Editing 35 mm movie film

<!--For clarity, the terms "movie" and "motion picture" are used in this article instead of "film".-->
{{short description|Standard theatrical motion picture film gauge}}
{{Use American English|date=March 2021}}
{{Use mdy dates|date=March 2021}}
{{about|the motion picture film gauge|the still photographic film gauge|135 film}}
{{Infobox product
| title            = 35 mm movie film
| image            = 35mm movie negative.jpg
| image_size       = 
| alt              = A reel of 35 mm black & white movie film negative stock
| caption          = 
| type             = [[Film stock]]
| inventor         = [[William Kennedy Dickson]]
| inception        = {{start date|1889}}
| manufacturer     = Edison company; [[Eastman Kodak]]
| available        = 
| current supplier = Kodak
| last production  = 
| models           = 
| website          = 
| notes            = 
}}
'''35 mm film''' is a [[film gauge]] used in [[filmmaking]], and the film standard.<ref name="Belton" /> In [[motion pictures]] that record on film, 35&nbsp;mm is the most commonly used gauge. The name of the gauge is not a direct measurement, and refers to the nominal width of the [[35 mm format]] [[photographic film]], which consists of strips {{convert|1.377|+/-|0.001|in|mm}} wide. The standard [[negative pulldown|image exposure length]] on 35&nbsp;mm for movies ("single-frame" format) is four [[film perforations|perforations]] per [[Film frame|frame]] along both edges, which results in 16 frames per foot of film.

A variety of largely proprietary gauges were devised for the numerous camera and projection systems being developed independently in the late 19th and early 20th centuries, along with various film feeding systems. This resulted in cameras, projectors, and other equipment having to be calibrated to each gauge. The 35&nbsp;mm width, originally specified as {{frac|1|3|8}} inches, was introduced around 1890 by [[William Kennedy Dickson]] and [[Thomas Edison]], using [[120 film]] stock supplied by [[George Eastman]]. Film 35&nbsp;mm wide with four perforations per frame became accepted as the international standard gauge in 1909, and remained by far the dominant film gauge for image origination and projection until the advent of digital photography and cinematography.

The gauge has been versatile in application. It has been modified to include sound, redesigned to create a safer [[film base]], formulated to capture color, has accommodated a bevy of widescreen formats, and has incorporated digital sound data into nearly all of its non-frame areas. [[Eastman Kodak]], [[Fujifilm]] and [[Agfa-Gevaert]] are some companies that offered 35&nbsp;mm films. As of 2015, Kodak is the last remaining manufacturer of motion picture film.<ref>{{cite web|url=https://www.hollywoodreporter.com/behind-screen/kodak-inks-deals-studios-extend-770300|title=Kodak Inks Deals With Studios to Extend Film's Life|website=The Hollywood Reporter|date=February 4, 2015|first1=Carolyn|last1=Giardina}}</ref>

The ubiquity of 35&nbsp;mm [[movie projector]]s in commercial [[movie theater]]s made 35&nbsp;mm the only motion picture format that could be played in almost any cinema in the world, until [[Digital cinema|digital projection]] largely superseded it.

==History and development==
===Early history===
{{See also|Film stock|Kinetoscope}}
[[File:Eastman giving Edison the first roll of movie film 01.png|thumb|Eastman (L) giving Edison the first roll of movie film, which was 35&nbsp;mm]]
In 1880, [[George Eastman]] began to manufacture [[gelatin]] dry photographic plates in [[Rochester, New York]]. Along with W. H. Walker, Eastman invented a holder for a roll of picture-carrying gelatin layer-coated paper. [[Hannibal Goodwin]] then invented a [[nitrocellulose]] [[film base]] in 1887, the first transparent, flexible film.<ref>{{cite magazine | url = https://www.wired.com/2011/05/0502celuloid-photographic-film/| date = 2 May 2011 | access-date = 29 August 2017 | first = Randy | last = Alfred | magazine = [[Wired (magazine)|Wired]] | title = May 2, 1887: Celluloid-Film Patent Ignites Long Legal Battle}}</ref><ref>{{cite web |url=https://www.pbs.org/wgbh/amex/eastman/timeline/index_2.html |title=The Wizard of Photography: The Story of George Eastman and How He Transformed Photography |work=Timeline PBS American Experience Online |access-date=July 5, 2006}}</ref> Eastman also produced these components, and his was the first major company to mass-produce such film when, in 1889, Eastman realized that the dry-gelatino-bromide [[emulsion]] could be coated onto this clear base, eliminating the paper.<ref>{{cite book |last=Mees |first=C. E. Kenneth |year=1961 |title=From Dry Plates to Ektachrome Film: A Story of Photographic Research |publisher=Ziff-Davis Publishing |pages=15–16}}</ref>

With the advent of flexible film, [[Thomas Edison]] quickly set out on his invention, the [[Kinetoscope]], which was first shown at the [[Brooklyn Institute of Arts and Sciences]] on May 9, 1893.<ref>{{cite book|last=Robinson|first=David|url=https://archive.org/details/frompeepshowtopa0000robi|title=From peep show to palace: the birth of American film|publisher=Columbia University Press|year=1996|isbn=978-0-231-10338-1|page=[https://archive.org/details/frompeepshowtopa0000robi/page/39 39]|url-access=registration}}</ref> The Kinetoscope was a film loop system intended for one-person viewing.<ref name="hone">{{cite book|url=https://books.google.com/books?id=Z_4VAAAACAAJ|title=Eastman Professional Motion Picture Films|date=June 1, 1983|author=Eastman Kodak Co.|publisher=Sterling|isbn=978-0-87985-477-5}}</ref> Edison, along with assistant [[William Kennedy Dickson]], followed that up with the [[Kinetoscope#Kinetophone|Kinetophone]], which combined the Kinetoscope with Edison's cylinder [[phonograph]]. Beginning in March 1892, Eastman and then, from April 1893 into 1896, New York's Blair Camera Co. supplied Edison with film stock.<ref name="JSMPE Dec 1933">{{cite journal|last=Dickson|first=W. K. L.|date=December 1933|title= A Brief History of the Kinetograph, the Kinetoscope and the Kineto-Phonograph |url=https://archive.org/stream/journalofsociety21socirich#page/434/mode/2up|journal= Journal of the Society of Motion Picture Engineers|volume=21|issue=6|pages=435–455|doi=10.5594/J12965|access-date=March 13, 2012}}</ref><ref name="John Fullerton 3">{{cite book|last1=Fullerton|first1=John|url=https://books.google.com/books?id=9lMAfjLi1LEC|title=Moving images: from Edison to the Webcam|last2=Söderbergh-Widding|first2=Astrid|date=June 2000|publisher=John Libbey & Co Ltd|isbn=978-1-86462-054-2|page=3}}</ref> Dickson is credited as the inventor of 35&nbsp;mm movie film in 1889,<ref name="Belton" /><sup>652</sup> when the Edison company was using Eastman film.<ref name="Belton" /><sup>653–654</sup>{{refn|group=fn|name=dicksonsmpte|The actual dimension of 35&nbsp;mm specified by the [[Society of Motion Picture and Television Engineers|SMPTE]] is {{convert|1.377|+/-|0.001|in}}. The size initially created by Dickson was only 0.075&nbsp;mm narrower than the 35&nbsp;mm standard that has existed since 1930. An account of this is given in an article by Dickson in the December 1933 SMPTE journal. This size was also exactly half the width of the {{convert|2+3/4|in|mm|adj=mid|wide}} "A-type" 120 and 620 rollfilm which was the standard Eastman size at the time. The standard size was increased at the May 1929 meeting of the SMPE and published in 1930.<ref>{{cite web |first=Joe |last=McGloin |url=http://www.subclub.org/shop/halframe.htm |title=Half Frame Cameras |website=The Sub Club |access-date=August 12, 2006}}</ref><ref>{{cite web |url=http://www.eastman.org/fm/mees/htmlsrc/mE12900002_ful.html |title=Enhancing the Illusion: The Process and Origins of Photography |website=George Eastman House |access-date=August 12, 2006 |archive-url=https://web.archive.org/web/20080117183418/http://www.eastman.org/fm/mees/htmlsrc/mE12900002_ful.html |archive-date=17 January 2008}}</ref>}} The company still received film from Blair after this; at first Blair would supply only {{convert|40|mm|frac=16|abbr=on|adj=on}} film stock that would be trimmed and perforated at the Edison lab to create {{convert|1+3/8|in|adj=on}} gauge filmstrips, then at some point in 1894 or 1895, Blair began sending stock to Edison that was cut exactly to specification.<ref name="JSMPE Dec 1933" /><ref name="John Fullerton 3" /> Edison's [[aperture]] defined a single frame of film at four [[Film perforations|perforations]] high.<ref name="katz">{{cite book|last=Katz|first=Ephraim|url=https://archive.org/details/filmencyclopedia0katz|title=The Film Encyclopedia|publisher=HarperCollins|year=1994|isbn=978-0-06-273089-3|url-access=registration}}</ref>

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Around 1896, a 35mm projector known as a "photo-rotoscope" was made by W. C. Hughes in [[London]], which advanced the film by means of a "dog" motion.<ref>{{cite web | title='Photo-rotoscope' 35mm projector mechanism | website=Science Museum Group Collection| url=https://collection.sciencemuseumgroup.org.uk/objects/co18670/photo-rotoscope-35mm-projector-mechanism-35-mm-cine-film-projector | access-date=24 December 2022}}</ref>

For a time, it had been generally assumed that Dickson was following cinematography formats established by Eastman in producing the film, but Eastman had produced film in sheets that were then cut to order.<ref name="Belton" /><sup>652–653</sup> Dickson used the film supplied for [[Eastman Kodak]] cameras in 1889, a transparent [[70 mm film|70&nbsp;mm]] celluloid film, in his development of a more suitable [[film stock]], and "simply slit this film in half";<ref name="Belton" /><sup>653–654</sup> it was initially developed for the Kinetoscope, a one-person viewer, not to be projected.<ref name="Belton" /><sup>658</sup> The image was still of high quality, even when magnified, and was more economical than 70&nbsp;mm film (and more economical than any other gauge, as cutting the 70&nbsp;mm to size would have created waste).<ref name="Belton" /><sup>654</sup> 35&nbsp;mm was immediately accepted as standard by the [[Auguste and Louis Lumière|Lumière brothers]], and became the main film used in the UK because it was the stock sold to these filmmakers by the Blair company.<ref name=Belton>{{cite journal|url=https://ieeexplore.ieee.org/document/7228070|archive-url=https://web.archive.org/web/20180605024653/https://ieeexplore.ieee.org/document/7228070/|url-status=dead|archive-date=June 5, 2018|title=The Origins of 35mm Film as a Standard|last=Belton|first=John|journal= Journal of the Society of Motion Picture and Television Engineers|volume=99|issue=8|date=August 1990|pages=652–661|doi=10.5594/J02613|issn=0036-1682}}</ref><sup>653</sup>

Edison claimed exclusive [[patent]] rights to the design of 35&nbsp;mm motion picture film,{{refn|group=fn|{{US patent|0589168}}}} with four sprocket holes (perforations) per frame, forcing his only major filmmaking competitor, [[American Mutoscope & Biograph]], to use a 68&nbsp;mm film that used friction feed, not sprocket holes, to move the film through the camera. A court judgment in March 1902 invalidated Edison's claim, allowing any producer or distributor to use the Edison 35&nbsp;mm film design without license. Filmmakers were already doing so in Britain and Europe, where Edison did not file patents.<ref>{{cite book |last=Musser |first=Charles |title=The Emergence of Cinema: The American Screen to 1907 |url=https://books.google.com/books?id=IEUMWToGOtUC |year=1994 |publisher=University of California Press |location=Berkeley, California |isbn=978-0-520-08533-6 |pages=303–313}}</ref> At the time, film stock was usually supplied unperforated and punched by the filmmaker to their standards with perforation equipment. A variation developed by the Lumière brothers used a single circular perforation on each side of the frame towards the middle of the horizontal axis.<ref name="lumiere">Lobban, Grant. "Film Gauges and Soundtracks", [[British Kinematograph, Sound and Television Society|BKSTS]] wall chart (sample frame provided). [Year unknown]</ref>

==== Becoming the standard ====
[[File:Dickson&#039;s 35 mm movie film standard and 35 mm patent design.png|thumb|Dickson's 35&nbsp;mm movie film standard (center)]]
When films began to be projected, several projection devices were unsuccessful and fell into obscurity because of technical failure, lack of business acumen on the part of their promoters, or both. The [[Vitascope]], the first projection device to use 35&nbsp;mm, was technologically superior and compatible with the many motion pictures produced on 35&nbsp;mm film. Edison bought the device in 1895–96; the Lumiere's 35&nbsp;mm projection [[Cinematograph]] also premiered in 1895, and they established 35&nbsp;mm as the standard for exhibition.<ref name="Belton" /><sup>658</sup>

Standardization in recording came from monopolization of the business by Eastman and Edison, and because of Edison's typical business model involving the patent system: Eastman and Edison managed their film patents well<ref name="Belton" /><sup>656</sup> – Edison filed the 35&nbsp;mm patent in 1896, the year after Dickson left his employ<ref name="Belton" /><sup>657</sup> – and so controlled the use and development of film.<ref name="Belton" /><sup>656</sup> Dickson left the Edison company in 1895, going on to help competitors produce cameras and other film gauges that would not infringe on [[List of Edison patents|Edison's patents]]. However, by 1900, filmmakers found it too expensive to develop and use other gauges, and went back to using the cheap and widely-available 35&nbsp;mm.<ref name="Belton" /><sup>657</sup>

Dickson said in 1933:
{{quote|At the end of the year 1889, I increased the width of the picture from {{frac||1|2}} inch to {{frac||3|4}} inch, then, to 1 inch by {{frac||3|4}} inch high. The actual width of the film was {{frac|1|3|8}} inches to allow for the perforations now punched on both edges, 4 holes to the phase or picture, which perforations were a shade smaller than those now in use. This standardized film size of 1889 has remained, with only minor variations, unaltered to date.<ref name="Belton" /><sup>652</sup>}}

Until 1953, the 35&nbsp;mm film was seen as "basic technology" in the film industry, rather than optional, despite other gauges being available.<ref name="Belton" /><sup>652</sup>

[[File:35mm film format with optical soundtrack.svg|thumb|upright=1.5|35&nbsp;mm film diagram]]
In 1908, Edison formed "a cartel of production companies", a [[trust (19th century)|trust]] called the [[Motion Picture Patents Company]] (MPPC), pooling patents for collective use in the industry and positioning Edison's own technology as the standard to be licensed out.<ref name="Belton" /><sup>656</sup> 35&nbsp;mm became the "official" standard of the newly formed MPPC, which agreed in 1909 to what would become the standard: 35&nbsp;mm gauge, with Edison perforations and a 1.3{{overline|3}}:1 (4:3) [[aspect ratio (image)|aspect ratio]] (also developed by Dickson).<ref name="Belton" /><sup>652</sup><ref group="fn">The gauge and perforations are almost identical to modern film stock; the full silent ratio is also used as the [[film gate]] in movie cameras, although portions of the image are later cropped out in post-production and projection.</ref> Scholar Paul C. Spehr describes the importance of these developments:

{{quote|The early acceptance of 35&nbsp;mm as a standard had momentous impact on the development and spread of cinema. The standard gauge made it possible for films to be shown in every country of the world&nbsp;... It provided a uniform, reliable and predictable format for production, distribution and exhibition of movies, facilitating the rapid spread and acceptance of the movies as a world-wide device for entertainment and communication.<ref name="John Fullerton 3"/>}}

When the MPPC adopted the 35&nbsp;mm format, [[Bell & Howell]] produced cameras, projectors, and perforators for the medium of an "exceptionally high quality", further cementing it as the standard.<ref name="Belton" /><sup>659</sup> Edison and Eastman's form of business manipulation was ruled unlawful in 1914, but by this time the technology had become the established standard.<ref name="Belton" /><sup>657</sup> In 1917, the new [[Society of Motion Picture and Television Engineers|Society of Motion Picture Engineers]] (SMPE) "acknowledged the de facto status of 35mm as the industry's dominant film gauge, adopting it as an engineering standard".<ref name="Belton" /><sup>659</sup>

===Innovations in sound===
[[File:35mm film audio macro.jpg|thumb|upright=0.9|A photo of a 35&nbsp;mm film print featuring all four audio formats (or "quad track") — from left to right: [[Sony Dynamic Digital Sound|SDDS]], a soundtrack as an image of a digital signal (blue area to the left of the sprocket holes); [[Dolby Digital]] sound (grey area between the sprocket holes labelled with the Dolby "Double-D" logo in the middle); [[Dolby Stereo|analog optical sound]], optically recorded as waveforms containing the audio signals for the left and right audio channels (the two white lines to the right of the sprocket holes); and the [[Digital Theater System|DTS]] [[time code]] (the dashed line to the far right).]]
When film editing was done by physically cutting the film, editing the picture could only have been done on the frame line. However, the sound was stored for the whole frame between each of the four sprocket holes, and so the sound editors could cut on any arbitrary set of holes, and thus get {{frac||1|4}}-frame edit resolution. With this technique, an audio edit could be accurate to within 10.41&nbsp;[[Millisecond|ms]]."<ref name=Rose>{{cite book |hdl=1853/50482 |chapter=Reality (sound)bites: Audio tricks from the film and TV studio |title=International Conference on Auditory Display |last=Rose |first=Jay |date=July 2003}}</ref><sup>1–2</sup> A limitation of [[Analog recording|analog optical recording]] was the audio frequency would cut off, in a well-maintained theater, at around 12[[Hertz|kHz]].<ref name=Rose/><sup>4</sup> Studios would often record audio on the transparent film strips, but with [[magnetic tape]] on one edge; recording audio on full 35&nbsp;mm magnetic tape was more expensive.<ref name=Rose/><sup>5</sup>

Three different digital soundtrack systems for 35&nbsp;mm cinema release prints were introduced during the 1990s. They are: [[Dolby Digital]], which is stored between the perforations on the sound side; [[Sony Dynamic Digital Sound|SDDS]], stored in two [[redundancy (engineering)|redundant]] strips along the outside edges (beyond the perforations); and [[Digital Theatre System|DTS]], in which sound data is stored on separate [[compact disc]]s synchronized by a [[timecode]] track on the film just to the right of the analog soundtrack and left of the frame.<ref>{{cite web |url=http://www.dts.com/Corporate/About_Us/Milestones.aspx |website=DTS |title=Corporate Milestones |url-status=dead |archive-url=https://web.archive.org/web/20100609183206/http://www.dts.com/Corporate/About_Us/Milestones.aspx |archive-date=2010-06-09 }}</ref> Because these soundtrack systems appear on different parts of the film, one movie can contain all of them, allowing broad distribution without regard for the sound system installed at individual theatres.

The analogue optical track technology has also changed: in the early years of the 21st century, distributors changed to using [[cyan]] dye optical soundtracks instead of applicated tracks, which use environmentally unfriendly chemicals to retain a silver (black-and-white) soundtrack. Because traditional [[Incandescent light bulb|incandescent]] [[Optical sound#Film and radio|exciter lamps]] produce copious amounts of [[infrared light]], and cyan tracks do not absorb infrared light, this change has required theaters to replace the incandescent exciter lamp with a complementary colored red [[LED]] or [[Laser light|laser]]. These LED or laser exciters are backwards-compatible with older tracks.<ref name="cyan">{{cite web |last=Hull |first=Joe |url=http://www.dyetracks.org/FJI_Sept04.pdf |title=Committed to Cyan |website=dyetracks.org |access-date=August 11, 2006 |url-status=dead |archive-url=https://web.archive.org/web/20060921125129/http://www.dyetracks.org/FJI_Sept04.pdf |archive-date=September 21, 2006 }}</ref> The film ''[[Anything Else]]'' (2003) was the first to be released with only cyan tracks.<ref name="cyan" />

To facilitate this changeover, intermediate prints known as "high magenta" prints were distributed. These prints used a silver plus dye soundtrack that were printed into the magenta dye layer. The advantage gained was an optical soundtrack, with low levels of sibilant (cross-modulation) distortion, on both types of sound heads.<ref name="kodak-cyan">{{cite web |website=Kodak |url=http://motion.kodak.com/US/en/motion/Support/Technical_Information/Lab_Tools_And_Techniques/Cyan_Dye_Tracks/guide.htm |title=Cyan Dye Tracks Laboratory Guide |url-status=dead |archive-url=https://web.archive.org/web/20091126055003/http://motion.kodak.com/US/en/motion/Support/Technical_Information/Lab_Tools_And_Techniques/Cyan_Dye_Tracks/guide.htm |archive-date=2009-11-26 }}</ref>

===Modern 3D systems===
[[File:Over-Under 3D image.JPG|thumb|An "over-under" 3D frame. Both left and right eye images are contained within the normal height of a single 2D frame.]]
The success of digitally projected 3D movies in the first two decades of the 21st century led to a demand from some theater owners to be able to show these movies in 3D without incurring the high capital cost of installing digital projection equipment. To satisfy that demand, a number of systems had been proposed for 3D systems based on 35&nbsp;mm film by [[Technicolor]],<ref>{{cite web |url=http://www.technicolor.com/en/hi/cinema |title=Entertainment Services |work=Technicolor |access-date=29 August 2016 |archive-url=https://web.archive.org/web/20111024021545/http://www.technicolor.com/en/hi/cinema |archive-date=2011-10-24 |url-status=dead }}</ref> [[Panavision]]<ref>{{cite journal |title=Seeing is Believing |journal=Cinema Technology |volume=24 |number=1 |date=March 2011}}</ref> and others. These systems are improved versions of the [[3-D film#Revival (1960–1984) in single strip format|"over-under" stereo]] 3D prints first introduced in the 1960s.

To be attractive to exhibitors, these schemes offered [[3D film]]s that can be projected by a standard 35&nbsp;mm cinema projector with minimal modification, and so they are based on the use of "over-under" film prints. In these prints a left-right pair of 2.39:1 non-anamorphic images are substituted for the one 2.39:1 anamorphic image of a 2D "scope" print. The frame dimensions are based on those of the [[Techniscope]] 2-perf camera format used in the 1960s and 1970s. However, when used for 3D the left and right frames are pulled down together, thus the standard 4-perf pulldown is retained, minimising the need for modifications to the projector or to long-play systems. The linear speed of film through the projector and sound playback both remain exactly the same as in normal 2D operation.

The Technicolor system uses the polarisation of light to separate the left and right eye images and for this they rent to exhibitors a combination splitter-polarizer-lens assembly which can be fitted to a lens turret in the same manner as an anamorphic lens. In contrast, the Panavision system uses a spectral comb filter system, but their combination splitter-filter-lens is physically similar to the Technicolor assembly and can be used in the same way. No other modifications are required to the projector for either system, though for the Technicolor system a silver screen is necessary, as it would be with polarised-light digital 3D. Thus a programme can readily include both 2D and 3D segments with only the lens needing to be changed between them.

In June 2012, Panavision 3D systems for both 35&nbsp;mm film and digital projection were withdrawn from the market by DVPO theatrical (who marketed these system on behalf of Panavision) citing "challenging global economic and 3D market conditions".<ref>{{cite web |url=http://www.dpvotheatrical.com/Home_Page.html |title=Home |website=DVPO Theatrical |url-status=usurped |archive-url=https://web.archive.org/web/20120407125922/http://www.dpvotheatrical.com/Home_Page.html |archive-date=2012-04-07 }}</ref>

===Decline and resurgence===
In the transition period centered around 2010–2015, the rapid conversion of the cinema exhibition industry to [[digital cinema|digital projection]] saw 35&nbsp;mm film projectors removed from most of the projection rooms as they were replaced by digital projectors. By the mid-2010s, most of the theaters across the world had been converted to digital projection, although a small percentage (under 10% overall) continued running 35&nbsp;mm projectors, mostly indie theaters or those in more economically-challenged regions.<ref>{{cite journal |url=https://variety.com/2013/film/news/digital-cinema-conversion-nears-end-game-1200500975/ |title=Digital Cinema Conversion Nears End Game |first=Leo |last=Barraclough |date=2013-06-23 |journal=[[Variety (magazine)|Variety]] |access-date=2016-08-29 }}</ref> However, it continued as a [[Niche market|niche]] market for enthusiasts and format lovers.<ref name="Houston">{{Cite web |last=Lindsey |first=Craig D. |date=January 24, 2025 |title=Houston film lovers get a nostalgic treat with 35mm screenings at MFAH |url=https://houston.culturemap.com/news/entertainment/35mm-film-projection-mfah/ |access-date=March 19, 2025 |website=CultureMap Houston}}</ref>

In the [[2020s in film|2020s]], 35&nbsp;mm has seen some resurgence in usage. The resurgence comes from those who find 35&nbsp;mm to be more visually pleasing and evoke nostalgic feelings, as well as a desire from young [[Millennials]] and [[Generation Z]] filmmakers and photographers to preserve the art.<ref>{{Cite web |last=Wakim |first=Olivia |date=August 1, 2023 |title=After years of decline, film photography on the upswing |url=https://www.ajc.com/things-to-do/after-years-of-decline-film-photography-on-the-upswing/IHUISNRCENH3NMPMNUAD7LDNPE/ |access-date=March 19, 2025 |website=[[The Atlanta Journal-Constitution]]}}</ref> Several films such as ''[[Oppenheimer (film)|Oppenheimer]]'' and ''[[Anora]]'' have been produced using 35&nbsp;mm film. In an effort to rebuild business lost during the [[COVID-19 pandemic]], some theaters have used special event screenings of films with 35&nbsp;mm film projectors to attract customers. Most of these screenings occur in large metropolitan areas.<ref name="Houston" /><ref>{{Cite web |date=March 8, 2025 |title=Oscar best picture winner gets new life on old film at Atlanta theater |url=https://www.ajc.com/things-to-do/anora-screens-on-35-mm-film-at-atlanta-tara-theatre/4CD4YUC2JNCBVJ7PLL5ZPGZWZ4/ |access-date=March 19, 2025 |website=[[The Atlanta Journal-Constitution]]}}</ref>

==Attributes==
===Color===
{{Main|Color motion picture film}}
Originally, film was a strip of cellulose nitrate coated with black-and-white [[photographic emulsion]].<ref name="hone" /> Early film pioneers, like [[D. W. Griffith]], color [[film tinting|tinted or toned]] portions of their movies for dramatic impact, and by 1920, 80 to 90 percent of all films were tinted.<ref>{{cite book |last=Koszarski |first=Richard |title=An Evening's Entertainment: The Age of the Silent Feature Picture, 1915–1928 |url=https://books.google.com/books?id=PLUbxH1_PREC |date=May 4, 1994 |publisher=University of California Press |isbn=978-0-520-08535-0 |page=127}}</ref> The first successful natural color process was Britain's [[Kinemacolor]] (1909–1915), a two-color additive process that used a rotating disk with red and green filters in front of the [[camera lens]] and the projector lens.<ref name=":2">{{Cite book |last=McKernan |first=Luke |title=Charles Urban: Pioneering the Non-Fiction Film in Britain and America, 1897-1925 |publisher=University of Exeter Press |year=2018 |isbn=978-0859892964}}</ref><ref>{{cite book |last=Robertson |first=Patrick |title=Film Facts |url=https://books.google.com/books?id=4PnEvNC_F9oC |date=September 1, 2001 |publisher=[[Billboard Books]] |location=New York |isbn=978-0-8230-7943-8 |page=166}}</ref><ref>{{cite web |last=Hart |first=Martin |year=1998 |url=http://www.widescreenmuseum.com/oldcolor/kinemaco.htm |title=Kinemacolor: The First Successful Color System |website=[[Widescreen Museum]] |access-date=July 8, 2006}}</ref> But any process that photographed and projected the colors sequentially was subject to color "fringing" around moving objects, and a general color flickering.<ref>{{cite web |last=Hart |first=Martin |date=May 20, 2004 |url=http://www.widescreenmuseum.com/oldcolor/kinemacolortoeastmancolor.htm |title=Kinemacolor to Eastmancolor: Faithfully Capturing an Old Technology with a Modern One |website=Widescreen Museum |access-date=July 8, 2006}}</ref>

In 1916, William Van Doren Kelley began developing [[Prizma]], the first commercially viable American color process using 35&nbsp;mm film. Initially, like Kinemacolor, it photographed the color elements one after the other and projected the results by [[additive color|additive synthesis]]. Ultimately, Prizma was refined to [[bipack]] photography, with two strips of film, one treated to be sensitive to red and the other not, running through the camera face to face. Each negative was printed on one surface of the same [[Duplitized film|duplitized print stock]] and each resulting series of black-and-white images was chemically toned to transform the silver into a monochrome color, either orange-red or blue-green, resulting in a two-sided, two-colored print that could be shown with any ordinary projector. This system of two-color bipack photography and two-sided prints was the basis for many later color processes, such as [[Multicolor]], [[Brewster Color]] and [[Cinecolor]].

Although it had been available previously, color in Hollywood feature films first became truly practical from the studios' commercial perspective with the advent of [[Technicolor]], whose main advantage was quality prints in less time than its competitors. In its earliest incarnations, Technicolor was another two-color system that could reproduce a range of reds, muted bluish greens, pinks, browns, tans and grays, but not real blues or yellows. ''[[The Toll of the Sea]]'', released in 1922, was the first film printed in their subtractive color system. Technicolor's camera photographed each pair of color-filtered frames simultaneously on one strip of black-and-white film by means of a [[beam splitter]] prism behind the camera lens. Two prints on half-thickness stock were made from the negative, one from only the red-filtered frames, the other from the green-filtered frames. After development, the silver images on the prints were chemically toned to convert them into images of the approximately [[complementary color]]s. The two strips were then cemented together back to back, forming a single strip similar to duplitized film.

In 1928, [[Technicolor]] started making their prints by the imbibition process, which was mechanical rather than photographic and allowed the color components to be combined on the same side of the film. Using two matrix films bearing hardened gelatin relief images, thicker where the image was darker, aniline color dyes were transferred into the gelatin coating on a third, blank strip of film.

Technicolor re-emerged as a three-color process for [[cartoons]] in 1932 and [[live action]] in 1934. Using a different arrangement of a [[beam-splitter]] cube and color filters behind the lens, the camera simultaneously exposed three individual strips of black-and-white film, each one recording one-third of the [[visible spectrum|spectrum]], which allowed virtually the entire spectrum of colors to be reproduced.<ref name="widetech">{{cite web |last=Hart |first=Martin |year=2003 |url=http://www.widescreenmuseum.com/oldcolor/technicolor1.htm |title=The History of Technicolor |website=Widescreen Museum |access-date=July 7, 2006}}</ref> A printing matrix with a hardened gelatin relief image was made from each negative, and the three matrices transferred color dyes into a blank film to create the print.<ref>{{cite book |last=Sipley |first=Louis Walton |year=1951 |title=A Half Century of Color |publisher=The Macmillan Company |location=New York}}</ref>

Two-color processes, however, were far from extinct. In 1934, William T. Crispinel and Alan M. Gundelfinger revived the [[Multicolor]] process under the company name [[Cinecolor]]. Cinecolor saw considerable use in animation and low-budget pictures, mainly because it cost much less than three-color Technicolor. If color design was carefully managed, the lack of colors such as true green could pass unnoticed. Although Cinecolor used the same duplitized stock as Prizma and Multicolor, it had the advantage that its printing and processing methods yielded larger quantities of finished film in less time.

In 1950, Kodak announced the first Eastman color 35&nbsp;mm negative film (along with a complementary positive film) that could record all three primary colors on the same strip of film.<ref>{{cite web|work=Kodak |title=Chronology of Motion Picture Films 1940 to 1959 |url=http://motion.kodak.com/US/en/motion/Products/Chronology_Of_Film/chrono2.htm |access-date=August 12, 2009 |archive-url=https://web.archive.org/web/20090625062139/http://motion.kodak.com/US/en/motion/Products/Chronology_Of_Film/chrono2.htm |archive-date=June 25, 2009 |url-status=dead }}</ref> An improved version in 1952 was quickly adopted by Hollywood, making the use of three-strip Technicolor cameras and bipack cameras (used in two-color systems such as [[Cinecolor]]) obsolete in color cinematography. This "monopack" structure is made up of three separate emulsion layers, one sensitive to red light, one to green and one to blue.

===Safety film===
{{Main|Safety film}}
Although [[Eastman Kodak]] had first introduced [[acetate]]-based film, it was far too brittle and prone to shrinkage, so the dangerously flammable nitrate-based cellulose films were generally used for motion picture camera and print films. In 1949 Kodak began replacing all nitrocellulose (nitrate-based) films with the safer, more robust [[cellulose triacetate]]-based "Safety" films. In 1950 the [[Academy of Motion Picture Arts and Sciences]] awarded Kodak with a Scientific and Technical [[Academy Award]] ([[Academy Awards|Oscar]]) for the safer triacetate stock.<ref>{{cite web|url=http://www.kodak.com/global/en/corp/historyOfKodak/impacting.jhtml?pq-path=2217/2687/2691 |title=Broadening the Impact of Pictures |work=Kodak.com |access-date=August 29, 2016 |url-status=dead |archive-url=https://web.archive.org/web/20120201104103/http://www.kodak.com/global/en/corp/historyOfKodak/impacting.jhtml?pq-path=2217%2F2687%2F2691 |archive-date=February 1, 2012 }}</ref> By 1952, all camera and projector films were triacetate-based.<ref name="tafi">{{cite book|last=Slide|first=Anthony|url=https://books.google.com/books?id=DO8JAQAAMAAJ|title=The American film industry: a historical dictionary|publisher=Amadeus Press|year=1990|isbn=978-0-87910-139-8}}</ref> Most if not all film prints today are made from synthetic [[polyester]] safety base (which started replacing Triacetate film for prints in the early 1990s). The downside of [[polyester]] film is that it is extremely strong, and, in case of a fault, will stretch and not break–potentially causing damage to the projector and ruining a fairly large stretch of film: 2–3&nbsp;ft or approximately 2&nbsp;seconds. Also, polyester film will melt if exposed to the projector lamp for too long. [[Original camera negative]] is still made on a triacetate base, and some intermediate films (certainly including internegatives or "dupe" negatives, but not necessarily including interpositives or "master" positives) are also made on a triacetate base as such films must be spliced during the "negative assembly" process, and the extant negative assembly process is solvent-based. Polyester films are not compatible with solvent-based assembly processes.

===Other types===
Besides black & white and color negative films, there are black & white and color [[reversal film]]s, which when developed create a positive ("natural") image that is projectable. There are also films sensitive to non-visible [[Light wavelength|wavelengths of light]], such as [[Infrared photography|infrared]].<ref>{{Cite web |title=This Month in Physics History |url=https://www.aps.org/archives/publications/apsnews/201710/physicshistory.cfm |access-date=2025-03-07 |website=www.aps.org |language=en}}</ref>

==Common formats==
{{main list|List of film formats}}

===Academy format===
{{Main|Academy ratio}}
[[File:35 mm film (Academy Ratio).svg|thumb|right|upright=1.5|Academy Ratio (4-perf) format diagram]]
In the conventional motion picture format, frames are four perforations tall, with an [[aspect ratio (image)|aspect ratio]] of 1.375:1, {{convert|22|by|16|mm|in|3|abbr=on}}. This is a derivation of the aspect ratio and frame size designated by Thomas Edison ({{convert|24.89|by|18.67|mm|disp=or}}) at the dawn of motion pictures, which was an aspect ratio of 1.33:1.<ref>{{cite book|last=Belton|first=John |title=Widescreen Cinema |url=https://books.google.com/books?id=PKUfAQAAIAAJ |year=1992 |publisher=Harvard University Press |location=Cambridge, Mass. |isbn=978-0-674-95261-4 |pages=17–18}}</ref> The first sound features were released in 1926–27, and while [[Warner Bros.]] was using synchronized phonograph discs ([[sound-on-disc]]), [[Fox Film Corporation|Fox]] placed the soundtrack in an optical record directly on the film ([[sound-on-film]]) on a strip between the sprocket holes and the image frame.<ref name="early sound">{{cite book |last=Dibbets |first=Karel |chapter=The Introduction of Sound |title=The Oxford History of World Cinema |publisher=Oxford University Press |location=Oxford |year=1996}}</ref> "Sound-on-film" was soon adopted by the other Hollywood studios, resulting in an almost square image ratio of 0.860&nbsp;in by 0.820&nbsp;in.<ref name="SMPE1930">{{cite journal |last=Cowan |first=Lester |title=Camera and Projector Apertures in Relation to Sound on Film Pictures |journal= Journal of the Society of Motion Picture Engineers|volume=14 |date=January 1930 |pages=108–121|doi=10.5594/J14828 }}</ref>

By 1929, most movie studios had revamped this format using their own house aperture plate size to try to recreate the older screen ratio of 1.33:1. Furthermore, every theater chain had their own house aperture plate size in which the picture was projected. These sizes often did not match up even between theaters and studios owned by the same company, and therefore, uneven projection practices occurred.<ref name="SMPE1930"/>

In November 1929, the [[Society of Motion Picture Engineers]] set a standard aperture ratio of 0.800&nbsp;in by 0.600&nbsp;in. Known as the "1930 standard", studios which followed the suggested practice of marking their camera viewfinders for this ratio were: Paramount-Famous-Lasky, Metro-Goldwyn Mayer, United Artists, Pathe, Universal, RKO, Tiffany-Stahl, Mack Sennett, Darmour, and Educational. The Fox Studio markings were the same width but allowed .04&nbsp;in more height.<ref>{{cite journal |title=Studios Seek to Aid Towards Better Projection Goal |journal=Movie Age |date=November 9, 1929 |page=18}}</ref>

In 1932, in refining this ratio, the [[Academy of Motion Picture Arts and Sciences]] expanded upon this 1930 standard. The camera aperture became {{convert|22|by|16|mm|in|abbr=on}}, and the projected image would use an aperture plate size of {{convert|0.825|by|0.600|in|mm|abbr=on}}, yielding an aspect ratio of 1.375:1. This became known as the "[[Academy ratio|Academy]]" ratio.<ref name="1.375">{{cite book|editor-last=Hummel|editor-first=Rob |title=American Cinematographer Manual |edition=8th |pages=18–22 |publisher=ASC Press |location=Hollywood |year=2001}}</ref> Since the 1950s the aspect ratio of some theatrically released motion picture films has been 1.85:1 (1.66:1 in Europe) or 2.35:1 (2.40:1 after 1970). The image area for "TV transmission" is slightly smaller than the full "Academy" ratio at {{convert|21|by|16|mm|in|abbr=on}}, an aspect ratio of 1.33:1. Hence when the "Academy" ratio is referred to as having an aspect ratio of 1.33:1, it is done so mistakenly.<ref name="1.375" />

===Widescreen===
{{Main|Anamorphic|Aspect ratio (image)|Widescreen}}
[[File:35 mm film (CinemaScope).svg|thumb|right|upright=1.5|CinemaScope (2.39:1, flat and anamorphic) format diagram]]
The commonly used [[anamorphic]] format uses a similar four-perf frame, but an anamorphic lens is used on the camera and projector to produce a wider image, today with an aspect ratio of about 2.39:1 (more commonly referred to as 2.40:1). The ratio was formerly 2.35:1—and is still often mistakenly referred to as such—until an [[SMPTE]] revision of projection standards in 1970.<ref name="2.39">{{cite web |last=Hart |first=Martin |year=2000 |website=Widescreen Museum |url=http://www.widescreenmuseum.com/widescreen/apertures.htm |title=Of Apertures and Aspect Ratios |access-date=August 10, 2006}}</ref> The image, as recorded on the negative and print, is horizontally compressed (squeezed) by a factor of 2.<ref name="ana">{{cite book |last=Hora |first=John |chapter=Anamorphic Cinematography |title=American Cinematographer Manual |edition=8th |publisher=ASC Press |location=Hollywood |year=2001}}</ref>

The unexpected success of the [[Cinerama]] widescreen process in 1952 led to a boom in [[film format]] innovations to compete with the growing audiences of television and the dwindling audiences in movie theaters. These processes could give theatergoers an experience that television could not at that time—color, stereophonic sound and panoramic vision. Before the end of the year, [[20th Century Fox]] had narrowly "won" a race to obtain an [[anamorphic]] optical system invented by [[Henri Chrétien]], and soon began promoting the [[Cinemascope]] technology as early as the production phase.<ref name="scope">{{cite web |last=Hart |first=Martin |year=2000 |website=Widescreen Museum |url=http://www.widescreenmuseum.com/widescreen/wingcs1.htm |title=Cinemascope Wing 1 |access-date=August 10, 2006}}</ref>

[[File:35 mm film (Widescreen).svg|thumb|right|upright=1.5|Widescreen (1.85:1, flat and anamorphic) format diagram]]
Looking for a similar alternative, other major studios hit upon a simpler, less expensive solution by April 1953: the camera and projector used conventional spherical lenses (rather than much more expensive anamorphic lenses), but by using a removable aperture plate in the film projector gate, the top and bottom of the frame could be cropped to create a wider aspect ratio. Paramount Pictures began this trend with their aspect ratio of 1.66:1, first used in ''[[Shane (film)|Shane]]'', which was originally shot for [[Academy ratio]].<ref name="crop">{{cite web |last=Hart |first=Martin |year=2000 |website=Widescreen Museum |url=http://www.widescreenmuseum.com/Widescreen/evolution.htm |title=Early Evolution from Academy to Wide Screen Ratios |access-date=August 10, 2006}}</ref> It was Universal Studios, however, with their May release of ''[[Thunder Bay (film)|Thunder Bay]]'' that introduced the now standard 1.85:1 format to American audiences and brought attention to the industry the capability and low cost of equipping theaters for this transition.

Other studios followed suit with aspect ratios of 1.75:1 up to 2:1. For a time, these various ratios were used by different studios in different productions, but by 1956, the aspect ratio of 1.85:1 became the "standard" US format. These ''flat'' films are photographed with the full [[Academy ratio|Academy frame]], but are [[Matte (filmmaking)|matted]] (most often with a [[Masking (art)|mask]] in the theater projector, not in the camera) to obtain the "wide" aspect ratio. The standard, in some European countries, became 1.66:1 instead of 1.85:1, although some productions with pre-determined American distributors composed for the latter to appeal to US markets.

In September 1953, 20th Century Fox debuted CinemaScope with their production of ''[[The Robe (film)|The Robe]]'' to great success.<ref>{{cite journal|last=Samuelson |first=David W. |date=September 2003 |title=Golden Years |journal=American Cinematographer Magazine |publisher=ASC Press |pages=70–77}}</ref> CinemaScope became the first marketable usage of an anamorphic widescreen process and became the basis for a host of "formats", usually suffixed with ''-scope,'' that were otherwise identical in specification, although sometimes inferior in optical quality. (Some developments, such as SuperScope and [[Techniscope]], however, were truly entirely different formats.) By the early 1960s, however, [[Panavision]] would eventually solve many of the CinemaScope lenses' technical limitations with their own lenses,<ref name="ana" /> and by 1967, CinemaScope was replaced by Panavision and other third-party manufacturers.<ref name="obsolete">{{cite book |editor-last=Nowell-Smith |editor-first=Geoffrey |title=The Oxford History of World Cinema |url=https://archive.org/details/oxfordhistoryofw00geof |url-access=registration |page=[https://archive.org/details/oxfordhistoryofw00geof/page/266 266] |publisher=Oxford University Press |location=Oxford |year=1996}}</ref>

The 1950s and 1960s saw many other novel processes using 35&nbsp;mm, such as [[Vistavision|VistaVision]], SuperScope, and [[Technirama]], most of which ultimately became obsolete. VistaVision, however, would be revived decades later by [[Lucasfilm]] and other studios for special effects work, while a SuperScope variant became the predecessor to the modern [[Super 35]] format that is popular today.

===Super 35===
{{Main|Super 35}}
[[File:35 mm film (Super 35).svg|thumb|right|upright=1.5|Super 35 format diagram]]
The concept behind Super 35 originated with the Tushinsky Brothers' SuperScope format, particularly the SuperScope 235 specification from 1956. In 1982, Joe Dunton revived the format for ''[[Dance Craze]]'', and [[Technicolor]] soon marketed it under the name "Super Techniscope" before the industry settled on the name Super 35.<ref name="dunton">{{cite journal |last=Mitchell |first=Rick |journal=Society of Camera Operators Magazine |url=http://www.soc.org/opcam/04_s94/mg04_widescreen.html |title=The Widescreen Revolution: Expanding Horizons — The Spherical Campaign |issue=Summer 1994 |archive-url=https://web.archive.org/web/20040103160036/http://www.soc.org/opcam/04_s94/mg04_widescreen.html |archive-date=January 3, 2004 |url-status=dead |access-date=August 25, 2016}}</ref> The central driving idea behind the process is to return to shooting in the original silent "Edison" 1.33:1 full 4-perf negative area ({{convert|24.89|by|18.67|mm|disp=or}}), and then crop the frame either from the bottom or the center (like 1.85:1) to create a 2.40:1 aspect ratio (matching that of anamorphic lenses) with an area of {{convert|24|by|10|mm|in|abbr=on}}. Although this cropping may seem extreme, by expanding the negative area out perf-to-perf, Super 35 creates a 2.40:1 aspect ratio with an overall negative area of {{convert|240|mm2}}, only {{convert|9|mm2}} less than the 1.85:1 crop of the Academy frame ({{convert|248.81|mm2|disp=or}}).<ref name="asc">{{cite book|first=Stephen H.|last=Burum |title=American Cinematographer Manual |url=https://books.google.com/books?id=kTmGAQAACAAJ |year=2004 |publisher=A.S.C. Holding Corp |isbn=978-0-935578-24-9}}</ref> The cropped frame is then converted at the intermediate stage to a 4-perf anamorphically squeezed print compatible with the anamorphic projection standard. This allows an "anamorphic" frame to be captured with non-anamorphic lenses, which are much more common.{{Citation needed|date=August 2009}} Up to 2000, once the film was photographed in Super 35, an optical printer was used to anamorphose (squeeze) the image. This optical step reduced the overall quality of the image and made Super 35 a controversial subject among cinematographers, many who preferred the higher image quality and frame negative area of anamorphic photography (especially with regard to [[Film grain|granularity]]).<ref name="asc" /> With the advent of [[digital intermediate]]s (DI) at the beginning of the 21st century, however, Super 35 photography has become even more popular, since everything could be done digitally, scanning the original 4-perf 1.33:1 (or 3-perf 1.78:1) picture and cropping it to the 2.39:1 frame already in-computer, without anamorphosing stages, and also without creating an additional optical generation with increased grain. This process of creating the aspect ratio in the computer allows the studios to perform all post-production and editing of the movie in its original aspect (1.33:1 or 1.78:1) and to then release the cropped version, while still having the original when necessary (for Pan & Scan, HDTV transmission, etc.).

===3-perf===
{{Main|Negative pulldown}}
[[File:35 mm film (3-Perf Super 35).svg|thumb|right|upright=1.5|3-perf Super 35 format diagram]]
The non-anamorphic widescreen ratios (most commonly 1.85:1) used in modern feature films makes inefficient use of the available image area on 35&nbsp;mm film using the standard 4-perf pulldown; the height of a 1.85:1 frame occupying only 65% of the distance between the frames. It is clear, therefore, that a change to a 3-perf pulldown would allow for a 25% reduction in film consumption whilst still accommodating the full 1.85:1 frame. Ever since the introduction of these widescreen formats in the 1950s various film directors and cinematographers have argued in favour of the industry making such a change. The Canadian cinematographer Miklos Lente invented and patented a three-perforation pull down system which he called "Trilent 35" in 1975 though he was unable to persuade the industry to adopt it.<ref>{{cite journal |title=Trilent 35 System |journal=Image Technology |volume=70 |number=7 |date=July 1988}}</ref>

The idea was later taken up by the Swedish film-maker Rune Ericson who was a strong advocate for the 3-perf system.<ref>{{cite journal |title=Three Perfs for Four |first=Rune |last=Ericson |journal=Image Technology |volume=69 |number=3 |date=March 1987}}</ref> Ericson shot his 51st feature ''Pirates of the Lake'' in 1986 using two Panaflex cameras modified to 3-perf pulldown and suggested that the industry could change over completely over the course of ten-years. However, the movie industry did not make the change mainly because it would have required the modification of the thousands of existing 35&nbsp;mm projectors in movie theaters all over the world. Whilst it would have been possible to shoot in 3-perf and then convert to standard 4-perf for release prints the extra complications this would cause and the additional optical printing stage required made this an unattractive option at the time for most film makers.

However, in [[television]] [[Film production|production]], where compatibility with an installed base of 35&nbsp;mm film projectors is unnecessary, the [[3-perf]] format is sometimes used, giving—if used with [[Super 35]]—the 16:9 ratio used by [[High-definition television|HDTV]] and reducing film usage by 25 percent. Because of 3-perf's incompatibility with standard 4-perf equipment, it can utilize the whole negative area between the perforations ([[Super 35 mm film|Super 35]]) without worrying about compatibility with existing equipment; the Super 35 image area includes what would be the soundtrack area in a standard print.<ref name="aaton">{{cite web |title=3 perf: The future of 35mm filmmaking |url=http://www.aaton.com/products/film/35/3perf.php |website=[[Aaton]] |access-date=August 10, 2006 |url-status=dead |archive-url=https://web.archive.org/web/20060713061542/http://www.aaton.com/products/film/35/3perf.php |archive-date=July 13, 2006 }}</ref> All 3-perf negatives require optical or digital conversion to standard 4-perf if a film print is desired, though 3-perf can easily be transferred to video with little to no difficulty by modern [[telecine]] or [[Motion picture film scanner|film scanners]]. With digital intermediate now a standard process for feature film post-production, 3-perf is becoming increasingly popular for feature film productions which would otherwise be averse to an optical conversion stage.{{Citation needed|date=August 2009}}<ref>{{cite web|url=http://motion.kodak.com/motion/uploadedFiles/US_plugins_acrobat_en_motion_newsletters_filmEss_05_Film_Types_and_Formats.pdf |title=Film Types_and Formats |website=kodak.com |url-status=dead |archive-url=https://web.archive.org/web/20130601172936/http://motion.kodak.com/motion/uploadedFiles/US_plugins_acrobat_en_motion_newsletters_filmEss_05_Film_Types_and_Formats.pdf |archive-date=2013-06-01 }}</ref>

===VistaVision===
{{Main|VistaVision}}
[[File:35 mm film (8-perf VistaVision).svg|thumb|right|upright=1.76|A diagram of the [[VistaVision]] format, affectionately dubbed "Lazy 8" because it is eight [[film perforations|perforations]] long and runs horizontally (lying down)]] 
The [[VistaVision]] motion picture format was created in 1954 by [[Paramount Pictures]] to create a finer-grained negative and print for flat widescreen films.<ref name="vista">{{cite book |editor-last=Nowell-Smith |editor-first=Geoffrey |title=The Oxford History of World Cinema |url=https://archive.org/details/oxfordhistoryofw00geof |url-access=registration |pages=[https://archive.org/details/oxfordhistoryofw00geof/page/446 446–449] |publisher=Oxford University Press |location=Oxford |year=1996}}</ref> Similar to still photography, the format uses a camera running 35&nbsp;mm film horizontally instead of vertically through the camera, with frames that are eight perforations long, resulting in a wider aspect ratio of 1.5:1 and greater detail, as more of the negative area is used per frame.<ref name="asc" /> This format is unprojectable in standard theaters and requires an optical step to reduce the image into the standard 4-perf vertical 35&nbsp;mm frame.<ref name="achart">{{cite book |last=Hart |first=Douglas C. |title=The Camera Assistant: A Complete Professional Handbook |publisher=Focal Press |location=Boston |year=1996 |url=https://archive.org/details/cameraassistantc0000hart |isbn=0-240-80042-7}}</ref>

While the format was dormant by the early 1960s, the camera system was revived for visual effects by [[John Dykstra]] at [[Industrial Light and Magic]], starting with ''[[Star Wars (film)|Star Wars]]'', as a way of reducing granularity in the [[optical printer]] by having increased [[original camera negative]] area at the point of image origination.<ref name="starwars">{{cite journal |last1=Blalack |first1=Robert |first2=Paul |last2=Roth |title=Composite Optical and Photographic Effects |journal=American Cinematographer Magazine |date=July 1977}}</ref> Its usage has again declined since the dominance of computer-based visual effects, although it still sees limited utilization.<ref name="batman">{{cite web|url=http://www.fxguide.com/article262.html |title=Double Negative Breaks Down ''Batman Begins'' |website=FXGuide |date=July 18, 2005 | access-date=August 11, 2006 |url-status=dead |archive-url=https://web.archive.org/web/20061016104400/http://www.fxguide.com/article262.html |archive-date=October 16, 2006 }}</ref>

==Perforations==
{{Main|Film perforations}}
[[File:35mm Film Sprockets.svg|right|thumb|35&nbsp;mm film perforation hole types.]]

===BH perforations=== 
Film perforations were originally round holes cut into the side of the film, but as these perforations were subject to wear and deformation, the shape was changed to what is now called the [[Böwe Bell & Howell|Bell & Howell]] (BH) perforation, which has straight top and bottom edges and outward curving sides. The BH perforation's dimensions are {{convert|0.110|in|mm}} from the middle of the side curve to opposite top corner by {{convert|0.073|in|mm}} in height.<ref name="case">{{cite book |last= Case |first=Dominic |title=Motion Picture Film Processing |location=Boston |publisher=Focal Press |year=1985 |isbn = 9780240512433}}</ref> The BH1866 perforation, or BH perforation with a [[Film perforations#Pitch|pitch]] of {{convert |0.1866|in|mm}}, is the modern standard for negative and internegative films.<ref name="Kodak motion film specs">{{cite web|url=http://motion.kodak.com/motion/uploadedFiles/US_plugins_acrobat_en_motion_newsletters_filmEss_11_Film_Specs.pdf#page=3 |archive-url=https://web.archive.org/web/20110107142747/http://motion.kodak.com/motion/uploadedFiles/US_plugins_acrobat_en_motion_newsletters_filmEss_11_Film_Specs.pdf |archive-date=2011-01-07 |url-status=live |title=Perforation Sizes and Shapes |publisher=[[Kodak]] |work=Motion Newsletters |date=October 30, 2007 |access-date=March 14, 2012 |page=95}}</ref>

===KS perforations===
Because BH has sharp corners, the repeated use of the film through intermittent movement projectors creates strain that can easily tear the perforations. Furthermore, they tended to shrink as the print slowly decayed. Therefore, larger perforations with a rectangular base and rounded corners were introduced by [[Kodak]] in 1924 to improve steadiness, registration, durability, and longevity. Known as "Kodak Standard" (KS), they are {{convert|0.0780|in|mm}} high by {{convert|0.1100|in|mm}} wide.<ref name="smpte139">{{cite book|title=ST 139:2003 - SMPTE Standard - For Motion-Picture Film (35-mm) — Perforated KS|date=12 November 2003|publisher=[[SMPTE]]|isbn=978-1-61482-313-1|doi=10.5594/SMPTE.ST139.2003}}</ref> Their durability makes KS perfs the ideal choice for some (but not all) intermediate and all release prints, and [[original camera negative]]s which require special use, such as high-speed filming, but not for [[Chroma key|bluescreen]], [[front projection]], [[rear projection]], or [[Matte (filmmaking)|matte]] work as these specific applications demand the more accurate registration which is only possible with BH or DH perforations. The increased height also means that the image registration was considerably less accurate than BH perfs, which remains the standard for negatives.<ref name="JSMPE May 1930">{{cite journal |author=Society of Motion Picture Engineers |date=May 1930 |title=Standards Adopted by the Society of Motion Picture Engineers |url=https://archive.org/stream/journalofsociety14socirich#page/552/mode/2up |journal=Journal of the Society of Motion Picture Engineers |volume=XIV |issue=5 |pages=545–566}}</ref><ref name="screensound">{{cite web |work=ScreenSound Australia |url=http://www.nfsa.afc.gov.au/preservation/audiovisual_terms/audiovisual_item.php?term=Perforations |title=Technical Glossary of Common Audiovisual Terms: Perforations |access-date=August 11, 2006 |archive-url=https://web.archive.org/web/20071031093815/http://www.nfsa.afc.gov.au/preservation/audiovisual_terms/audiovisual_item.php?term=Perforations |archive-date=October 31, 2007}}</ref> The KS1870 perforation, or KS perforation with a [[Film perforations#Pitch|pitch]] of {{convert|0.1870|in|mm}}, is the modern standard for release prints.<ref name="Kodak motion film specs" />

These two perforations have remained by far the most commonly used ones. BH perforations are also known as ''N'' (negative) and KS as ''P'' (positive). The Bell & Howell perf remains the standard for camera negative films because of its perforation dimensions in comparison to most printers, thus it can keep a steady image compared to other perforations.<ref name="Kodak motion film specs" /><ref name="gray">{{cite web |url=http://www.jkor.com/peter/perfs.html |title=Perforations/Sprocket Holes: Peter Gray - Director of Photography |year=1997 |access-date=March 14, 2012 |last=Gray |first=Peter |archive-url=https://web.archive.org/web/20080412041026/http://www.jkor.com/peter/perfs.html |archive-date=April 12, 2008}}</ref>

===DH perforations===
The Dubray–Howell (DH) perforation was first proposed in 1932<ref name="JSMPE April 1932">{{cite journal |url=https://archive.org/stream/journalofsociety18socirich#page/n513/mode/2up |title=Change in 355 Mm. Film Perforations |last=Howell |first=A.S. |journal=Journal of the Society of Motion Picture Engineers |date=April 1932 |volume=XVIII |issue=4 |oclc=1951231}}</ref><ref name="JSMPE Sept 1931">{{cite journal |url=https://archive.org/stream/journalofsociety17socirich#page/432/mode/2up |title=Committee Activities, Report of the Standards and Nomenclature Committee, Wide Film |journal=Journal of the Society of Motion Picture Engineers |date=September 1931 |volume=XVII |issue=3 |pages=431–436 |oclc=1951231 |publisher=The Society |location=New York, NY}}</ref> to replace the two perfs with a single hybrid. The proposed standard was, like KS, rectangular with rounded corners and a width of {{convert|0.1100|in|mm}}, and, like BH, was {{convert|0.073|in|mm}} tall.<ref name="achart" /><ref name="Kodak FAQ Sound Negative">{{cite web |url=http://motion.kodak.com/motion/Support/Technical_Information/Processing_Information/perforations.htm |title=Why Do Sound Negative Films Use Kodak Standard Perforations? |publisher=Kodak |work=Technical Information |access-date=March 14, 2012 |archive-url=https://web.archive.org/web/20120303172050/http://motion.kodak.com/motion/Support/Technical_Information/Processing_Information/perforations.htm |url-status=dead |archive-date=March 3, 2012}}</ref> This gave it longer projection life but also improved registration. One of its primary applications was usage in [[Technicolor]]'s dye imbibition printing (dye transfer).<ref name="gray" /> The DH perf never had broad uptake, and Kodak's introduction of monopack Eastmancolor film in the 1950s reduced the demand for dye transfer,<ref name="screensound" /> although the DH perforation persists in special application intermediate films.<ref name="dh">{{cite web |website=Eastman Kodak |url=http://www.kodak.com/US/en/motion/products/intermediate/tech5242.jhtml?id=0.1.4.6.4.4.4&lc=en |title=Kodak Vision Color Intermediate Film - Technical Data |access-date=August 11, 2006 |url-status=dead |archive-url=https://web.archive.org/web/20060905085939/http://www.kodak.com/US/en/motion/products/intermediate/tech5242.jhtml?id=0.1.4.6.4.4.4&lc=en |archive-date=September 5, 2006 }}</ref>

===CS perforations===
In 1953, the introduction of [[CinemaScope]] by [[20th Century Fox#Twentieth Century/Fox merger|Fox Studios]] required the creation of a different shape of perforation which was nearly square and smaller to provide space for four magnetic sound stripes for stereophonic and surround sound.<ref name="hone" /> These perforations are commonly referred to as CinemaScope (CS) or "Fox hole" perfs. Their dimensions are {{convert|0.0780|in|mm}} in width by {{convert|0.0730|in|mm}} in height.<ref name="smpte102">{{cite book |title=ST 102:2002 - SMPTE Standard - For Motion-Picture Film (35-mm) — Perforated CS-1870 |date=26 July 2002 |doi=10.5594/SMPTE.ST102.2002|publisher=[[SMPTE]] |isbn=978-1-61482-304-9}}</ref> Due to the size difference, CS perfed film cannot be run through a projector with standard KS sprocket teeth, but KS prints ''can'' be run on sprockets with CS teeth. Shrunken film with KS prints that would normally be damaged in a projector with KS sprockets may sometimes be run far more gently through a projector with CS sprockets because of the smaller size of the teeth. Magnetic striped 35&nbsp;mm film became obsolete in the 1980s after the advent of [[Dolby Stereo]], as a result film with CS perfs is no longer manufactured.

During continuous contact printing, the raw stock and the negative are placed next to one another around the sprocket wheel of the printer. The negative, which is the closer of the two to the sprocket wheel (thus creating a slightly shorter path), must have a marginally shorter pitch between perforations (0.1866&nbsp;in pitch); the raw stock has a long pitch (0.1870&nbsp;in). While cellulose nitrate and cellulose diacetate stocks used to shrink during processing slightly enough to have this difference naturally occur, modern safety stocks do not shrink at the same rate, and therefore negative (and some intermediate) stocks are perforated at a pitch of 0.2% shorter than print stock.<ref name="case" />

==Technical specifications==
[[File:35mmareas.svg|thumb|upright=2.04|Areas on an Academy-width 35&nbsp;mm spherical film print: {{ordered list |item_style=margin:0
    |1=Camera aperture
    |2=Academy ratio, 1.375:1
    |3=1.85:1 Ratio
    |4=1.6{{overline|6}}:1 Ratio
    |5=Television scanned area
    |6=Television "action safe" area
    |7=Television "title safe" area
}}]]

Technical specifications for 35&nbsp;mm film are standardized by [[Society of Motion Picture and Television Engineers|SMPTE]].

* 16 frames per foot ({{convert|0.748|in|mm}} per frame (long pitch))
* 24 frames per second (fps); {{convert|90|ft|m}} per minute. {{convert|1000|ft|m}} is about 11&nbsp;minutes at 24 fps.
* vertical pulldown
* 4 perforations per frame (all projection and most origination except 3-perf). 1 perforation = {{frac|3|16}}&nbsp;in or 0.1875&nbsp;in. 1 frame = {{frac|3|4}}&nbsp;in or 0.75&nbsp;in.

'''35&nbsp;mm spherical'''<ref name="asc" />

* ''Aspect ratio'': 1.375:1 on camera aperture; 1.85:1 and 1.6{{overline|6}}:1 are hard- or soft-matted over this
* ''Camera aperture'': {{convert|0.866|by|0.630|in|mm|abbr=on}}
* ''Projector aperture'' (full 1.375:1): {{convert|0.825|by|0.602|in|mm|abbr=on}}
* ''Projector aperture'' (1.6{{overline|6}}:1): {{convert|0.825|by|0.497|in|mm|abbr=on}}
* ''Projector aperture'' (1.85:1): {{convert|0.825|by|0.446|in|mm|abbr=on}}
* ''TV station aperture'': {{convert|0.816|by|0.612|in|mm|abbr=on}}
* ''TV transmission'': {{convert|0.792|by|0.594|in|mm|abbr=on}}
* ''TV safe action'': {{convert|0.713|by|0.535|in|mm|abbr=on}}; corner radii: {{convert|0.143|in|mm}}
* ''TV safe titles'': {{convert|0.630|by|0.475|in|mm|abbr=on}}; corner radii: {{convert|0.125|in|mm}}

'''Super 35&nbsp;mm film'''<ref name="asc" />

* ''Aspect ratio'': 1.3{{overline|3}}:1 on 4-perf camera aperture
* ''Camera aperture (4-perf)'': {{convert|0.980|by|0.735|in|mm|abbr=on}}
* ''Picture used'' (35&nbsp;mm anamorphic): {{convert|0.945|by|0.394|in|mm}}
* ''Picture used'' (70&nbsp;mm blowup): {{convert|0.945|by|0.430|in|mm}}
* ''Picture used'' (35&nbsp;mm flat 1.85): {{convert|0.945|by|0.511|in|mm}}

'''35&nbsp;mm anamorphic'''<ref name="asc" />

* ''Aspect ratio'': 2.39:1, in a 1.19:1 frame with a 2x horizontal anamorphosis
* ''Camera aperture'': {{convert|0.866|by|0.732|in|mm}}
* ''Projector aperture'': {{convert|0.825|by|0.690|in|mm}}

==See also==
{{portal|Film}}
* [[History of film|History of the art and technique of making films]]
* [[Original camera negative]]
* [[List of motion picture film formats]]
* [[List of motion picture film stocks]]

==Footnotes==
{{reflist|group=fn}}

==References==
{{reflist|30em}}

==External links==
* [http://www.widescreenmuseum.com/ American Widescreen Museum]
* [http://www.fujifilm.com/products/motion_picture/index.html Fujifilm Motion Picture Films]
* [https://web.archive.org/web/20060711032229/http://www.kodak.com/US/en/motion/ Kodak: Cinematography]
* [http://www.sprocketschool.org/wiki/List_of_analog_film_exhibitors List of venues and organizations] currently running [[motion picture film]]
* [https://southtree.com/pages/the-10-most-significant-35mm-films-ever-made A Brief History of The 10 Most Significant* 35mm Films Ever Made] at Southtree

{{Film formats}}

{{DEFAULTSORT:35mm Film}}
[[Category:Audiovisual introductions in 1889]]
[[Category:Film and video technology]]
[[Category:Film formats]]
[[Category:Motion picture film formats]]
[[Category:Thomas Edison]]