Using eye tracking, we study the way viewers look at photos and image based NPR illustrations. Viewers examine the same number of locations in photos and in NPR images with uniformly high or low detail. In contrast, viewers are attracted to areas where detail is locally preserved in meaningfully abstracted images. This accords with the idea that artists carefully manipulate detail to control interest and understanding. It also validates the method of meanbstraction used in DeCarlo and Santella [2002]. Results also suggest eye tracking can be a useful tool for evaluation of NPR systems.