colour.constants.CIE_K

colour.constants.CIE_K = 903.2962962962963

CIE \(\kappa\) constant.

CIE_K : numeric

Notes

• The original CIE value for \(\kappa\) is \(\kappa=903.3\), Lindbloom (2003) has shown that this value is causing a discontinuity at the junction point of the two functions grafted together to create the Lightness \(L^*\) function.

  That discontinuity can be avoided by using the rational representation as follows: \(k=24389\ /\ 27\).

References

• [Lin03a]