Chromaticity shifts due to light exposure of inorganic pigments used in traditional Chinese painting

Abstract

Museum lighting must use a light source suitable for preserving the colours of the objects being lit. This paper examines how prolonged exposure to three light sources typically used in museums affect the chromaticity of five pigments commonly used in Chinese traditional heavy colour painting. The three light sources were tungsten halogen with an infrared filter, metal halide and an RYGB-type LED. The chromaticities of the pigments were measured at regular intervals over 1152 hours of exposure. These data were used to reveal the chromaticity shifts occurring and hence the relative effect of each typical light source. Of the three light sources measured, the RYGB-type LED had the least chromaticity shift, on average. These results provide a database for related research on Chinese traditional heavy colour painting illumination and provide a more general reference for the choice of light source in the design of museum lighting.