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Several years ago we wrote an article entitled "The Myth of Persistence of Vision" which appeared in the Journal of the University Film Association in the fall of 1978 (Anderson and Fisher).  In it we offered a considerable volume of evidence that the concept "persistence of vision" was an inaccurate and inadequate explanation of the apparent motion found in a motion picture.  At the time we thought the article had laid the matter to rest.  We had pronounced persistence of vision dead.  And frankly, we expected never again to hear the term, other than in an historical context.  

Several years ago we wrote an article entitled "The Myth of Persistence of Vision" which appeared in the Journal of the University Film Association in the fall of 1978 (Anderson and Fisher).  In it we offered a considerable volume of evidence that the concept "persistence of vision" was an inaccurate and inadequate explanation of the apparent motion found in a motion picture.  At the time we thought the article had laid the matter to rest.  We had pronounced persistence of vision dead.  And frankly, we expected never again to hear the term, other than in an historical context.  

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     Now, more than a decade later, we are drawn once more to the myth of persistence of vision.  Why?  Because it is still with us. [1]   We read a student paper, and we cringe.  We attend the lecture of a seasoned film scholar, and we cringe.  We cringe not only because they have chosen to perpetuate the notion of persistence of vision, but because they apparently, even at this late date, do not understand its implications.  By this time most film scholars seem to have heard of the inadaquacy of the term "persistence of vision."  Some have mistakenly substituted the generally misunderstood term "phi phenomenon" as an explanation of filmic motion, and many still cling to the myth. [2]  

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Now, more than a decade later, we are drawn once more to the myth of persistence of vision.  Why?  Because it is still with us. [1]   We read a student paper, and we cringe.  We attend the lecture of a seasoned film scholar, and we cringe.  We cringe not only because they have chosen to perpetuate the notion of persistence of vision, but because they apparently, even at this late date, do not understand its implications.  By this time most film scholars seem to have heard of the inadaquacy of the term "persistence of vision."  Some have mistakenly substituted the generally misunderstood term "phi phenomenon" as an explanation of filmic motion, and many still cling to the myth. [2]  

Why are film people so reluctant to let go of this notion?  Can it be that no one read our article back in 1978?  Surely not.  Tim Lyons, editor of the Journal at the time, has told us the article drew more response than any article published during his tenure.  No, the problem must be that we were correct when we proposed that "persistence of vision" functions as a unifying myth underpinning film scholarship.  The damned thing is a myth!  It won't die.  It still functions as a myth today.  Those engaged in film study cling to persistence of vision because they need it.  For film scholars, it is our myth of creation.  It answers our central question of origin:  Why, when we look at a succession of still images on the film screen or TV set, are we able to see a continuous moving image?  We answer,  "Persistence of vision."  Persistence of vision is the name given to the miracle by which the still silver halide dust of photography is tranformed into palpable, living motion.

Why are film people so reluctant to let go of this notion?  Can it be that no one read our article back in 1978?  Surely not.  Tim Lyons, editor of the Journal at the time, has told us the article drew more response than any article published during his tenure.  No, the problem must be that we were correct when we proposed that "persistence of vision" functions as a unifying myth underpinning film scholarship.  The damned thing is a myth!  It won't die.  It still functions as a myth today.  Those engaged in film study cling to persistence of vision because they need it.  For film scholars, it is our myth of creation.  It answers our central question of origin:  Why, when we look at a succession of still images on the film screen or TV set, are we able to see a continuous moving image?  We answer,  "Persistence of vision."  Persistence of vision is the name given to the miracle by which the still silver halide dust of photography is tranformed into palpable, living motion.

And just as the story of Adam and Eve explains not only the mechanism by which people originated and reproduced but also specifies the relationship of human beings to God, the myth of creation for the motion picture contains not only the mechanism for the origin of motion, but implies the relationship of the film to the viewer.  The viewer implied by the Myth of Persistence of Vision is a passive viewer upon whose sluggish retina images pile up.

And just as the story of Adam and Eve explains not only the mechanism by which people originated and reproduced but also specifies the relationship of human beings to God, the myth of creation for the motion picture contains not only the mechanism for the origin of motion, but implies the relationship of the film to the viewer.  The viewer implied by the Myth of Persistence of Vision is a passive viewer upon whose sluggish retina images pile up.

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Recent Findings

Recent Findings

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            At the same time, with almost total indifference to the problems of film scholars, researchers in several disciplines were pursuing problems in their own fields which would inadvertently shed light upon problems such as the phenomenon of motion in the motion picture.  One such avenue opened when psychologists began to explore the relationship of apparent motion to real motion.  They addressed themselves to the question of whether apparent motion and real motion are mediated by different mechanisms.  This inquiry, pursued in an effort to better understand motion perception per se, is directly relevant to the perception of the motion picture.  There is, after all, no motion on the screen.  There is only a succession of still images.  The motion in motion pictures is the result of a transformation made by our visual system.  An understanding of this transformation would be a first step in gaining an understanding of the complex set of transformations performed by the perceptual system when confronted with cinematic images.

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At the same time, with almost total indifference to the problems of film scholars, researchers in several disciplines were pursuing problems in their own fields which would inadvertently shed light upon problems such as the phenomenon of motion in the motion picture.  One such avenue opened when psychologists began to explore the relationship of apparent motion to real motion.  They addressed themselves to the question of whether apparent motion and real motion are mediated by different mechanisms.  This inquiry, pursued in an effort to better understand motion perception per se, is directly relevant to the perception of the motion picture.  There is, after all, no motion on the screen.  There is only a succession of still images.  The motion in motion pictures is the result of a transformation made by our visual system.  An understanding of this transformation would be a first step in gaining an understanding of the complex set of transformations performed by the perceptual system when confronted with cinematic images.

In research spanning more than two decades, Paul Kolers focused upon several ways in which the perception of apparent motion and of real motion differ.  In 1971 he and J.R. Pomerantz tested the effect of spatial intermittency on the illusion of motion.  They found that when two elements appeared on the screen, good illusory motion was seen with proper timing.  (This is the usual binary or two-element display, the limiting case for apparent motion.)  When four, eight, or sixteen elements appeared, smooth continuous motion was never attained.  However, with thirty-two or sixty-four or more elements, smooth continuous motion was again perceived.  Thus, if smooth continuity of motion was rated as a function of number of elements presented, the result would be a U-shaped curve.  Kolers concluded:  "It seems there is no necessary continuity of processing between spatially separated and spatially contiguous flashes; the ways the visual system constructs the two perceptions of motion seems to be quite different." (Kolers 39)   This suggests that multi-element or closely spaced displays may be mediated by the same mechanisms as real motion, while more widely spaced displays (the usual two-flash displays used to demonstrate apparent motion) involve a different type of processing.

In research spanning more than two decades, Paul Kolers focused upon several ways in which the perception of apparent motion and of real motion differ.  In 1971 he and J.R. Pomerantz tested the effect of spatial intermittency on the illusion of motion.  They found that when two elements appeared on the screen, good illusory motion was seen with proper timing.  (This is the usual binary or two-element display, the limiting case for apparent motion.)  When four, eight, or sixteen elements appeared, smooth continuous motion was never attained.  However, with thirty-two or sixty-four or more elements, smooth continuous motion was again perceived.  Thus, if smooth continuity of motion was rated as a function of number of elements presented, the result would be a U-shaped curve.  Kolers concluded:  "It seems there is no necessary continuity of processing between spatially separated and spatially contiguous flashes; the ways the visual system constructs the two perceptions of motion seems to be quite different." (Kolers 39)   This suggests that multi-element or closely spaced displays may be mediated by the same mechanisms as real motion, while more widely spaced displays (the usual two-flash displays used to demonstrate apparent motion) involve a different type of processing.

These two types of apparent motion -- that is, the perception of motion from multi-element or closely spaced displays, and the perception of motion resulting from more widely spaced displays -- have come to be termed short-range and long-range apparent motion, respectively.  The establishment of the defining characteristics of the two processes has been the focus of much of the research done in apparent motion in recent years.

These two types of apparent motion -- that is, the perception of motion from multi-element or closely spaced displays, and the perception of motion resulting from more widely spaced displays -- have come to be termed short-range and long-range apparent motion, respectively.  The establishment of the defining characteristics of the two processes has been the focus of much of the research done in apparent motion in recent years.

Persistence of vision - Revision history

SaikatMallick at 02:26, 8 July 2006

SaikatMallick at 02:25, 8 July 2006