A report on Movie projector

35 mm movie projector in operation
Simulation of a spinning zoopraxiscope
An early projector and seats from a movie theater
1910's 35mm hand-cranked tinplate toy movie projector manufactured by Leonhard Müller in Nuremberg, Germany.
35 mm Kinoton FP30ST movie projector, with parts labeled. (Click thumbnail for larger text.)
Mechanical sequence when image is shown twice and then advanced. 
Outer sprockets rotate continuously while the frame advance sprockets are controlled by the mechanism shown – a Geneva drive.
Imaging lens Diastar of an Askania 35 mm movie projector (focal length: 400 mm)
Christie AW3 platter, BIG SKY Industries console, and Century SA projector
nonrewind in Royal – Malmö, Sweden
A diagram of the VistaVision format
A photo of a 35 mm film print featuring all four audio formats (or "quad track")- from left to right: SDDS (blue area to the left of the sprocket holes), Dolby Digital (grey area between the sprocket holes labelled with the Dolby "Double-D" logo in the middle), analog optical sound (the two white lines to the right of the sprocket holes), and the Datasat time code (the dashed line to the far right.)
Simulated wide screen image with 1.96 to 1 ratio as it would be seen in a camera viewfinder or on a theater screen
Simulated anamorphed image with 1.33 to 1 ratio (4:3) as it would appear on a frame of film

Opto-mechanical device for displaying motion picture film by projecting it onto a screen.

- Movie projector
35 mm movie projector in operation

32 related topics with Alpha

Overall

This animated cartoon of a galloping horse is displayed at 12 drawings per second, and the fast motion is on the edge of being objectionably jerky.

Frame rate

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Frequency (rate) at which consecutive images (frames) are captured or displayed.

Frequency (rate) at which consecutive images (frames) are captured or displayed.

This animated cartoon of a galloping horse is displayed at 12 drawings per second, and the fast motion is on the edge of being objectionably jerky.
Low frame rate video
Video with 4 times increased frame rate

To minimize the perceived flicker, projectors employed dual- and triple-blade shutters, so each frame was displayed two or three times, increasing the flicker rate to 48 or 72 hertz and reducing eye strain.

Working principle of a Maltese cross or Geneva drive

Intermittent mechanism

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Device or movement which regularly advances an object, web, or plastic film and then holds it in place.

Device or movement which regularly advances an object, web, or plastic film and then holds it in place.

Working principle of a Maltese cross or Geneva drive
Animation of a rotating shutter. The film is transported one frame when the shutter is blocking illumination of the film.
Film advance mechanism in the Soviet Luch-2 8mm film projector, based on a Reuleaux triangle.

This motion is critical to the use of film in a movie camera or movie projector.

Magna Tech, Electronic Film Recorders and Reproducer, SEPMAG

Sound follower

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Device for the recording and playback of film sound that is recorded on magnetic film.

Device for the recording and playback of film sound that is recorded on magnetic film.

Magna Tech, Electronic Film Recorders and Reproducer, SEPMAG
A Sound follower to the left of a Shadow Telecine

The sound recording would then be synchronized with a movie projector or a telecine.

Cue mark

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Visual indicator used with motion picture film prints, usually placed in the upper right-hand corner of a filmframe.

Visual indicator used with motion picture film prints, usually placed in the upper right-hand corner of a filmframe.

Most projection booths in movie theaters in the past (and in some older theaters and studio screening rooms today) were equipped with two projectors side-by-side to project reels of film alternating between the two projectors.

A 35mm film gauge illuminated with the flashlight of a smartphone.

Film gauge

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Physical property of photographic or motion picture film stock which defines its width.

Physical property of photographic or motion picture film stock which defines its width.

A 35mm film gauge illuminated with the flashlight of a smartphone.

Larger film gauge is generally associated with higher image quality, higher image detail, greater materials expense, heavier camera equipment, larger and most costly projection equipment, as well as greater bulk and weight for distribution and storage (both interim and archival).

Straight Geissler tubes filled with various gases

Geissler tube

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Early gas discharge tube used to demonstrate the principles of electrical glow discharge, similar to modern neon lighting.

Early gas discharge tube used to demonstrate the principles of electrical glow discharge, similar to modern neon lighting.

Straight Geissler tubes filled with various gases

Xenon arc lamps (for movie and IMAX projectors)

A cartridge of Kodak 35 mm (135) film for cameras.

Film format

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Technical definition of a set of standard characteristics regarding image capture on photographic film, for either stills or filmmaking.

Technical definition of a set of standard characteristics regarding image capture on photographic film, for either stills or filmmaking.

A cartridge of Kodak 35 mm (135) film for cameras.

Other characteristics usually include the film gauge, pulldown method, lens anamorphosis (or lack thereof), and film gate or projector aperture dimensions, all of which need to be defined for photography as well as projection, as they may differ.

Animation showing a six-position external Geneva drive in operation.

Geneva drive

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Gear mechanism that translates a continuous rotation movement into intermittent rotary motion.

Gear mechanism that translates a continuous rotation movement into intermittent rotary motion.

Animation showing a six-position external Geneva drive in operation.
An illustration that shows the four stages (motion stop at 90 degrees angle) of one full cycle of Maltese cross.
Movie Projector with hand crank and Geneva drive
Geneva stop with five spokes
Motion curves for one turn of the drive wheel, from top to bottom: angular position θ, angular velocity ω, angular acceleration α and angular jerk ja.
Internal Geneva drive
Animation showing an internal Geneva drive in operation
Spherical Geneva drive

One application of the Geneva drive is in film movie projectors and movie cameras, where the film is pulled through an exposure gate with periodic starts and stops.

The projection booth in the Savoy Theatre, Monmouth.

Projection booth

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Room or enclosure for the machinery required for the display of movies on a reflective screen, located high on the back wall of the presentation space.

Room or enclosure for the machinery required for the display of movies on a reflective screen, located high on the back wall of the presentation space.

The projection booth in the Savoy Theatre, Monmouth.

These include isolating the noise produced by opto-mechanical projectors from the audience, providing appropriate atmospheric control for the projection and film transport equipment (including, in more advanced booths, the use of HEPA air filtration to prevent dust contamination of the film prints in use), the provision of work space for the projectionist to prepare prints for projection and maintain the equipment, and the isolation of dangerous equipment and infrastructure (e.g. potentially explosive xenon bulbs and three-phase power) from untrained members of the public.

A biconvex lens

Lens

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Transmissive optical device which focuses or disperses a light beam by means of refraction.

Transmissive optical device which focuses or disperses a light beam by means of refraction.

A biconvex lens
Lenses can be used to focus light
Light being refracted by a spherical glass container full of water. Roger Bacon, 13th century
Lens for LSST, a planned sky surveying telescope
Types of lenses
The position of the focus of a spherical lens depends on the radii of curvature of the two facets.
A camera lens forms a real image of a distant object.
Virtual image formation using a positive lens as a magnifying glass.
Images of black letters in a thin convex lens of focal length f are shown in red. Selected rays are shown for letters E, I and K in blue, green and orange, respectively. Note that E (at 2f) has an equal-size, real and inverted image; I (at f) has its image at infinity; and K (at f/2) has a double-size, virtual and upright image.
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An aspheric biconvex lens.
Close-up view of a flat Fresnel lens.

Other uses are in imaging systems such as monoculars, binoculars, telescopes, microscopes, cameras and projectors.