with the Cube Creator - otherwise subtle gradients get quantized and the generated LUT will show visible banding.
• Do not modify the Cube Creator itself - leave it neutral (1:1 output if connected directly to the Analyzer/Apply). The corrections belong on separate nodes between the Creator and the Analyzer/Apply.
• A single grading chain - if you put Merges or spatial operations between the Creator and the Analyzer, it does not work (the LUT only encodes color mappings, not spatial distortions).
• 3D LUTs do not encode everything - sharpen, blur, distortion and effects that depend on neighboring pixels are not captured. Only color transforms that depend solely on the current pixel's color.
• Rect pattern by default - easier to view and check than Horizontal or Vertical (which are long strips).
• Precision vs size - 33³ gives a file of about 1 MB, 65³ about 8 MB. On disk that is negligible, but a 65³ takes longer to load. 33³ is enough for 95% of uses.