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Exposure-duration effects in localization judgments.

C A Burbeck
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Abstract

The effects on localization accuracy of increasing exposure duration beyond 100 msec are explored for a wide range of object separations. Previous reports that localization accuracy for objects separated by a few minutes of arc increases for exposures up to at least 400 msec are confirmed. I report here that localization of larger objects at larger separations does not improve when the exposure duration is increased beyond 100 msec. This difference between the small- and large-scale results can be explained by the difference in the spatial-frequency content of the objects being localized: When high-frequency objects are substituted for spectrally broadband objects in the large-scale case, the exposure-duration effects for widely separated objects become similar to those obtained in the small-scale case. These results suggest that the exposure-duration effect previously reported in hyperacuity studies is not specific to the localization task per se but rather is a suprathreshold version of the familiar form of spatiotemporal interaction seen in contrast-threshold results. They also suggest that a single type of mechanism underlies small- and large-scale localization.

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Differential ThresholdHumansPsychological TestsSpace PerceptionTime FactorsVisual AcuityVisual PerceptionJournal ArticleResearch Support, U.S. Gov't, Non-P.H.S.

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C A Burbeck. 1986. Exposure-duration effects in localization judgments.. https://doi.org/10.1364/josaa.3.001983

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