Open AccessImpact of cross-regional differences on color rendition evaluation of white light sources
Author(s) -
Kevin Smet,
Peter Hanselaer
Publication year - 2015
Publication title -
optics express
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.23.030216
Subject(s) - metric (unit) , naturalness , white light , index (typography) , color difference , optics , computer science , statistics , physics , mathematics , artificial intelligence , enhanced data rates for gsm evolution , operations management , quantum mechanics , world wide web , economics
In a study, involving laboratories from seven geographic regions, the memory colors of eleven familiar objects were investigated. Based on that study, one global and seven regional memory color rendition indices (MCRIs) are created and the impact of cross-regional differences on the evaluation of color rendition was investigated. A first analysis focuses on the impact on MCRI index values by comparing the regional index values, calculated for 401 light sources, with those of the global index. A second analysis examines the impact on predictive performance in terms of the visual appreciation and naturalness of rendered objects colors as evaluated in respectively twenty-one and fifteen experiments published in literature. Both analyses show that, although there are small differences in absolute level of color rendition, the regional metrics are generally comparable in terms of predicting light source rank order and correlation with visual data. Therefore, ànd considering between-region variability to be smaller than or of the same size as the within-region variability, a globally valid memory color rendition metric can be proposed without introducing substantial errors. Finally, Smet's Rm index, obtained using real objects, is suggested as a good approximation to that globally valid metric.