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Helmholtz–Kohlrausch phenomenon

change in brightness of perceived colour, produced by increasing the purity of a colour stimulus while keeping its luminance constant within the range of photopic vision

Note 1 to entry: For related colours, a change in lightness can also occur when the purity is increased while keeping the luminance factor of the colour stimulus constant.

Note 2 to entry: This entry was numbered 845-02-34 in IEC 60050-845:1987.

Note 3 to entry: This entry was numbered 17-531 in CIE S 017:2011.

Publication date: 2020-12
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