Corresponding color datasets and a Color Vision Model based on the OSA-UCS system

The most important part of any Color Appearance Model is the Chromatic Adaptations Transform (CAT), whose empirical ground is constituted by sets of corresponding colors, i.e. color pairs with equal appearance specification and belonging to different visual situations (different illuminants and/or different illumination levels). Today the CATs are reconsidered, since Brill and Mahy have shown their mathematical inconsistency. In 2004-2005 the author proposed an Adaptation Transform based on the Uniform Color Scale system of the Optical Society of America (OSA-UCS), where the visual adaptation transforms the cone activation stimuli into adapted stimuli. Today, only the OSAUCS system allows the definition of adapted stimuli. Two applications of this CAT are already published by requiring color constancy and using the definition of adapted stimuli given by OSA-UCS system. The present work considers all the available corresponding color datasets used for defining the usual CATs and 1) produces color-conversion matrices between all the visual situations considered for these corresponding color measurements; 2) shows the ambiguity existing in the definition of adapted stimuli, if not empirically defined; 3) proposes the measurements of adapted stimuli referred to the OSA-UCS system.