Evidence
Skin-tone test
This site promises that its tonal layers move luminance and leave colour where they found it, on every skin tone. This page is the measurement behind that promise, rendered from the JSON the build’s own harness writes — the prose here cannot drift from the numbers because it does not contain them.
What is measured, and on what
Nine synthetic reference patches along a plausible skin locus, from the lightest to the deepest, each a textured oval with a blemish and a red pupil in it. Every layer is run at its maximum — past what the controls allow — and hue and chroma inside the mask are compared before and after. The limits are 1.5 degrees of hue and 3 per cent of chroma.
These are synthetic tones, not people. A corpus of real, rights-cleared portraits with model releases is the next step and is not published yet. Until it is, this page says exactly what it measures and nothing more.
Last run 2026-10-24: every tone and every case passed.
Every layer at maximum, per tone
| Tone | Mask coverage | Hue drift | Chroma drift | Moved | Result |
|---|---|---|---|---|---|
| 246, 219, 199 | 95.3% | 0.292° | 0.49% | 3.21% | within limits |
| 235, 199, 173 | 95.3% | 0.191° | 0.31% | 3.9% | within limits |
| 223, 184, 152 | 95.2% | 0.185° | 0.276% | 4.64% | within limits |
| 204, 158, 124 | 95.1% | 0.126° | 0.237% | 5.76% | within limits |
| 181, 130, 99 | 95.1% | 0.097° | 0.251% | 6.93% | within limits |
| 150, 104, 78 | 95.2% | 0.128° | 0.374% | 7.39% | within limits |
| 118, 80, 60 | 95.3% | 0.179° | 0.603% | 7.66% | within limits |
| 88, 58, 44 | 95.7% | 0.234° | 1.011% | 8.57% | within limits |
| 62, 41, 32 | 96.1% | 0.289° | 1.486% | 10.61% | within limits |
Each layer against its own rule
Luminance-only layers are held to the limits above on the Cb/Cr plane the engine holds fixed. The layers that move colour on purpose — teeth, the Colour brush, white balance — are held to their own declared bounds instead. Worst case across the nine tones:
| Layer | Rule | Hue | Chroma | Result |
|---|---|---|---|---|
| eyes 100 | luminance only: Cb/Cr hue within 1.5 deg and chroma within 3% | 0.597° | -2.14% | within its rule |
| exposure +1.25 | luminance only: Cb/Cr hue within 1.5 deg and chroma within 3% | 0° | 0% | within its rule |
| exposure -1.25 | luminance only: Cb/Cr hue within 1.5 deg and chroma within 3% | 0° | 0% | within its rule |
| exposure +0.33 | luminance only: Cb/Cr hue within 1.5 deg and chroma within 3% | 0° | 0% | within its rule |
| exposure -0.33 | luminance only: Cb/Cr hue within 1.5 deg and chroma within 3% | 0° | 0% | within its rule |
| eye detail 100 | luminance only: Cb/Cr hue within 1.5 deg and chroma within 3% | 0° | 0% | within its rule |
| soften line | luminance only: Cb/Cr hue within 1.5 deg and chroma within 3% | 0° | 0% | within its rule |
| shine | luminance only: Cb/Cr hue within 1.5 deg and chroma within 3% | 0° | 0% | within its rule |
| under-eye | luminance only: Cb/Cr hue within 1.5 deg and chroma within 3% | 0° | 0% | within its rule |
| light cast 8 | uniform cast at the Light cap, |dL*| <= 2 | 4.665° | 88.24% | within its rule |
| teeth 100 | chroma falls 0-60%, L* never falls | 1.034° | -39.24% | within its rule |
| colour +100 | chroma rises 0-100%, hue <= 4 deg, |dL*| <= 2 | 1.89° | 64.55% | within its rule |
| colour -100 | chroma falls 0-85%, hue <= 4 deg, |dL*| <= 2 | 1.725° | -59.59% | within its rule |
| cast +24/-24 | clamped at 24, |dL*| <= 2 | 174.114° | -94.08% | within its rule |
A failure is published as a failure: the fix is to the gate or the layer, never to the threshold. The raw results are available as JSON.
Read next
- Even skin toneThe tone band evened at 30 per cent with texture removal at zero, so every pore stays.
- Skin smoothingOpens with the skin layer at 25 per cent, which leaves three-quarters of the texture.
- How far is too farWhere the caps sit, why they are there, and what the distance readout is measuring.
- Why nothing here reshapes a faceThe one exclusion that is a decision rather than a boundary, and the reasoning behind it.
