Induced Stereoscopic Motion as an Aid in the Search for Tall Targets

Abstract

Induced stereoscopic motion, ISM, is apparent movement in tall static objects projecting from a reasonably flat background when viewed stereoscopically. ISM is produced by a smooth but extensive variation of the stereo-base (the separation of camera points) in a pair of moving picture films. The two films are projected by two separate but synchronized projectors onto rear view screens which are placed in the field of view of a stereoscope. In a controlled test it was found that subjects located targets faster and with fewer errors with ISM film than with comparable film in which the stereo-base was fixed at the maximum of the ISM film. This improvement of search is due almost entirely to searchs for targets which are difficult to find. Easy targets were always found and found quickly by both methods. ISM is as yet a laboratory production, but plans are being made for developing its field and applicability.

The effect of induced fusional demand on static and dynamic stereoacuity thresholds: the digital Synoptophore

“…This supports the assertion by Worth (1901); if fusion is achieved, stereopsis is typically apparent, [2] and findings that stereoacuity is either normal or absent in intermittent exotropia. [18] We demonstrate that the presentations with changing disparity result in lower thresholds than static presentations, in line with previous findings [12, 19, 20].…”

Dynamic cues to binocular depth

“…31 Whilst no lateral motion was programmed in the target stimulus, a degree of lateral motion can be perceived in stimuli moving through depth, as the lateral motion is more readily detected than the depth change. 38 The data presented here provide evidence that the human visual system can utilise dynamic disparity information more effectively than static disparity signals, corroborating work performed by Weldon et al 29 This is distinct from other studies mentioned here, where the ability to detect motion was assessed. Our finding that dynamic disparity processing is superior to static processing warrants further investigation and potential development of a clinical test, to allow the full assessment of binocular potential to assist management decisions.…”

“…27,28 Furthermore, the time taken to identify which target is closest to an observer is significantly shorter when the target moves through depth, even if the stationary presentation has a larger amount of disparity. 29 When asked to compare static and dynamic targets, observers matched smaller amounts of disparity when motion in depth was present, compared with a static disparity target. 30 The presence of motion in depth enhances the perception of depth.…”

A Systematic Comparison of Static and Dynamic Cues for Depth Perception

“…11 Moreover, when observers were asked to detect depth in an approaching target that began with zero disparity, this was achieved more quickly than a stationary target with a larger disparity, indicating an enhanced sensitivity for dynamic stereoscopic targets. 12 Zinn and Solomon 13 measured the time taken for participants to determine the closest of four binocular targets with various relative disparities as they moved through depth toward the participant. The amount of time taken to determine the closest target did not correlate significantly with static stereoacuity scores as measured with either the TNO test (Lameris Instrumenten, Utrecht, The Netherlands) or Titmus tests.…”