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Stereoscopic depth constancy depends on the subject's task.

A Glennerster·B J Rogers·M F Bradshaw
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Abstract

Under identical viewing conditions, observers made two types of judgement about the shape of stereoscopically defined surfaces: one required an estimate of viewing distance for correct performance (e.g. setting the depth of a hemi-cylinder to equal its half-height or a dihedral angle to 90 deg), the other did not (matching the depth of, for example, sinusoidal corrugations or hemi-cylinders presented at two distances). Depth constancy for the two types of task was about 75% and 100%, respectively. We argue that observers may use a simple "direct" strategy to perform the depth matching task rather than constructing and comparing a metric representation of each surface.

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Convergence, OcularDepth PerceptionDistance PerceptionForm PerceptionHumansMathematicsPattern Recognition, VisualPsychometricsVision DisparityJournal ArticleResearch Support, Non-U.S. Gov't

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A Glennerster, B J Rogers, M F Bradshaw. 1996. Stereoscopic depth constancy depends on the subject's task.. https://doi.org/10.1016/0042-6989(96)00090-9

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