Assessment of Color Discrimination of Different Light Sources

Light quality is a key parameter of building design, which is mainly defined by the perceived luminance and the color rendering. Nowadays, there is a wide variety of metrics that do not converge in the color rendition evaluation of current light sources. The obsolescence of the Color Rendering Index promoted the rise of new procedures to provide an accurate evaluation. However, the score provided by most of these metrics does not distinguish between color deviation and hue discrimination, giving a single value to assess the overall color perception allowed by a light source. In this context, a new study is proposed, based on the evaluation of seven different light sources, comparing the results of the most recent color rendering metrics and those observed using a Farnsworth-Munsell trial carried out with 115 participants. The results obtained show that there is a notable divergence between color rendition and hue discrimination, although there is a clear proportionality between both. Moreover, a clear relationship is observed between color discrimination and the correlative color temperature of light sources, providing a better hue distinction with cool light sources, even though the psychological preferences of the participants do not coincide with the optimal scenario for color discrimination.