CIE 253:2024

This Technical Report includes an overview of seven methods to characterize specific colour rendition characteristics of white-light sources beyond colour fidelity. Methods to characterize colour fidelity are described in CIE 13.3-1995 “Method of measuring and specifying Colour Rendering Properties of light sources” and CIE 224:2017 “CIE 2017 Colour Fidelity Index for accurate scientific use”.

The seven described methods are:
• Colour Quality Scale (CQS),
• Colour Rendering Index (CRI)-based Colour Rendition Properties (CRI -CRP),
• Colour Rendering Vectors and Colour Saturation Icon (CRV and CSI),
• Feeling of Contrast Index (FCI),
• IES TM-30 Method,
• Memory Colour Rendition Index (MCRI),
• Preference Index of Japanese Skin Colour (PS).

This Technical Report neither ranks the methods nor recommends a specific method for the purpose of rating the adequacy of a white-light source for particular applications. The adequacy of a white-light source is likely to depend on the goal to be reached within a specific application field. The described methods are not intended to replace the general colour rendering index, R_a, or the general colour fidelity index, R_f, but they can be used to obtain a more complete description of the colour rendition characteristics of white-light sources, beyond colour fidelity.