What a colour analysis measures
Every system of seasonal colour analysis, whatever it calls the seasons, rests on the same four questions about your colouring. An analyst answers them by holding drapes against your face in daylight. We answer them by sampling your skin, hair and eyes from a portrait, converting the samples to CIELAB (the colour space built to match how people see difference) and reading four numbers off the result.
| Reading | What is measured | Where the cuts fall |
|---|---|---|
| Undertone | Hue angle of the skin sample, in CIELAB degrees. | Cool under 49° Neutral-cool 49° to 56° Neutral-warm 56° to 63° Warm 63° and above |
| Depth | Lightness of the skin sample, L* on a 0 to 100 scale. | Deep under 46 L* Medium-deep 46 L* to 58 L* Light-medium 58 L* to 68 L* Light 68 L* and above |
| Chroma | How saturated the skin reads, CIELAB chroma. | Soft under 36 Bright 36 and above |
| Contrast | Lightness gap between skin and hair, or the eyes when hair cannot be read. | Low under 25 L* Medium 25 L* to 40 L* High 40 L* and above |
Undertone is the hue angle of your skin: the lower the angle, the pinker and cooler; the higher, the more golden and warmer. It is the reading people try to guess from their veins, and the one lighting shifts most. Depth is lightness, L* on a scale where 0 is black and 100 is white. Chroma is saturation: how much colour your skin, eyes and hair carry together, against how muted they are. Contrast is the lightness gap between your skin and your hair, or your eyes when the hair cannot be read, and it decides how far apart the lights and darks in an outfit can sit before they overpower you.
Why the vein test keeps getting it wrong
Veins look bluer under light skin and greener under deeper skin whatever the undertone, so the test mostly measures depth and calls it undertone. The jewellery test measures what you own. Both are proxies for a number nobody was measuring.
A photo has its own trap: warm indoor light pushes every face warm, and a phone camera then guesses at a correction. So the read looks for the whites of your eyes and uses them as a white reference, correcting the whole image until they read neutral before it samples your skin. When the whites are not visible enough, the read still runs, says so, and carries a lower confidence.
The confidence is how far your skin sits from the nearest cut on undertone and depth, plus a little for a real white reference and a usable hair sample. A reading a degree from a boundary is reported as the near miss it is.
From four readings to one of 16 directions
The four readings place you in a family first, then in one of four directions inside it. The rules are short enough to print.
| Family | When | Directions inside it |
|---|---|---|
| Spring | Warm or neutral-warm undertone, and light or light-medium depth. Also medium-deep when the chroma is bright. | Light Spring when the depth is light; Bright Spring when the chroma is bright; Warm Spring when the undertone is fully warm; otherwise True Spring. |
| Autumn | Warm or neutral-warm undertone at the deeper depths. | Deep Autumn when the depth is deep; Soft Autumn when the chroma is soft; Warm Autumn when the undertone is fully warm; otherwise True Autumn. |
| Summer | Cool or neutral-cool undertone, and light or light-medium depth. Also medium-deep when the chroma is soft. | Light Summer when the depth is light; Soft Summer when the chroma is soft; Cool Summer when the undertone is fully cool; otherwise True Summer. |
| Winter | Cool or neutral-cool undertone at the deeper depths. | Deep Winter when the depth is deep; Bright Winter when the chroma is bright; Cool Winter when the undertone is fully cool; otherwise True Winter. |
Each family has twelve curated shades: eight that carry its character and four neutrals to build on. The reading decides the family, the family decides the palette. Nothing is generated per person; what changes per person is which of the four palettes is yours, and how confidently.