Abstract
Although visual artists and photographers know that a viewer’s gaze can be guided by selective use of image clarity and blur, there has been little systematic research. For example, there are hints that clarity and blur may play different roles in guiding attention when they are implicit cues to attention (Veas et al., CHI 2010) versus when they are the explicit targets of a task (Kosara et al., VRVis 2001) but systematic comparisons have not been done. In this study, 24 participants performed two eye-tracking tasks with the same naturalistic photographs, a recognition memory task in which manipulated image regions were not mentioned to participants (Experiment 1), followed by a visual search task in which these regions were explicit targets (Experiment 2). The results from the implicit task in Experiment 1 showed that fixations occurred more rapidly and frequently to a local region of clarity in a photo than to a comparable blurred region. However, this bias was completely reversed in the visual search task of Experiment 2, where fixations and manual responses were faster to targets that were blurred than to those that were sharp. These findings emphasize that the spontaneous tendency of viewers’ eyes to seek out regions of clarity in a photo does not mean image blur is ignored. Rather, the exquisite sensitivity to blur is evidence that these signals are integral to the strong association in everyday vision between image clarity (achieved through accommodation, vergence, and foveation) and focused attention (achieved through directed gaze).
Meeting abstract presented at VSS 2012