<title>Effects of ambient illumination and image color balance on the perception of neutral in hybrid image display systems</title>

Abstract

This paper describes a visual experiment in which a group of observers made forced choice judgments of the location of neutral in test images presented on a color CRT display and photographic reflection prints. The . CRT and photographic images were presented both separately and side-by-side in a simulated office environment under two conditions of ambient illumination, tungsten and daylight fluorescent. The results indicate that an observer's state of chromatic adaptation during image viewing is mainly dependent on image areas with little or no dependence upon the surrounding environment. With reflection images viewed in normal conditions, observers were noted to automatically discount ambient illumination.When viewing self-luminous images however, observers formed relative judgements only under certain conditions. These results are discussed in terms of their use in choosing white points for color reproduction calculations.