Editing 35 mm movie film (section)

==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>