SUBTRACKT_
Colour grading that works by removing, not adding.
5 subtractive colour axes. 14 film-inspired presets. Oklab colour space. Metal GPU. The opposite of pushing sliders until something breaks.
One-time purchase. No subscription. No account.
The qualm
Additive grading pushes colour into images. Subtractive grading reveals what is already there.
Standard colour tools work by adding energy to channels: more saturation, more lift, more contrast. The image accumulates decisions. Film stock worked differently — the photochemical process defined a ceiling, and the grade happened by pulling away from it.
SUBTRACKT_ models that approach. Five axes let you suppress colour ranges rather than amplify them. The result is cohesion rather than addition. Grades that hold together across different sources.
5 Axes
Subtract. Shape. Control.
Warm / Cool
Suppresses warm or cool tones in Oklab. Pull heat out without shifting green or magenta.
Teal / Orange
Selective suppression along the teal-orange opponent axis. Neutralise the skin-sky split.
Magenta / Green
Suppression along the magenta-green axis. Surgical removal without touching adjacent hues.
Saturation
Perceptually uniform chroma reduction in Oklab. No hue shift as colour decreases.
Depth
Luma-weighted chroma suppression in the shadow range. Cleaner blacks without grading the whole image.
14 Presets
Film-stock references. Not looks.
Each preset was built by studying how real film stocks handled colour suppression across their response curves. The specific way a stock traded chroma for luminance fidelity at different exposure levels.
Film Print
Clean
Magic Hour
Tungsten Print
Moonlight
Overcast
Blockbuster
Neon Noir
Bleach Bypass
Faded Dailies
Muted Fashion
Technicolor Pull
Kodachrome
Copper Tone
Colour science
Oklab. Hue stays constant as chroma decreases.
HSL saturation reduction rotates hue at the edges of the gamut. Colours shift when you desaturate them. Oklab suppression moves straight inward along the chroma axis. The hue angle does not change. The colour becomes less intense, not different.
Subtraction that does not introduce new decisions.
Under the hood
Metal GPU. Real-time. Full bit depth.
Apple Metal
Native GPU compute. Zero-copy buffer pipeline. All five axes computed in a single GPU pass with no intermediate buffers.
Oklab throughout
Input converts to Oklab once. All five axes operate in perceptually uniform space. Single conversion back on output. No hue rotation artefacts.
Full bit depth
32-bit float throughout. Precision-critical in the shadow ranges where colour suppression is most visible.
Luma-weighted depth axis
The Depth axis uses bilinear luma weighting across the full tonal range. No hard rolloff. No clipped transitions.
Privacy
Offline. Always.
SUBTRACKT_ runs entirely on your GPU. No internet connection. No telemetry. No accounts. No cloud rendering. Your footage stays on your machine.
Safe for NDA work. Nothing leaves your system.
Requirements
What you need.
OS
macOS 13 Ventura
Or later. Apple Silicon and Intel.
Host
DaVinci Resolve 18+
Free or Studio. OpenFX host.
GPU
Metal support
All Macs from 2012 onward.
$30. Once. Done_
5 subtractive axes. 14 film presets. Oklab colour space. One-time purchase. No subscription. No account required.
Requires macOS 13 Ventura or later. DaVinci Resolve 18+ (Free or Studio).