This paper describes a computational model based on CIELAB colorimetry and full tonal scale evaluation to define objective boundary conditions for “Retained Image Appearance” in a photograph where 100% retention equates to no visual change and 0% retention means total functional loss of image information content. The “Retained Image Appearance” model, I*, examines the color information (hue and chroma) and the black-and-white spatial information (lightness and contrast) in order to characterize the complete life cycle of a photograph as it ages with respect to color, contrast, and lightness. The I* model can also be used to compare tone reproduction accuracy between different renditions of a photographic image and may therefore have applicability in initial print or proof print quality studies as well.
Mark McCormick-Goodhart, Henry Wilhelm, Dmitriy Shklyarov, "A “Retained Image Appearance” Metric For Full Tonal Scale, Colorimetric Evaluation Of Photographic Image Stability" in Proc. IS&T Int'l Conf. on Digital Printing Technologies (NIP20), 2004, pp 680 - 688, https://doi.org/10.2352/ISSN.2169-4451.2004.20.1.art00036_2