Coloured shadows described in a cone contrast space.

Abstract

Two effects which can modify the appearance of a colour seen in a context compared to isolation are chromatic induction and colour constancy. These effects transform colour in ways which depend on the visual system rather than physical characteristics of light and surfaces. They need not reflect different processes within the visual system, indeed, chromatic induction has been attributed to the same processes as those involved in constancy, or, as an error of the visual system attempting to achieve constancy. This hierarchy is not necessary: both constancy and induction may result from the same processes without requiring that one promotes the other or that constancy is a goal of the visual system. This study examines induction in terms of cone contrasts in a coloured shadow display, part of a study to establish a relevant measure of contrast and its role in chromatic induction and colour constancy.