Editing Push processing

{{Short description|Film developing technique}}
{{Use mdy dates|date=December 2020}}
{{More citations needed|date=June 2009}}
[[File:Massage.jpg|thumb|upright|A photograph pushed by 2 stops, showing strong grain]]

'''Push processing''' in [[photography]], sometimes called '''uprating''', refers to a [[Photographic processing|film developing]] technique that increases the effective [[film speed|sensitivity]] of the film being processed.<ref name="Langford">{{cite book
|title = Basic Photography
|author = Michael Langford
|year = 2000
|edition = 7th
|publisher = Focal Press
|location = Oxford
|isbn = 0-240-51592-7
|url-access = registration
|url = https://archive.org/details/basicphotography00lang
}}</ref>{{page needed|date=December 2020}} Push processing involves developing the film for more time, possibly in combination with a higher temperature, than the manufacturer's recommendations. This technique results in effective overdevelopment of the film, compensating for [[underexposure]] in the camera. 

==Visual characteristics==
Push processing allows relatively insensitive films to be used under lighting conditions that would ordinarily be too low for adequate exposure at the required [[shutter speed]] and [[aperture]] combination. This technique alters the visual characteristics of the film, such as higher contrast, increased [[film grain|grain]] and lower resolution.<ref name="Langford" />{{page needed|date=December 2020}} Saturated and distorted colours are often visible on [[color film|colour film]] that has been push processed. 

''Pull processing'' involves overexposure and underdevelopment, effectively decreasing the sensitivity of the processed film. It is achieved by developing the film for a shorter time, and possibly at a lower temperature. Film that has been pull processed will display the opposite change in visual characteristics. This may be deliberately exploited for artistic effect.

==Exposure index==
[[File:Cinestill 800Tungsten Xpro C-41 135 film cartridge (01).jpg|thumb|A roll of [[Cinestill]] 135 color film showing checkboxes that can be used to remember the EI for push-processing (expressed in [[Exposure value|stops]] relative to the box speed of ISO 800/30°).]]

When a film's effective sensitivity has been varied, the resulting sensitivity is called the [[exposure index]]; the [[film speed|film's speed]] remains at the manufacturer's indication. For example, an [[Film speed|ISO]] 200/24° film could be push processed to EI 400/27° or pull processed to EI 100/21°.

==In cinema==
[[Andy Warhol]]'s 1965 8-hour art film ''[[Empire (1965 film)|Empire]]'', was shot on  ASA 400 [[Kodak Tri-X|Tri-X]] [[16mm film]] stock, which was then push processed to ASA 1000 to compensate for the dark conditions of filming the [[Empire State Building]] during the night.<ref>{{cite web | url=https://books.google.com/books?id=r6RIAQAAIAAJ | title=The Films of Andy Warhol, Part II: Exhibition Whitney Museum of American Art, March 30-April 24, 1994 | last1=Angell | first1=Callie | date=1994 }}</ref>

[[John Alcott]] won an Oscar "for his gorgeous use of natural lighting" in [[Stanley Kubrick]]'s 1975 period film ''[[Barry Lyndon]]'', set in the 18th century, where he succeeded in filming scenes lit only by candlelight through the use of special wide-aperture [[Carl Zeiss Planar 50mm f/0.7]] lenses designed for the low-light shooting on NASA's moon landings, and then push-processing the film stock.<ref>{{cite web|url=https://www.deepfocusreview.com/reviews/barrylyndon.asp|work=Deep Focus Review|last=Eggert|first=Brian|title=Barry Lyndon|date=January 9, 2013 |access-date=December 23, 2020|archive-date=March 28, 2022|archive-url=https://web.archive.org/web/20220328123527/https://deepfocusreview.com/definitives/barry-lyndon/}}</ref>

[[Larry Smith (cinematographer)|Larry Smith]], the cinematographer for Kubrick's 1999 film ''[[Eyes Wide Shut]]'', used push-processing to increase the intensity of the color.<ref name="asc">{{cite journal|url=http://www.theasc.com/magazine/oct99/sword/pg1.htm|title=A Sword in the Bed|first=Stephen|last=Pizzella|journal=[[American Cinematographer]]|issue=33|date=October 28, 1999|access-date=November 18, 2012|archive-date=June 21, 2013|archive-url=https://web.archive.org/web/20130621112726/http://www.theasc.com/magazine/oct99/sword/pg1.htm|url-status=live}}</ref>

[[Paul Thomas Anderson]] and Michael Bauman used this technique on their [[35mm movie film|35mm film]] stock for the 2017 film ''[[Phantom Thread]]'', also filling its frames with "theatrical haze" to "dirty up" the look of the film.<ref>{{cite web|last=O'Falt|first=Chris|date=December 20, 2017|title=How Paul Thomas Anderson Dirtied-Up 'Phantom Thread' to Avoid the Polish of 'The Crown'|url=https://www.indiewire.com/2017/12/phantom-thread-paul-thomas-anderson-cinematography-1201909965/|access-date=December 23, 2020|website=[[IndieWire]]}}</ref>

==See also==
* [[Film speed]]
* [[Latent image]]
* [[Photographic processing]]

==References==
{{Reflist}}

==External links==
{{Commons category}}
* [https://www.kodak.com/en/motion/page/push-pull-processing Push/Pull Processing] at [[Kodak]]

{{Photography}}

[[Category:Photographic techniques]]