Technical details

Most of the optical and mechanical elements of a movie camera are present in the movie projector. The camera will not have an illumination source and will maintain its film stock in a light-tight enclosure. A camera will also have exposure control via an iris aperture located on the lens. Also, there is a rotating, sometimes mirrored shutter behind the lens, which alternately passes the light from the lens to the film, or reflects it into the viewfinder. Otherwise, the requirements for film tensioning, take-up, intermittent motion, loops, and rack positioning are almost identical. See the movie projector article for these details and for the various film formats used. The righthand side of the camera is often referred to by camera assistants as "the dumb side" because it usually lacks indicators or readouts and access to the film threading, as well as lens markings on many lens models. More recent equipment often has done much to minimize these shortcomings, although access to the film movement block by both sides is precluded by basic motor and electronic design necessities.

A spring-wound Bolex 16 mm camera
The standardized frame rate for commercial sound film is 24 frames per second. The standard commercial (i.e., movie-theater film) width is 35 millimeters, while many other film formats exist. The standard aspect ratios are 1.66, 1.85, and 2.39 (anamorphic). NTSC video (common in North America and Japan) plays at 29.97 frames/s; PAL (common in most other countries) plays at 25 frames/s. These two television and video systems also have different resolutions and color encodings. Many of the technical difficulties involving film and video concern translation between the different formats. Video aspect ratios are 4:3 for full screen and 16:9 for widescreen

Movie camera

The movie camera is a type of photographic camera which takes a rapid sequence of photographs on strips of film. In contrast to a still camera, which captures a single snapshot at a time, the movie camera takes a series of images, each called a "frame". This is accomplished through an intermittent mechanism. The frames are later played back in a movie projector at a specific speed, called the "frame rate" (number of frames per second). While viewing, a person's eyes and brain merge the separate pictures together to create the illusion of motion.