Cinematography and recording methods

"Classic" cinematography consists of a sequence of images recorded one after the other on a physical medium, traditionally photographic film or magnetic tape; four dimensions of space, time, and intensity are thus stored on the image medium.

More specifically, during a period known as exposure time, each image integrates photons distributed across two spatial dimensions, x and y, which constitute each elementary point of the image. The darkening of the film (measured in optical density) at this given point in the image provides the third dimension; it is related to the incident power (measured in watts) or energy (in joules) emitted by the corresponding point. The two quantities (exposure time t and interval dt between exposures) complete the temporal quantification of the shooting conditions. The sequence will therefore be characterized by the four-component "image...