colour.colorimetry.lightness_CIE1976

colour.colorimetry.lightness_CIE1976(Y, Y_n=100)[source]

Returns the Lightness \(L^*\) of given luminance \(Y\) using given reference white luminance \(Y_n\) as per CIE 1976 recommendation.

Parameters:
  • Y (numeric or array_like) – luminance \(Y\).
  • Y_n (numeric or array_like, optional) – White reference luminance \(Y_n\).
Returns:

Lightness \(L^*\).

Return type:

numeric or array_like

Notes

Domain Scale - Reference Scale - 1
Y [0, 100] [0, 1]
Range Scale - Reference Scale - 1
L_star [0, 100] [0, 1]

References

[CIETC1-482004m], [Wyszecki2000bd]

Examples

>>> lightness_CIE1976(12.19722535)  # doctest: +ELLIPSIS
41.5278758...