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Hue, value and chroma: the color science behind every palette
The three measurements that define every seasonal palette, and how color scientists put numbers on them.
Every seasonal palette is described by three qualities: undertone, value and chroma. These aren't fashion jargon. They come straight from how color scientists measure color.
Munsell's three dimensions
In 1905 the American painter and teacher Albert H. Munsell published A Color Notation, a system that describes any color with three numbers:
- Hue: where the color sits around the color wheel, such as red, yellow or blue.
- Value: how light or dark it is.
- Chroma: how intense it is compared with a gray of the same value.
Seasonal analysis borrows these directly. Undertone is a question of hue (does it lean golden or pink-blue?), and the Light, Deep, Bright and Soft palettes are named for value and chroma. The Sci\ART 12-season method was developed by Kathryn Kalisz, whose work drew on Munsell's system.
Putting numbers on perception
In 1976 the International Commission on Illumination (CIE) defined CIELAB, a color space designed so that equal distances roughly match equal perceived differences. It uses three axes:
- L* for lightness (value)
- a* for green to red
- b* for blue to yellow
From a* and b* you can calculate chroma (distance from gray) and hue angle (direction around the wheel). The same three dimensions appear again.
Measuring "close enough"
Color scientists express the difference between two colors as ΔE ("delta E"). The CIEDE2000 formula, published in 2001, corrects for known quirks in how people perceive blues, grays and saturated colors. As a rough guide, differences of about 1 to 2 are near the edge of what most people notice side by side, while differences above 10 look like clearly different colors.
How we use it
Our clothing analyzer converts a garment's dominant colors to CIELAB and measures the CIEDE2000 distance to all 192 swatches across the 12 palettes. The closest swatches decide the ranking. The full method is on our how it works page.
Sources
- Munsell, A. H. (1905). A Color Notation. Boston: G. H. Ellis.
- CIE (1976). CIE 1976 L*a*b* color space, International Commission on Illumination.
- Luo, M. R., Cui, G. & Rigg, B. (2001). The development of the CIE 2000 colour-difference formula: CIEDE2000. Color Research & Application.
- The Sci\ART system, Chromology