Transformation of NCS data into CIELUV colour space

Abstract

The CIE ( L ∗, u ∗, v ∗ ) system, abbreviated CIELUV, and the Swedish Natural Colour System (NCS) have been compared. The data for the NCS was transformed to CIELUV; the transformation involved taking the CIE tristimulus values of the nominal NCS notations, i.e. the colorimetric aimpoints representing the NCS, converting these values to CIELUV and plotting them in the CIELUV space. All the data has been calculated using CIE standard illuminant C and the 1931 standard observer. Although the data shows that no simple linear relationship exists between the NCS and CIELUV systems, the systems may nevertheless be considered closely related. Of the existing colour order systems, i.e. NCS, Munsell etc., the NCS is closest to CIELUV. As NCS represents the perceptual and cognitive aspects of colour better than CIELUV, the NCS may be considered as highly appropriate for a descriptive specification of colours for VDUs.