Hue Angle (H°)
Definition
A colorimetric parameter derived from chromaticity coordinates (commonly a* and b* in CIELAB) that expresses the sample’s perceived hue as an angular position on the chromatic plane, conventionally calculated with an atan2(b*, a*) function and reported in degrees (H°); it indicates dominant hue direction but conveys no information about lightness or chroma magnitude on its own.