This paper describes work carried out to predict the result of a psychophysical experiment in which observers made judgments about the types of differences they perceived between originals and reproductions rendered on different media. The results of these observer–reported visual data are compared with analogous metrics extracted from colorimetric data of the corresponding originals and reproductions. While there is good agreement in terms of the most general findings, looking at more detailed results shows significant differences between visual and colorimetrically–based information. The paper then introduces a colorimetrically based image difference metric that takes into account some aspects of the human visual system. Using information both about the statistics of color differences, of the original images and of changes to spatial characteristics, the metric is able to give a close prediction of observer responses. The final delta-ICM metric is proposed for further testing as a means of predicting observer responses of image difference in cross–media color image reproduction as well as other applications.