Persistence of vision

Image persistence indicates a defective temporal resolution of the human eye. It is produced by the decay of the light stimulus on the retina, the lasting effect for a short time after the end thereof. Since then, merge images that follow one another in sufficient faster frame rate in the brain to form a continuous motion, the principle of persistence of vision is only the physiological basis of the motion picture photography and thus the film and television.

As a psychological basis of perception of moving images of the so-called stroboscopic effect is responsible. Although the persistence of vision plays an important role here, but it has nothing to do with the perception of motion in the film. This has already been proven in the 1920s by Paul F. Linke in experiments. Nevertheless, it is still often more widespread, even in the current literature, the false assumption that image persistence is a prerequisite for the perception of the moving image in the human eye. However, the afterimage effect only causes a merger by the superposition of these individual images, which the film sensation - simply - " smoothes ". Only the combination of strobing and afterimage causes movement in the film, as we know it today. The flipbook example based solely on the stroboscopic effect.

These Zglinicki " phenomena that are based on image retention, have nothing to do with the cinematography basically. Only stroboscopic phenomena - but in conjunction with the persistence of vision - must be addressed as an immediate precursor of the film ".

An example to illustrate: to tie a light source to a string and letting it circulate quickly. Because of the lack of a stroboscopic interruption no movement is now perceived, but by the Phi - effect ( after-image ) merge the successive images, and it is only a light circle perceived as a whole.