Speed perception of dynamic lighting around daylight

Abstract

Dynamic lighting is an integral part of our experience of illumination, both in daylight and increasingly in artificial lighting. Previous research has focused either on daylight or chromatic illumination exclusively, and most studies examined speeds near detection thresholds. This experiment investigated suprathreshold transitions between neutral and chromatic illumination to expand upon these findings. The perceived speed of lighting changes to and from the chromaticity of D65 in eight radial hue directions was measured in a two-interval forced choice (21FC) task. The relative perceived speed, computed as the point of subjective equality (PSE), of transitions moving away from D65 differed by radial hue direction, indicating that CIELAB is temporally nonuniform. Results show that the yellow-blue opponent colour component contributes less to speed perception, in line with previous literature. The experiment did not yield PSEs for many transitions moving towards D65, likely because the comparison was too difficult, an improper range of speeds was studied, or both.