The influence of lighting on visual perception of material qualities

We studied whether lighting influences the visual perception of material scattering qualities. To this aim we made an interface or “material probe”, called MatMix 1.0, in which we used optical mixing of four canonical material modes. The appearance of a 3D object could be adjusted by interactively adjusting the weights of the four material components in the probe. This probe was used in a matching experiment in which we compared material perception under generic office lighting with that under three canonical lighting conditions. For the canonical materials, we selected matte, velvety, specular and glittery, representing diffuse, asperity, forward, and specular micro facet scattering modes. For the canonical lightings, we selected ambient, focus and brilliance lighting modes. In our matching experiment, observers were asked to change the appearance of the probe so that the material qualities of the probe matched that of the stimuli. From the matching results, we found that our brilliance lighting brought out the glossiness of our stimuli and our focus lighting brought out the velvetiness of our stimuli most similarly to office lighting. We conclude that the influence of lighting on material perception is material-dependent.