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Blur is commonly considered a weak distance cue, but photographic techniques that manipulate blur cause significant and compelling changes in the perceived distance and size of objects. One such technique is “tilt-shift miniaturization,” in which a camera’s lens is translated and slanted relative to the film plane. The result is an exaggerated vertical blur gradient that makes scenes with a vertical distance gradient (e.g., bird’s-eye view of landscape) appear significantly nearer and therefore smaller. We are currently investigating the conditions necessary to produce this effect, and have developed a Bayesian model for the visual system's use of blur as a distance cue. Interestingly, the model predicts that other cues to depth, such as perspective information, are necessary for blur to act as a cue to absolute distance. This has been verified using psychophysical studies (Held, et al., VSS 2009).