Negative pulldown
Encyclopedia
Negative pulldown is the manner in which an image is exposed on a film stock
Film stock
Film stock is photographic film on which filmmaking of motion pictures are shot and reproduced. The equivalent in television production is video tape.-1889–1899:...

, described in the number of film perforations spanned by an individual frame. It can also describe the orientation of the image on the negative, whether it is captured horizontally or vertically. Changing the number of exposed perforations allows a cinematographer
Cinematographer
A cinematographer is one photographing with a motion picture camera . The title is generally equivalent to director of photography , used to designate a chief over the camera and lighting crews working on a film, responsible for achieving artistic and technical decisions related to the image...

 to change both the aspect ratio
Aspect ratio
The aspect ratio of a shape is the ratio of its longer dimension to its shorter dimension. It may be applied to two characteristic dimensions of a three-dimensional shape, such as the ratio of the longest and shortest axis, or for symmetrical objects that are described by just two measurements,...

 of the image and the size of the area on the film stock that the image occupies (which affects image clarity).

The most common film pulldowns are 4-perf and 3-perf, the latter of which is usually used in conjunction with Super 35. 2-perf, used in Techniscope
Techniscope
Techniscope or 2-Perf is a 35mm motion picture camera film format introduced by Technicolor Italia in 1963. The Techniscope format uses a two film-perforation negative pulldown per frame, instead of the standard four-perforation frame usually exposed in 35mm film photography...

 in the 1960s, is enjoying a slight resurgence due to the birth of digital intermediate
Digital intermediate
Digital intermediate is a motion picture finishing process which classically involves digitizing a motion picture and manipulating the color and other image characteristics. It often replaces or augments the photochemical timing process and is usually the final creative adjustment to a movie...

 techniques eliminating the need for optical lab work. Vertical pulldown is overwhelmingly the dominant axis of motion, although horizontal pulldown is used in IMAX
IMAX
IMAX is a motion picture film format and a set of proprietary cinema projection standards created by the Canadian company IMAX Corporation. IMAX has the capacity to record and display images of far greater size and resolution than conventional film systems...

, VistaVision
VistaVision
VistaVision is a higher resolution, widescreen variant of the 35mm motion picture film format which was created by engineers at Paramount Pictures in 1954....

 (still in use for some visual effects work), and in consumer and professional still camera
Still camera
A still camera is a type of camera used to take photographs. Traditional cameras capture light onto photographic film. Digital cameras use electronics, usually a charge coupled device to store digital images in computer memory inside the camera...

s.

History

Most 35mm film systems, whether they are camera
Camera
A camera is a device that records and stores images. These images may be still photographs or moving images such as videos or movies. The term camera comes from the camera obscura , an early mechanism for projecting images...

s, telecine
Telecine
Telecine is transferring motion picture film into video and is performed in a color suite. The term is also used to refer to the equipment used in the post-production process....

 equipment, optical printer
Optical printer
An optical printer is a device consisting of one or more film projectors mechanically linked to a movie camera. It allows filmmakers to re-photograph one or more strips of film...

s or projector
Movie projector
A movie projector is an opto-mechanical device for displaying moving pictures by projecting them on a projection screen. Most of the optical and mechanical elements, except for the illumination and sound devices, are present in movie cameras.-Physiology:...

s, are configured to accommodate the 4-perf system, where each frame of 35mm is 4 perforations long. 4-perf was (and remains) the traditional system, and virtually all projectors are based on 4-perf, because 4 perforations is the amount needed per frame vertically in order to have enough negative space for a roughly squarish image, which became the silent film standard aspect ratio
Aspect ratio (image)
The aspect ratio of an image is the ratio of the width of the image to its height, expressed as two numbers separated by a colon. That is, for an x:y aspect ratio, no matter how big or small the image is, if the width is divided into x units of equal length and the height is measured using this...

 of 1.33:1.

Later, when the film industry was facing the perceived threat of obsolescence to television
Television
Television is a telecommunication medium for transmitting and receiving moving images that can be monochrome or colored, with accompanying sound...

, which also was universally a 1.33:1 aspect ratio at the time (and remained so until the introduction of DTV
Digital television
Digital television is the transmission of audio and video by digital signals, in contrast to the analog signals used by analog TV...

), studios started experimenting with various competing widescreen formats.

Current practice

Eventually, aspect ratios of 1.85:1 in North America
North America
North America is a continent wholly within the Northern Hemisphere and almost wholly within the Western Hemisphere. It is also considered a northern subcontinent of the Americas...

 and 1.66:1 in Europe
Europe
Europe is, by convention, one of the world's seven continents. Comprising the westernmost peninsula of Eurasia, Europe is generally 'divided' from Asia to its east by the watershed divides of the Ural and Caucasus Mountains, the Ural River, the Caspian and Black Seas, and the waterways connecting...

 became standard for 35mm productions shot with normal non-anamorphic lenses. However, the way the aspect ratio is created with these films is not in-camera, but rather by placing a cropping device, known as an aperture mask, over the film in the projector. What this means is that most films are shot in full screen format (often incorrectly referred to as 1.33:1 but actually 1.37:1 because of the sound tracks), but composed for 1.85:1 or 1.66:1 and cropped that way in projection. Therefore, a fair percentage of the film is wasted, because the cropped top and bottom are never meant to be shown.
3-perf and 2-perf are only used in the origination and post-production transfer process.

2-perf

2-perf camera systems use only 2 perforations per frame on 35mm film, which gives an aspect ratio close to the 2.39:1 aspect ratio used in anamorphic prints. It was first proposed conceptually around 1930, but was not put into practice until 1961, when Techniscope
Techniscope
Techniscope or 2-Perf is a 35mm motion picture camera film format introduced by Technicolor Italia in 1963. The Techniscope format uses a two film-perforation negative pulldown per frame, instead of the standard four-perforation frame usually exposed in 35mm film photography...

 was developed at Technicolor
Technicolor
Technicolor is a color motion picture process invented in 1916 and improved over several decades.It was the second major process, after Britain's Kinemacolor, and the most widely used color process in Hollywood from 1922 to 1952...

's Italian branch. It has recently been brought up again with the advent of higher quality, lower grain film stock
Film stock
Film stock is photographic film on which filmmaking of motion pictures are shot and reproduced. The equivalent in television production is video tape.-1889–1899:...

s as well as digital intermediate
Digital intermediate
Digital intermediate is a motion picture finishing process which classically involves digitizing a motion picture and manipulating the color and other image characteristics. It often replaces or augments the photochemical timing process and is usually the final creative adjustment to a movie...

 post-production methods which eliminate optical blowups and thus improve quality. While in the recent past, some companies have offered custom conversions of camera equipment to 2-perf, it appears that camera manufacturers are now poised to support the format. Arri
Arri
-History:Arri was founded in Munich, Germany as Arnold & Richter Cine Technik in 1917, named after founders August Arnold and Robert Richter. They produce professional motion picture equipment, digital and film cameras and cinematic lighting equipment...

 made 2-perf movement blocks for their Arricam
Arricam
Arricam is a 35 mm movie camera line manufactured by Arri. It is Arri's flagship sync-sound camera line, replacing the Arriflex 535 line. The design was developed by Fritz Gabriel Bauer and Walter Trauninger, and is heavily derivative of the cameras Bauer created for his Moviecam company, which was...

 and Arriflex 235 cameras available for rental in March 2007, while Aaton
Aaton
Aaton is a motion picture equipment manufacturer, based in Grenoble, France. Aaton was founded by Eclair engineer Jean-Pierre Beauviala, whose efforts have been primarily focused on making quiet, portable motion picture hardware suitable for impromptu field use, as for documentaries...

's Penelope
Aaton Penelope
Aaton Penelope is a 35mm motion picture camera introduced by Aaton in October 2008. It's the first camera in the world designed as a switchable Techniscope or 3-perf shooting solution , and it's also the first 35mm camera to offer a progressive scan video-tap....

 camera, released in October 2008, was the first camera specifically designed for 2-perf usage (as well as 3-perf).

3-perf

3-perf solves the film wastage problem by changing the camera gate and shutter mechanism so that each frame is 3 perforations long. The 3-perf image is 1.78:1, which makes it both ideal for widescreen television and very close to 1.85:1 without having a perforation worth of wasted unused image. Because of this, the same amount of film footage will give 33% more shooting time, saving money on film stock; the camera will run more quietly because less film is moved through the camera per frame; and the Super 35 variant allows for a larger negative area, which can help compensate for increased grain when using higher-speed film stocks.

In the late 1990s, noted cinematographer Vittorio Storaro
Vittorio Storaro
Vittorio Storaro, A.S.C., A.I.C. is an Italian cinematographer.In 2003, a survey conducted by the International Cinematographers Guild judged Storaro one of history's ten most influential cinematographers.-Biography:...

 proposed a film standard known as Univisium
Univisium
Univisium is a proposed universal film format created by cinematographer Vittorio Storaro, ASC, AIC and his son, Fabrizio, to unify all future theatrical and television movies into one respective aspect ratio of 2.00:1...

 (also called Univision), which advocates 3-perf Super 35 to create a 2:00:1 aspect ratio.

Disadvantages of 3-perf and 2-perf

The only disadvantage of 3-perf and 2-perf is that if it is to be projected theatrically, it needs to be transferred back to a 4-perf system, which typically means a film print with black cropping on the print itself in order to fit the image onto a 4-perf frame - the same wastage problem as before. Even so, the amount of film shot on a production is much greater than the length of the final film, so 3-perf or 2-perf are still viable cost-saving options for production. Generally, 3-perf is most frequently used for widescreen
Widescreen
Widescreen images are a variety of aspect ratios used in film, television and computer screens. In film, a widescreen film is any film image with a width-to-height aspect ratio greater than the standard 1.37:1 Academy aspect ratio provided by 35mm film....

 television productions shot on film, because the film will be developed and then permanently transferred to video
Videotape
A videotape is a recording of images and sounds on to magnetic tape as opposed to film stock or random access digital media. Videotapes are also used for storing scientific or medical data, such as the data produced by an electrocardiogram...

, rendering projection incompatibilities irrelevant. Recently, this process has become popular with big-budget motion picture production, due to the advent of the digital intermediate
Digital intermediate
Digital intermediate is a motion picture finishing process which classically involves digitizing a motion picture and manipulating the color and other image characteristics. It often replaces or augments the photochemical timing process and is usually the final creative adjustment to a movie...

 process. The negative is scanned to high resolution (usually HD, 2K or 4K (digital cinema
Digital cinema
Digital cinema refers to the use of digital technology to distribute and project motion pictures. A movie can be distributed via hard drives, optical disks or satellite and projected using a digital projector instead of a conventional film projector...

)) digital files, colour graded, and ultimately printed back to standard 4-perf for projection. At some point in the future, the final 4-perf print may become unnecessary if the cinema distribution and projection chain become fully digital.

3-perf and 2-perf pose minor problems for visual effects work. The area of the film in 4-perf work that is not projected nonetheless contains picture information which is useful for such visual effects tasks as 2D and 3D tracking. This mildly complicates certain visual effects efforts for productions using 3-perf and 2-perf.

External links

  • Movie Making Manual wikibook article on Telecine including a list of facilities that can telecine 2-perf
The source of this article is wikipedia, the free encyclopedia.  The text of this article is licensed under the GFDL.
 
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