{{Short description|Wide high-resolution film gauge}} thumb|upright=1.3|A 70 mm film strip with a human hand for scale

'''70&nbsp;mm film''' (or '''65&nbsp;mm film''') is a wide high-resolution film gauge for motion picture photography, with a negative area nearly 3.5 times as large as the standard 35&nbsp;mm motion picture film format.<ref name="Celestino2014">{{cite web |title='Inherent Vice' Will Screen in 70 mm in Select Theaters. But is Bigger Always Better? |url=https://www.indiewire.com/2014/12/inherent-vice-will-screen-in-70mm-in-select-theaters-but-is-bigger-always-better-67270/ |website=IndieWire |access-date=8 February 2019}}</ref> As used in cameras, the film is {{convert|65|mm|in|abbr=on}} wide. For projection, the original 65&nbsp;mm film is printed on {{convert|70|mm|in|abbr=on}} film. The additional 5&nbsp;mm contains the four magnetic stripes, holding six tracks of stereophonic sound. Although later 70&nbsp;mm prints use digital sound encoding (specifically the DTS format), the vast majority of existing and surviving 70&nbsp;mm prints pre-date this technology.

Each frame is five perforations tall (i.e., 23.8125&nbsp;mm or 15/16 inches tall), with an image aspect ratio of 2.2:1.<ref>{{Cite web|url=https://www.widescreen.org/aspect_ratios.shtml|title=Widescreen.org|last=John|website=widescreen.org|access-date=2018-10-12}}</ref> The use of anamorphic Ultra Panavision 70 lenses squeezes an ultra-wide 2.76:1 aspect ratio horizontally into that 2.2:1 imaging area. To this day, Ultra Panavision 70 produces the second widest picture size; surpassed only by Polyvision, which was only used for 1927's ''Napoléon''.

With regard to exhibition, 70&nbsp;mm film was always considered a specialty format reserved for epics and spectacle films shot on 65&nbsp;mm and blockbuster films that were released both in 35&nbsp;mm and as 70&nbsp;mm blow-ups. While few venues were equipped to screen this special format, at the height of its popularity most major markets and cities had a theater that could screen it.<ref name="thegate.ca">{{cite web |title=TIFF showcases the rarity and resurgence of 70 mm film |url=https://www.thegate.ca/film/031559/tiff-showcases-rarity-resurgence-70mm-film/ |website=The Gate |access-date=8 February 2019}}</ref> Some venues continue to screen 70&nbsp;mm to this day or have even had 70&nbsp;mm projectors permanently or temporarily installed for more recent 70&nbsp;mm releases.<ref name="DunkirkRelease2017">{{cite web |title=Warner Bros. Prepping 'Dunkirk' for One of the Largest 70 mm Releases of Last 25 Years |url=https://www.hollywoodreporter.com/behind-screen/warner-bros-prepping-dunkirk-one-largest-70mm-releases-last-25-years-1018698 |website=Hollywood Reporter |access-date=8 February 2019}}</ref>

== History == thumb|Faded vintage 70&nbsp;mm positive film with four magnetic strips containing six-channel stereophonic sound Films formatted with a width of 70&nbsp;mm have existed since the early days of the motion picture industry. The first 70&nbsp;mm format film was most likely footage of the Henley Regatta, which was projected in 1896 and 1897, but may have been filmed as early as 1894. It required a specially built projector built by Herman Casler in Canastota, New York and had a ratio similar to full frame, with an aperture of {{convert|2.75|in|mm}} by {{convert|2|in|mm}}. There were also several film formats of various sizes from 50 to 68&nbsp;mm which were developed from 1884 onwards, including Cinéorama (not to be confused with the entirely distinct "Cinerama" format), started in 1900 by Raoul Grimoin-Sanson. In 1914 the Italian Filoteo Alberini invented a panoramic film system utilising a 70&nbsp;mm wide film called Panoramica.<ref>"Preserving Wide Film History" Grant Lobban, Journal of the BKSTS Vol 67 No.4 April 1985</ref>

===Fox Grandeur=== {{main|70&nbsp;mm Grandeur film}} In 1928, William Fox of the Fox Film Corporation, in personal collaboration with Theodore Case as the Fox-Case Corporation, began working on a wide film format using 70&nbsp;mm film which they named Grandeur. Cameras were ordered by Fox-Case from Mitchell Camera Corp, with the first 70&nbsp;mm production cameras, designated as the Mitchell Model FC camera, delivered to Fox-Case in May 1929. This was one of a number of wide-film processes developed by some of the major film studios at about that time. However, due to the financial strains of the Great Depression, along with strong resistance from movie theater owners, who were in the process of equipping their theaters for sound, none of these systems became commercially successful. Fox dropped Grandeur in 1930.<ref>"Preserving Wide Film History" Grant Lobban, ''Journal of the BKSTS'' Vol 67 No.4 (April 1985)</ref>

===Todd-AO=== thumb|right|upright=1.42|Todd-AO / Panavision (5-perf) 65 mm negative frame dimensions; the ''Ultra Panavision'' 1.25× anamorphic process is represented by the distorted circle. {{main|Todd-AO process}} Producer Mike Todd had been one of the founders of Cinerama, a wide-screen movie process that was launched in 1952. Cinerama employed three 35&nbsp;mm film projectors running in synchronism to project a wide (2.6:1) image onto a deeply curved screen. Although the results were impressive, the system was expensive, cumbersome and had some serious shortcomings due to the need to match up three separate projected images. Todd left the company to develop a system of his own which, he hoped, would be as impressive as Cinerama, yet be simpler and cheaper and avoid the problems associated with three-strip projection; in his own words, he wanted "Cinerama out of one hole".

In collaboration with the American Optical Company, Todd developed a system which was to be called "Todd-AO". This uses a single 70&nbsp;mm wide film and was introduced with the film ''Oklahoma!'' in October 1955. The 70&nbsp;mm film is perforated at the same pitch (0.187 inch, 4.75&nbsp;mm) as standard 35&nbsp;mm film. With a five-perforation pull-down, the Todd-AO system provides a frame dimension of 1.912 inch (48.56&nbsp;mm) by 0.87 inch (22.09&nbsp;mm) giving an aspect ratio of 2.2:1.

The original version of Todd-AO used a frame rate of 30 per second, 25% faster than the 24 frames per second that was (and is) the standard; this was changed after the second film – ''Around the World in 80 Days'' - because of the need to produce (24 frame/sec) 35&nbsp;mm reduction prints from the Todd-AO 65&nbsp;mm negative. The Todd-AO format was originally intended to use a deeply curved Cinerama-type screen but this failed to survive beyond the first few films.<ref>"In the Splendour of 70&nbsp;mm Part 1" Grant Lobban, Journal of the BKSTS Vol68 No.12 December 1986</ref> However, in the 1960s and 70s, such films as ''The Sound of Music'' and ''Patton'' (which had been filmed in a process known as Dimension 150) were shown in some Cinerama theaters, which allowed for deeply curved screens.<ref>{{cite web|url=http://cinematreasures.org/theaters/4784|title=Atlanta Theatre|work=Cinema Treasures|access-date=1 December 2015}}</ref>

Todd-AO adopted a similar multi-channel magnetic sound system to the one developed for Cinemascope two years earlier, recorded on "stripes" of magnetic oxide deposited on the film. However, Todd-AO has six channels instead of the four of Cinemascope and due to the wider surround stripe and faster film speed provides superior audio quality. Five of these six channels are fed to five speakers spaced behind the screen, and the sixth is fed to surround speakers around the walls of the auditorium.

===Panavision and the 65/70 mm format=== {{main|Super Panavision 70|Ultra Panavision 70}} Panavision developed their own 65/70&nbsp;mm system that was technically compatible and virtually identical to Todd-AO. Monikered as Super Panavision 70, it used spherical lenses and the same 2.2:1 aspect ratio at 24 frames per second. Panavision also had another 65&nbsp;mm system, Ultra Panavision 70, which sprang from the MGM Camera 65 system they helped develop for MGM that was used to film ''Raintree County'' and ''Ben-Hur''. Both Ultra Panavision 70 and MGM Camera 65 employed an anamorphic lens with a 1.25× squeeze on a 65&nbsp;mm negative (as opposed to 35&nbsp;mm CinemaScope which used a 2× compression, or 8-perf, horizontally filmed 35&nbsp;mm Technirama which used a 1.5× compression). When projected on a 70&nbsp;mm print, a 1.25× anamorphic projection lens was used to decompress the image to an aspect ratio of 2.76:1, one of the widest ever used in commercial cinema.

==Decline and resurgence== Due to the high cost of 70&nbsp;mm film and the expensive projection system and screen required to use the stock, distribution for films using the stock was limited, although this did not always hurt profits. Most 70&nbsp;mm films were also released on 35&nbsp;mm film for a wider distribution after the initial debut of the film. ''South Pacific'' (1958), ''Lawrence of Arabia'' (1962), ''My Fair Lady'' (1964), and ''The Sound of Music'' (1965) are well-known films widely shown in 70&nbsp;mm format with a general release in 35&nbsp;mm format. 70&nbsp;mm film received a brief resurgence in the 1980s when it became popular to make "blow-up" prints of 35&nbsp;mm titles. It had another resurgence in the mid-2010s with the release of ''The Master'' (2012), ''The Hateful Eight'' (2015) and ''Dunkirk'' (2017), with a small number of venues getting temporary or permanent 70&nbsp;mm film projectors in order to be able to screen these titles.<ref name="DunkirkRelease2017" /> Quentin Tarantino, in particular, led a successful campaign to have the equipment required to show ''The Hateful Eight'' in Ultra Panavision installed in 100 cinemas worldwide.<ref>{{Cite web|url=https://www.bfi.org.uk/lists/10-great-films-shot-70mm|title=10 Great Films Shot in 70 mm|last=Thrift|first=Matthew|date=22 January 2018|website=BFI (British Film Institute)|access-date=24 December 2019}}</ref>

===Blow-ups=== The 35&nbsp;mm to 70&nbsp;mm "blow-up" process produces 70&nbsp;mm release prints from 35&nbsp;mm negatives, so that films shot on the smaller format could benefit from 70&nbsp;mm image and sound quality. This process began in the 1960s with titles like ''The Cardinal'' (1963)<ref>{{cite web |title=The Beginning of the End |url=http://www.widescreenmuseum.com/widescreen/35-70mm.htm |website=in70mm |access-date=8 February 2019}}</ref> and continues up until the present day, with the height of its popularity being in the 1980s. These enlargements often provided richer colors, and a brighter, steadier and sharper (though often grainier) image, but the main benefit was the ability to provide 6-channel stereophonic sound as most theaters before the mid-70s (before the advent of Dolby A) were screening 35&nbsp;mm prints with single channel monaural sound.<ref name="Celestino2014" /> However these "blow-ups" rarely used the full six channels of the Todd-AO system and instead used the four-track mixes made for 35&nbsp;mm prints, the additional half-left and half-right speakers of the Todd-AO layout being fed with a simple mix of the signals intended for the adjacent speakers (known as a "spread") or simply left blank.<ref name="ReferenceA">"Mixing Dolby Stereo Film Sound" Larry Blake Recording Engineer/Producer Vol12 No.1 Feb 1981</ref> If a 70&nbsp;mm film was shown in a Cinerama theatre, the Cinerama sound system was used. From 1976 onwards, many 70&nbsp;mm prints used Dolby noise reduction on the magnetic tracks but Dolby disliked of the "spread" and instead re-allocated the 6 available tracks to provide for left, center and right screen channels, left and right surround channels plus a "low-frequency enhancement" channel to give more body to low-frequency bass.<ref>The CP200 – A Comprehensive Cinema Theater Audio Processor David Robinson Journal of the SMPTE Sept 1981</ref> This layout came to be known as "5.1" (the "point one" is the low-frequency enhancement channel) and was subsequently adopted for digital sound systems used with 35&nbsp;mm.

In the 1980s the use of these "blow-ups" increased with large numbers of 70&nbsp;mm prints being made of some blockbusters of the period such as the 125 70&nbsp;mm prints made of ''The Empire Strikes Back'' (1980).<ref name="ReferenceA"/> However the early 1990s saw the advent of digital sound systems (Dolby Digital, DTS and SDDS) for 35&nbsp;mm prints which meant that 35&nbsp;mm could finally match 70&nbsp;mm for sound quality but at a far lower cost. Coupled with the rise of the multiplex cinema, which meant that audiences were increasingly seeing films on relatively small screens rather than the giant screens of the old "Picture Palaces", this meant that the expensive 70&nbsp;mm format went out of favour again. The DTS digital sound-on-disc system was adapted for use with 70&nbsp;mm film, thus saving the significant costs of magnetic striping, but this has not been enough to stop the decline, and 70&nbsp;mm prints were rarely made.

Among some of the more recent 70&nbsp;mm blow-up titles are Paul Thomas Anderson's ''Inherent Vice'' (2014),<ref name="Celestino2014" /> ''Phantom Thread'' (2017) and ''Licorice Pizza'' (2021), Patty Jenkins's ''Wonder Woman'' (2017),<ref>{{cite web |title=70 mm Blow Ups 2017 |url=https://www.in70mm.com/library/blow_up/year/2017/index.htm |website=in70mm |access-date=8 February 2019 |archive-date=9 February 2019 |archive-url=https://web.archive.org/web/20190209180121/https://www.in70mm.com/library/blow_up/year/2017/index.htm |url-status=dead }}</ref> Steven Spielberg's ''Ready Player One'' (2018)<ref>{{cite web |title='Ready Player One' in 70 mm Film Opens on 22 Screens |url=https://www.hollywoodreporter.com/behind-screen/ready-player-one-70mm-film-opens-22-screens-1098364 |website=Hollywood Reporter |access-date=8 February 2019}}</ref> and Brady Corbet's ''The Brutalist'' (2024).

=== Current use === From 1970, the usage of 65&nbsp;mm negative film drastically reduced, although the Soviet Union (who used 70&nbsp;mm stock) continued to use it frequently until the end of the 1980s. This was in part due to the high cost of 65&nbsp;mm raw stock and processing. Some of the few films since 1990 shot entirely on 65&nbsp;mm stock are Kenneth Branagh's ''Hamlet'' (1996), Ron Fricke's ''Baraka'' (1992) and its sequel, ''Samsara'' (2011) and Quentin Tarantino's ''The Hateful Eight'' (2015). Some titles used a mixture of 5-perf and 15-perf (IMAX) 65&nbsp;mm stock, including Christopher Nolan's films ''Dunkirk'' (2017), ''Tenet'' (2020) and ''Oppenheimer'' (2023), and Ryan Coogler's ''Sinners'' (2025).

Other titles with a significant amount of 65&nbsp;mm footage (both 5-perf and 15-perf) include Ron Howard's ''Far and Away'' (1992), Kenneth Branagh's ''Murder on the Orient Express'' (2017) and ''Death on the Nile'' (2022), Paul Thomas Anderson's ''The Master'' (2012), and Christopher Nolan's ''The Dark Knight'' (2008), ''Inception'' (2010),<ref>{{cite news|url=https://collider.com/director-christopher-nolan-and-producer-emma-thomas-interview-inception-they-talk-3d-what-kind-of-cameras-they-used-pre-viz-wb-and-a-lot-more/ |title=Christopher Nolan and Emma Thomas Interview Inception – They Talk 3D, What Kind of Cameras They Used, Pre-Viz, WB, and a Lot More! |work=Collider |first=Steve 'Frosty' |last=Weintraub |date=25 March 2010 |access-date=1 December 2015 |url-status=live |archive-url=https://web.archive.org/web/20100327204348/http://www.collider.com/2010/03/25/director-christopher-nolan-and-producer-emma-thomas-interview-inception-they-talk-3d-what-kind-of-cameras-they-used-pre-viz-wb-and-a-lot-more/ |archive-date=27 March 2010 }}</ref> ''The Dark Knight Rises'' (2012) and ''Interstellar'' (2014).

Since the 2010s, most movie theaters have converted to digital projection systems, resulting in the removal of both 35&nbsp;mm (the previous industry standard) projectors and 70&nbsp;mm projectors.<ref>{{cite news|url=https://variety.com/2013/film/news/digital-cinema-conversion-nears-end-game-1200500975/|title=Digital Cinema Conversion Nears End Game|work=Variety|first=Leo|last=Barraclough|date=23 June 2013|access-date=1 December 2015}}</ref> However some venues and organizations remain committed to screening 70&nbsp;mm film, seeing the special format as something that can set them apart and be an audience draw in an industry where most movies are screened digitally.<ref>{{cite web |title=The Film Stays in the Picture: A Guide to 70 mm Film Projection |url=https://consequenceofsound.net/2018/09/a-guide-to-70mm-projection/ |website=Consequence of Sound |access-date=8 February 2019}}</ref>

70&nbsp;mm film festivals continue to take place regularly at venues such as The Somerville Theatre in Somerville, Massachusetts,<ref>{{Cite web|url=http://scoutsomerville.com/somerville-theatre-70mm-film-festival/|archive-url=https://web.archive.org/web/20160923223034/http://scoutsomerville.com/somerville-theatre-70mm-film-festival/|url-status=usurped|archive-date=September 23, 2016|title=70 mm Film Festival Celebrates Cinematic Classics {{!}} Scout Somerville|last=Feedore|first=Elliott|website=scoutsomerville.com|language=en-US|access-date=2017-05-19}}</ref> The Music Box Theatre in Chicago,<ref>{{Cite web|url=http://www.rogerebert.com/balder-and-dash/70mm-film-festival-the-ultimate-edition-arrives-at-chicagos-music-box-theater|title="70 mm Film Festival: The Ultimate Edition" Arrives at Chicago's Music Box Theater {{!}} Balder and Dash {{!}} Roger Ebert|last=Sobczynski|first=Peter|website=rogerebert.com|language=en|access-date=2017-05-19}}</ref> the Hollywood Theatre in Portland, Oregon,<ref>{{cite web |title=Hollywood Signature Film Series: 70mm |url=https://hollywoodtheatre.org/programs/series/70mm/t |website=Hollywood Theatre}}</ref> the American Cinematheque's Aero and Egyptian Theaters in Los Angeles,<ref>{{cite web |title=The Return of 70 mm |url=http://americancinematheque.blogspot.com/2017/08/the-return-of-70mm-by-wade-major.html |website=American Cinematheque Blog |access-date=8 February 2019}}</ref> the Museum of the Moving Image in New York City,<ref>{{cite web |title=See it Big! 70 mm |url=http://www.movingimage.us/programs/2017/07/19/detail/see-it-big-70mm/ |website=Museum of the Moving Image - Programs |access-date=8 February 2019}}</ref> the TIFF Bell Lightbox in Toronto,<ref name="thegate.ca"/> the Worcester Polytechnic Institute in Worcester, Massachusetts,<ref>{{Cite web|url=https://lnl.wpi.edu/services/projection.html|title=Lens and Lights &#124; Projection|access-date=3 November 2020}}</ref> and the AFI Silver Theatre<ref>{{Cite web |title=AFI Silver Theatre and Cultural Center |url=https://vista.afi.com/Browsing/Cinemas/Details/1001 }}</ref> in Silver Spring, Maryland, among others.

== Uses of 70&nbsp;mm == {{more citations needed|section|date=April 2026}} ===Ultra Panavision=== {{main|Ultra Panavision 70}} <!-- Image with inadequate rationale removed: [[Image:Ben-Hur chariot race.jpg|thumb|380px|The chariot race scene from ''Ben-Hur'', illustrating the extremely wide aspect ratio used.]] --> An anamorphic squeeze combined with 65&nbsp;mm film allowed for extremely wide aspect ratios to be used while still preserving quality. This was used in the 1957 film ''Raintree County'' and to incredible success in the 1959 film ''Ben-Hur'' and the 2015 film ''The Hateful Eight'', both of which were filmed with the Ultra Panavision 70/MGM Camera 65 process at an aspect ratio of 2.76:1. It required the use of a 1.25× anamorphic lens to compress the image horizontally, and a corresponding lens on the projector to uncompress it.

===Visual effects=== Limited use of 65&nbsp;mm film was revived in the late 1970s for some of the visual effects sequences in films like ''Close Encounters of the Third Kind'', mainly because the larger negative did a better job than 35&nbsp;mm negative of minimizing visible film grain during optical compositing. 65&nbsp;mm was the primary film format used at VFX pioneer Douglas Trumbull's facility EEG (Entertainment Effects Group), which later became Boss Film Studios, run by ex-Industrial Light & Magic (ILM) supervisor Richard Edlund. Since the 1990s, a handful of films (such as ''Spider-Man 2'') have used 65mm for this purpose, but the usage of digital intermediate for compositing has largely negated these issues. Digital intermediate offers other benefits such as lower cost and a greater range of available lenses and accessories to ensure a consistent look to the footage.

===IMAX=== thumb|right|upright=1.64|IMAX (15-perf) horizontal pulldown 70 mm film and frame dimensions {{main|IMAX}} A horizontal variant of 70&nbsp;mm, with an even bigger picture area, is used for the high-performance IMAX format which uses a frame that is 15 perforations wide on 70&nbsp;mm film. The Dynavision and Astrovision systems each use slightly less film per frame and vertical pulldown to save print costs while being able to project onto an IMAX screen. Both were rare, with Astrovision largely used in Japanese planetariums. IMAX introduced a digital projection system in the late 2000s and most IMAX venues have migrated to a digital setup.<ref>{{cite news|url=http://www.studiodaily.com/2013/10/film-loses-more-ground-as-imax-switches-flagship-theaters-to-digital/|title=Film Loses More Ground As Imax Switches Flagship Theaters to Digital|work=Studio Daily|first=Bryant|last=Frazer|date=24 October 2013|access-date=1 December 2015}}</ref>

===70&nbsp;mm 3D early use=== The first commercial introduction of 70&nbsp;mm single projector 3D was the 1967 release of ''Con la muerte a la espalda'', a Spanish/French/Italian co-production which used a process called Hi-Fi Stereo 70, itself based on a simplified, earlier developed Soviet process called Stereo-70. This process captured two anamorphic images, one for each eye, side by side on 65&nbsp;mm film. A special lens on a 70&nbsp;mm projector added polarization and merged the two images on the screen. The 1971 re-release of Warner Bros.' ''House of Wax'' used the side-by-side StereoVision format and was distributed in both anamorphically squeezed 35&nbsp;mm and deluxe non-anamorphic 70&nbsp;mm form. The system was developed by Allan Silliphant and Chris Condon of StereoVision International Inc., which handled all technical and marketing aspects on a five-year special-royalty basis with Warner Bros. The big screen 3D image was both bright and clear, with all the former sync and brightness problems of traditional dual 35&nbsp;mm 3D eliminated. Still, it took many years more before IMAX began to test the water for big-screen 3D, and sold the concept to Hollywood executives.

===IMAX 3D=== Hollywood has released films shot on 35&nbsp;mm as IMAX blow-up versions. Many 3D films were shown in the 70&nbsp;mm IMAX format. ''The Polar Express'' in IMAX 3D 70&nbsp;mm earned 14 times as much, per screen, as the simultaneous 2D 35&nbsp;mm release of that film in the fall of 2004.

==Technical specifications==

===Standard 65&nbsp;mm (5/70) (Todd-AO, Super Panavision)=== * spherical lenses * 5 perforations/frame (1 perforation = 0.1875 in or 3/16 in, thus 1 frame of 70&nbsp;mm film has a height of 0.9375 in or 15/16 in)<!-- How much of that height is the active image area? Is there some gap between the top of one image and the bottom of another? --> * 42 frames/meter (12.8 frames/ft) * 34.29&nbsp;meters/minute (112.5&nbsp;ft/minute) * vertical pulldown * 24 frames/second * ''camera aperture'': 52.63 by 23.01&nbsp;mm (2.072 by 0.906&nbsp;in)<ref name="awsm_dimensions">{{cite web|url=http://www.widescreenmuseum.com/widescreen/filmdims.htm|work=The American WideScreen Museum|title=Film Frame Dimensions|access-date=1 December 2015}}</ref> * ''projection aperture'': 48.56 by 22.10&nbsp;mm (1.912 by 0.870&nbsp;in)<ref name="awsm_dimensions" /> * 305&nbsp;m (1000&nbsp;feet), about 9 minutes at 24 frame/s = 4.5&nbsp;kg (10 pounds) in can * ''aspect ratio'': 2.2:1

===Ultra Panavision 70 (MGM Camera 65)=== {{main|Ultra Panavision 70}} ''Same as Standard 65 mm except'' * ''projection aperture'': 48.59 by 22.05&nbsp;mm (1.913 by 0.868&nbsp;in)<ref name="awsm_dimensions" /> * MGM Camera 65 lenses built by Panavision employed a square-shaped, double wedge-prism anamorphic attachment in front of a spherical objective lens. By the time of ''Mutiny on the Bounty (1962)'' Panavision had developed a new set of Ultra Panavision 70 lenses that used a high quality cylindrical anamorphic element in front of the objective lens. These new lenses were far superior to the prism anamorphics—they were lighter, transmitted more light and suffered from less spherical and chromatic aberration. * 1.25x squeeze factor, projected aspect ratio 2.76:1

===Showscan=== {{main|Showscan}} ''Same as Standard 65&nbsp;mm except'' * 60 frames per second * 180 degree shutter

===IMAX (15/70)=== * spherical lenses * 70&nbsp;mm film, 15 perforations per frame * horizontal rolling loop movement, from right to left (viewed from emulsion side) * 24 frames per second * ''camera aperture:'' {{convert|70.41|x|52.63|mm|in|abbr=on}} * ''projection aperture:'' at least {{convert|2|mm|in|abbr=on}} less than camera aperture on the vertical axis and at least {{convert|0.41|mm|in|abbr=on}} less on the horizontal axis * ''aspect ratio:'' 1.43:1

===IMAX Dome / OMNIMAX=== ''Same as IMAX except'' * fisheye lens * lens optically centered {{convert|9.4|mm|in|abbr=on}} above film horizontal center line * projected elliptically on a dome screen, 20° below and 110° above perfectly centered viewers

===Omnivision Cinema 180=== ''same as standard 65/70 except:'' * photographed and projected with special fisheye lenses matched to large 180-degree dome screen * Theatres upgraded from 70&nbsp;mm 6-track analog sound to DTS digital sound in 1995.

Omnivision started in Sarasota, Florida. Theatres were designed to compete with Omnimax but with much lower startup and operating costs. Most theatres were built in fabric domed structures designed by Seaman Corporation. The last known OmniVision theatres to exist in USA are The Alaska Experience Theatre in Anchorage, Alaska, built in 1981 (closed in 2007, reopened in 2008), and the Hawaii Experience Theatre in Lahaina, Hawaii (closed in 2004). Rainbow's End (theme park) in NZ had the only remaining permanent Cinema 180 attraction until May 2015 when it was demolished. One of the few producers of 70&nbsp;mm films for Cinema 180 was the German company Cinevision (today AKPservices GmbH, Paderborn).

===Dynavision (8/70)=== thumb|right|upright=1.42|8-perf 70&nbsp;mm film diagram * fisheye or spherical lenses, depending on if projecting for a dome or not * vertical pulldown * 24 or 30 frames per second * ''camera aperture'': 52.83 by 37.59&nbsp;mm (2.080 by 1.480&nbsp;in)

===Astrovision (10/70)=== * vertical pulldown * normally printed from an Omnimax negative * projected onto a dome * almost exclusively in use only by Japanese planetariums * the only 70&nbsp;mm format without sound, hence the only one with perforations next to the edges

==See also== * 70&nbsp;mm Grandeur film * Cine 160 * Cinerama * Dolby Stereo 70&nbsp;mm Six Track * IMAX * Super Panavision 70 * Super Technirama 70 * Todd-AO * Ultra Panavision 70 * List of film formats * List of early wide-gauge films * List of 70&nbsp;mm films

==References== {{Reflist|30em}}

== External links == * [http://www.widescreenmuseum.com/ The American WideScreen Museum] * [http://www.in70mm.com/ in70mm.com — The 70&nbsp;mm Newsletter], devoted to 70&nbsp;mm films new and old * [http://www.in70mm.com/dp70/ The History of the Todd-AO Projector] * [http://www.sprocketschool.org/wiki/List_of_70mm_film_exhibitors Current List of 70&nbsp;mm Film Exhibitors]

{{Film formats}} {{authority control}}

Category:70 mm film Category:Motion picture film formats