Viewing paintings and drawings is a dynamic experience where observers can move about the object discerning surface structure such as brushwork and gloss in addition to color and composition. Conventional studio photography reduces the experience to a single viewpoint where the photographer uses experiential learning and aesthetic judgments. This dissertation had several research goals: improving the quality of estimated surface normal maps using only four studio strobe lights, evaluating the viability of a virtual viewing experience using computer graphics rendering software, understanding how gloss and texture are perceived through psychophysical experiments, and using this understanding to inform image rendering using computer graphics or conventional photography. This research improved the four strobe imaging technique by replacing the previously used polarizers on the camera and strobes with a mathematical thresholding technique. This reduced the number of images required to estimate surface normal and diffuse color by half while creating surface normal and color maps that could be used in a rendering software to generate virtual fine art images. With the need to improve fine art rendering practices in mind, a series of psychophysical experiments were performed. Observers were asked to assess the amount of perceived gloss and texture in sets of images that used different lighting configurations of the same samples. It was determined that observers have difficulty separating gloss and texture while performing discrimination tasks. From the results of the observations, it is assumed that texture influences gloss perception largely at raking lighting angles and gloss influences texture perception primarily at near normal lighting angles. Further exploring the perceived amount of gloss and texture in fine art images with different lighting geometries, observers were asked to rate the aesthetic appeal of these images. On average, observers preferred images with small amounts of both perceived gloss and texture. This research resulted in a successful imaging and rendering protocol that used a limited amount of studio equipment without sacrificing the capture of surface texture information as well as additional knowledge regarding the desirable amount of perceived gloss and texture that can be used in making lighting and rendering choices that are pleasing to observers while still representing the physical features of a work of art.
Color Science (Ph.D.)
Roy S. Berns
Cox, Brittany D., "Scientific Imaging of Cultural Heritage for Computer Graphics Rendering" (2017). Thesis. Rochester Institute of Technology. Accessed from
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