Persistence of vision in the context of "Movies"

A film is a work of visual art that simulates experiences and otherwise communicates ideas, stories, perceptions, emotions, or atmosphere through the use of moving images that are generally, since the 1930s, synchronized with sound and some times using other sensory stimulations.

Films are produced by recording actual people and objects with cameras or by creating them using animation techniques and special effects. They comprise a series of individual frames, but when these images are shown rapidly in succession, the illusion of motion is given to the viewer. Flickering between frames is not seen due to an effect known as persistence of vision, whereby the eye retains a visual image for a fraction of a second after the source has been removed. Also of relevance is what causes the perception of motion; a psychological effect identified as beta movement.

The term beta movement is used for the optical illusion of apparent motion in which the very short projection of one figure and a subsequent very short projection of a more or less similar figure in a neighbouring location are experienced as one figure moving.

The illusion of motion caused by animation and film is sometimes believed to rely on beta movement, as an alternative to the older explanation known as persistence of vision. However, the human visual system can't distinguish between the short-range apparent motion of film and real motion (where the successive positions of figures in successive impressions largely overlap), while the long-range apparent motion of beta movement is recognised as different and processed in a different way.

A movie camera (also known as a film camera and cine-camera) is a type of photographic camera that rapidly takes a sequence of photographs, either onto film stock or an image sensor, in order to produce a moving image to display on a screen. In contrast to the still camera, which captures a single image at a time, the movie camera takes a series of images by way of an intermittent mechanism or by electronic means; each image is a frame of film or video. The frames are projected through a movie projector or a video projector at a specific frame rate (number of frames per second) to show the moving picture. When projected at a high enough frame rate (24 frames per second or more), the persistence of vision allows the eyes and brain of the viewer to merge the separate frames into a continuous moving picture.