Abstract
Even when geometrically accurate displays are used in virtual reality (VR), most labs report substantial compressions of perceived distance. That is, it is hard to effectively simulate large-scale spaces in VR; they look small. There have been reports that pre-exposure to the space that is being simulated (e.g., in a VR rendering of a lab space) produces accurate scaling. We sought to measure whether pre-exposure to our experimental hallway had an effect on locomotor distance judgments when that hallway was viewed in a head-mounted display (HMD) with a correctly scaled live video image. The task was to walk, without visual or auditory feedback, to a pre-viewed target. Subjects had never been to the experimental hallway before. Distances were in the range of 3 to 7 meters. There were three conditions of the experiment. In the normal vision condition, subjects simply wore the HMD as a hat (to match any postural influences) and viewed each target directly before closing their eyes and walking to it. In the live-video-only condition, subjects performed the same task while wearing an HMD without any pre-exposure to the hallway environment. In the pre-exposure condition, subjects were allowed to view the hallway directly from a single vantage point prior to donning the HMD and beginning the experiment using live video. Surprisingly, although the average proportional distance (walked/actual) with pre-exposure did not, in fact, differ from that with normal vision, proportional distances walked in the live-video-only condition were actually greater (M = 1.00) than those in the other two conditions (M = 0.87), t(18) = 2.13, p [[lt]] .05. While it is possible that subjects were actively compensating for a mismatch between perceived size and expected size of a generically familiar scene, the HMD itself is probably not primarily responsible for distance compression.