Motion-Picture Camera

a device for photographing objects on film at fixed time intervals in the form of a series of sequential pictures (frames) used to create the film.

The optical portion of a motion-picture camera includes the camera lens, which forms the image of the object on the light-sensitive layer of the film, and the viewing system (viewfinder), for observing the object being filmed and the required location of the camera relative to the object. In reflex cameras, the light rays are directed into the viewer by the mirror and the mirror shutter during the time that they block the light rays traveling toward the film gate. The image observed through the viewfinder is produced on the plane, matte surface of the collector lens. The camera may have one permanent lens, which is built into the housing, or a set of interchangeable lenses with various focal lengths. The interchangeable lenses on a camera are located either in individual carrying cases or on a rotating device called a turret. Adapters are used to change the focal length of a permanent lens (they are usually telescopic systems with variable angular magnification); they also may be located on the turret. Certain cameras are equipped with lenses having a variable focal

Table 1. Characteristics of some motion-picture cameras (as of 1971)
Model number and name¹	Film width (mm)	Speed of photography (frames/sec)	Magazine capacity (m)	Means of focusing and viewfinder system	Drive²	Weight (kg)	Use³
¹ Cameras are Soviet-made unless otherwise noted
² Types of drive: E—electric motor; M—manual; S—spring
³ Types of films: O—ordinary; WS—wide-screen; WF—wide-gauge
1-SShS Rossiia	70	24	300	By distance scale and focusing screen; eyepiece with mirror shutter	E	68	Synchronous photography of WG films
70-KSK	70	12–90	150 and 300	By distance scale and focusing screen; through-the-lens sighting and telescopic viewfinder attachment	E	45	Combined and speeded-up photography of WG films
1-KSShR	70	12–32	40 and 75	By distance scale and focusing screen; eyepiece with mirror shutter	E and M	7	Hand-held photography of WG films
3-KSS Mir	35	24	300	By distance scale and focusing screen; through-the-lens sighting and telescopic viewfinder attachment	E	66	Synchronous photography of O and WS films
3KSKhM Rodina	35	16–32	120 and 300	By distance scale and focusing screen; eyepiece with mirror shutter	E and M	18	Nonsynchronized photography of O and WS films
PSK-29	35	24	60 and 120	By distance scale and focusing screen; through-the-lens sighting	E	22	Combined photography of O and WS films
1-KSRSh Konvas-avtomat	35	8–32	60	By distance scale and focusing screen; interchangeable eyepieces with mirror shutter	E, S, M	5, 9, and 8	Hand-held photography of O and WS films
Arriflex (FRG)	35	8–30	60 and 120	By distance scale and focusing screen; eyepiece with mirror shutter	E	4.3	Hand-held photography of O films
16-SK Rus’	16	25	120 and 300	By distance scale and focusing screen; through-the-lens sighting and telescopic viewfinder with parallax correction	E and M	21	Synchronized filming
16-SPM	16	12–48	30 and 60	By distance scale and focusing screen; through-the-lens eyepiece	E	3.8	Photography of newsreel and documentary films
Krasnogorsk-2	16	8–48	30	By distance scale and focusing screen; eyepiece with mirror shutter	S	3	Photography of newsreels and home movies
Admira 16A Elektrik (Czechoslovakia)	16	8, 16, 24, and 32	15 and 30	By distance scale and focusing screen; through-the-lens eyepiece	E	23	Newsreel and documentary photography
Kvarts-5	2 × 8	8–48	10	By distance scale and focusing screen; eyepiece with mirror shutter	S	1.5	Photography of newsreels and home movies
Kvarts 2 × 8s=1	2 × 8S	12; 18; 24 and 48	10	Lens focused at a distance of 4 m; telescopic viewfinder	S	1.2	Photography of home movies in super 8
Canon Reflex Zoom 8–3 (Japan)	2 × 8	8; 12; 16; 24; 32; 48; 64	10	By distance scale and focusing screen; eyepiece with mirror shutter	S	1.3	Newsreel and amateur photography

length (zoom lenses). The viewing devices of motion-picture cameras are divided into parallax and nonparallax types. In parallax viewers, the viewing line is displaced relative to the optical axis of the camera lens by a certain distance, and as a result the field of vision of the viewer is displaced relative to the picture field of the camera lens. Through-the-lens systems and mirror viewfinders are among the nonparallax viewfinders.

The mechanical portion of a motion-picture camera includes the feeding device, the drive, and the shutter. The feeding device moves the film from the feed roller to the take-up roller. A sprocket wheel evenly draws the film from the feed roller and directs it to the film guide. The intermittent movement of the film past the film gate is provided by a feed mechanism which is usually of the claw type. Loops are formed ahead of the film guide and behind the feed mechanism, providing for unimpeded operation of the claw mechanism. To feed the required length of film onto the take-up roller, there is a hold-back sprocket, which provides even delivery of the film. The feed sprocket, the claw mechanism, the hold-back sprocket, and the driveshaft of the center of the take-up roller turn at a fixed speed, depending on the filming speed. The feed mechanism also includes various types of auxiliary devices, such as hold-down and guide rollers and film removers. The shutter, which is usually made in the form of a disk with a variable opening (the angle of the opening is α₀), is designed to periodically cut off the light rays incident on the film gate, during the advance of the film frame. In certain cameras, this angle can be varied manually or automatically for filming a fade-out or fade-in, as well as for adjusting the exposure time of the light-sensitive layer of the film.

Both Soviet and foreign motion-picture cameras are produced for use with film of various widths and a varying frame size (see Table 1). Depending on this, a distinction is made between wide-frame cameras, for making 70-mm wide-screen films; for making ordinary, wide-screen, and cropped 35-mm films; for making 16-mm television, news, scientific, educational, and amateur films; and for making 8-mm or 2 × 8-mm educational and amateur films.

In terms of purpose and design features, motion-picture cameras are classified as hand-held and stationary. The cameras are also divided into synchronized types, with a low noise level (for filming with separate, synchronized recording of sound, usually on a magnetic tape); precision types, with high precision in the film advance for combined filming in two or more exposures; specialized cameras for filming panoramic, circular, and stereoscopic films; home cameras using 16- and 8-mm (2 × 8-mm) film; and special cameras with high filming speeds, which are used for recording rapidly or briefly occurring processes, as well as in aviation and space flight.

Most Soviet and foreign amateur cameras are equipped with built-in light meters, which are used for automatic setting of the required lens aperture. Cameras are also equipped with various sorts of auxiliary attachments such as anamorphic attachments for shooting wide-screen films, light filters, lens shades, mattes, and film footage counters.

Professional and amateur motion-picture cameras are being perfected both through improvement of the existing models and through development of new designs. Improvement of motion-picture cameras is mainly achieved by changing assemblies and mechanisms that broaden their operational capabilities, such as increasing the capacity of the magazines, using lenses with variable focal length, automating the lens focusing and exposure setting processes, and by remote control of the camera. Recently produced amateur cameras (1970) are also designed to use 8-mm film with an enlarged frame (the Super 8 size). Motion-picture cameras for scientific photography are also undergoing intensive improvement and development. They include small airborne cameras, motion-picture cameras for microphotography, highspeed and raster cameras, and photorecording units.

REFERENCES

Weise, H. Kinos”emochnaia kamera. Moscow, 1958. (Translated from German.)
Gordiichuk, I. B. Sovetskaia kinos”emochnaia apparatura. Moscow, 1966.
Kulagin, S. V. Kinos”emochnaia i kinoproektsionnaia apparatura. Moscow, 1967.

S. V. KULAGIN

motion-picture camera

Motion-Picture Camera