Editing Video camera

{{Short description|Camera used for electronic motion picture acquisition}}
[[File:Sony Handycam DCR-SR35 20190810.jpg|thumb|A video camera manufactured by [[Sony]], part of [[Handycam]] line.]]

A '''video camera''' is an [[Optics|optical]] instrument that captures [[video]]s, as opposed to a [[movie camera]], which records images on [[Film stock|film]]. Video cameras were initially developed for the [[television]] industry but have since become widely used for a variety of other purposes.

Video cameras are used primarily in two modes. The first, characteristic of much early broadcasting, is [[live television]], where the camera feeds [[present|real time]] images directly to a screen for immediate observation.  A few cameras still serve live television production, but most live connections are for [[security camera|security]], military/tactical, and industrial operations where surreptitious or remote viewing is required. In the second mode the images are recorded to a storage device for archiving or further processing; for many years, [[videotape]] was the primary format used for this purpose, but was gradually supplanted by [[optical disc]], [[hard disk]], and then [[flash memory]]. Recorded video is used in television production, and more often [[surveillance]] and monitoring tasks in which unattended recording of a situation is required for later analysis.

==Types and uses==
Modern video cameras have numerous designs and use:
*[[Professional video camera]]s, such as those used in [[television production]], may be [[television studio]]-based or mobile in the case of an [[electronic field production]] (EFP). Such cameras generally offer extremely fine-grained manual control for the camera operator, often to the exclusion of automated operation. They usually use three sensors to separately record red, green and blue.
* [[Camcorder]]s combine a camera and a [[VCR]] or other recording device in one unit; these are mobile, and were widely used for television production, [[home movie]]s, [[electronic news gathering]] (ENG) (including [[citizen journalism]]), and similar applications. Since the transition to digital video cameras, most cameras have in-built recording media and as such are also camcorders. [[Action camera]]s often have 360° recording capabilities.
* [[Closed-circuit television]] (CCTV) generally uses [[pan–tilt–zoom camera]]s (PTZ), for security, surveillance, and/or monitoring purposes. Such cameras are designed to be small, easily hidden, and able to operate unattended; those used in industrial or scientific settings are often meant for use in environments that are normally inaccessible or uncomfortable for humans, and are therefore hardened for such hostile environments (e.g. [[Radiation hardening|radiation]], high heat, or toxic chemical exposure).
* [[Webcam]]s are video cameras that stream a live video feed to a computer.
* Many [[smartphones]] have built-in video cameras and even [[Camera phone|high-end smartphones]] can capture video in 4K resolution.
* Special camera systems are used for scientific research, e.g. on board a [[satellite]] or a [[space probe]], in [[artificial intelligence]] and [[robotics]] research, and in [[medical]] use. Such cameras are often tuned for non-visible radiation for [[infrared]] (for [[night vision]] and heat sensing) or [[X-ray]] (for medical and [[Speckle imaging|video astronomy]] use).

==History==
The earliest video cameras were based on the mechanical [[Nipkow disk]] and used in experimental broadcasts through the 1910s–1930s. All-electronic designs based on the [[video camera tube]], such as [[Vladimir Zworykin]]'s [[Iconoscope]] and [[Philo Farnsworth]]'s [[image dissector]], supplanted the Nipkow system by the 1930s. These remained in wide use until the 1980s, when cameras based on solid-state [[image sensors]] such as the [[charge-coupled device]] (CCD) and later [[CMOS]] [[active-pixel sensor]] (CMOS sensor) eliminated common problems with tube technologies such as [[Screen burn-in|image burn-in]] and streaking and made [[digital video]] [[workflow]] practical, since the output of the sensor is digital so it does not need conversion from analog.

The basis for [[solid-state electronics|solid-state]] image sensors is [[metal–oxide–semiconductor]] (MOS) technology,<ref name="Williams">{{cite book |last1=Williams |first1=J. B. |title=The Electronics Revolution: Inventing the Future |date=2017 |publisher=Springer |isbn=978-3-319-49088-5 |pages=245–8 |url=https://books.google.com/books?id=v4QlDwAAQBAJ&pg=PA245}}</ref> which originates from the invention of the [[MOSFET]] (MOS field-effect transistor) at [[Bell Labs]] in 1959.<ref name="computerhistory">{{cite journal|url=https://www.computerhistory.org/siliconengine/metal-oxide-semiconductor-mos-transistor-demonstrated/|title=1960: Metal Oxide Semiconductor (MOS) Transistor Demonstrated|journal=The Silicon Engine|publisher=[[Computer History Museum]] |access-date=August 31, 2019}}</ref> This led to the development of [[semiconductor]] image sensors, including the CCD and later the CMOS [[active-pixel sensor]].<ref name="Williams"/> The first semiconductor image sensor was the charge-coupled device, invented at Bell Labs in 1969,<ref>{{Cite book | title = Scientific charge-coupled devices | author = James R. Janesick | publisher = SPIE Press | year = 2001 | isbn = 978-0-8194-3698-6 | pages = 3–4 | url = https://books.google.com/books?id=3GyE4SWytn4C&pg=PA3 }}</ref> based on [[MOS capacitor]] technology.<ref name="Williams"/> The [[NMOS logic|NMOS]] active-pixel sensor was later invented at [[Olympus Corporation|Olympus]] in 1985,<ref>{{cite journal |last1=Matsumoto |first1=Kazuya |last2=Nakamura |first2=Tsutomu |last3=Yusa |first3=Atsushi |last4=Nagai |first4=Shohei |display-authors=1|date=1985 |title=A new MOS phototransistor operating in a non-destructive readout mode |journal=Japanese Journal of Applied Physics |volume=24 |issue=5A |page=L323|doi=10.1143/JJAP.24.L323 |bibcode=1985JaJAP..24L.323M |s2cid=108450116 }}</ref><ref name=fossum93>{{cite journal |last1=Fossum |first1=Eric R. |author1-link=Eric Fossum |title=Active pixel sensors: are CCDs dinosaurs? |journal=SPIE Proceedings Vol. 1900: Charge-Coupled Devices and Solid State Optical Sensors III |series=Charge-Coupled Devices and Solid State Optical Sensors III |volume=1900 |date=12 July 1993 |doi=10.1117/12.148585 |bibcode=1993SPIE.1900....2F |citeseerx=10.1.1.408.6558 |publisher=International Society for Optics and Photonics |pages=2–14 |s2cid=10556755 |editor1-last=Blouke |editor1-first=Morley M.}}</ref><ref>{{cite web |last1=Fossum |first1=Eric R. |author1-link=Eric Fossum |title=Active Pixel Sensors |website=[[Semantic Scholar]] |year=2007 |s2cid=18831792 |url=http://pdfs.semanticscholar.org/f510/d40cfe0556392bb2d34981f7158327dec169.pdf |archive-url=https://web.archive.org/web/20190309065505/http://pdfs.semanticscholar.org/f510/d40cfe0556392bb2d34981f7158327dec169.pdf |url-status=dead |archive-date=9 March 2019 |access-date=8 October 2019}}</ref> which led to the development of the CMOS active-pixel sensor at [[NASA]]'s [[Jet Propulsion Laboratory]] in 1993.<ref name="Fossum2014">{{cite journal |last1=Fossum |first1=Eric R. |author1-link=Eric Fossum |last2=Hondongwa |first2=D. B. |title=A Review of the Pinned Photodiode for CCD and CMOS Image Sensors |journal=IEEE Journal of the Electron Devices Society |date=2014 |volume=2 |issue=3 |pages=33–43 |doi=10.1109/JEDS.2014.2306412 |doi-access=free }}</ref><ref name=fossum93/>

Practical digital video cameras were also enabled by advances in [[video compression]], due to the impractically high [[computer memory|memory]] and [[bandwidth (computing)|bandwidth]] requirements of [[uncompressed video]].<ref name="Belmudez">{{cite book |last1=Belmudez |first1=Benjamin |title=Audiovisual Quality Assessment and Prediction for Videotelephony |date=2014 |publisher=Springer |isbn=978-3-319-14166-4 |pages=11–13 |url=https://books.google.com/books?id=ULTzBQAAQBAJ&pg=PA13}}</ref> The most important compression algorithm in this regard is the [[discrete cosine transform]] (DCT),<ref name="Belmudez"/><ref name="Huang">{{cite book |last1=Huang |first1=Hsiang-Cheh |last2=Fang |first2=Wai-Chi |title=Intelligent Multimedia Data Hiding: New Directions |date=2007 |publisher=Springer |isbn=978-3-540-71169-8 |page=41 |url=https://books.google.com/books?id=67W5BQAAQBAJ&pg=PA41}}</ref> a [[lossy compression]] technique that was first proposed in 1972.<ref name="Ahmed">{{cite journal |last=Ahmed |first=Nasir |author-link=N. Ahmed |title=How I Came Up With the Discrete Cosine Transform |journal=[[Digital Signal Processing (journal)|Digital Signal Processing]] |date=January 1991 |volume=1 |issue=1 |pages=4–5 |doi=10.1016/1051-2004(91)90086-Z |url=https://www.scribd.com/doc/52879771/DCT-History-How-I-Came-Up-with-the-Discrete-Cosine-Transform|url-access=subscription }}</ref> Practical digital video cameras were enabled by DCT-based video compression standards, including the [[H.26x]] and [[MPEG]] [[video coding standards]] introduced from 1988 onwards.<ref name="Huang"/>

The transition to [[digital television]] gave a boost to digital video cameras. By the early 21st century, most video cameras were [[digital cameras]].

With the advent of digital video capture, the distinction between professional video cameras and movie cameras has disappeared as the intermittent mechanism has become the same. Nowadays, mid-range cameras exclusively used for television and other work (except movies) are termed professional video cameras.

==Recording media==

Early video could not be directly recorded.<ref name=McLean /> The first somewhat successful attempt to directly record video was in 1927 with [[John Logie Baird]]’s disc based [[Phonovision]].<ref name=McLean /> The discs were unplayable with the technology of the time although later advances allowed the video to be recovered in the 1980s.<ref name=McLean>{{Cite web|url=http://www.tvdawn.com/tv1strx.htm|title='Phonovision': 1927-28 « the Dawn of TV}}</ref> The first experiments with using tape to record a video signal took place in 1951.<ref name=marsh /> The first commercially released system was Quadruplex videotape produced by [[Ampex]] in 1956.<ref name=marsh /> Two years later Ampex introduced a system capable of recording colour video.<ref name=marsh>{{cite web |url=https://blogs.library.duke.edu/bitstreams/2017/07/27/history-videotape-part-1/ |title=A History of Videotape, Part 1 |last=Marsh |first=Alex |date=27 July 2017 |website=Bitstreams |publisher=Duke University |access-date=11 February 2022 }}</ref> The first recording systems designed to be mobile (and thus usable outside the studio) were the [[Portapak]] systems starting with the Sony DV-2400 in 1967.<ref name=Buckingham /> This was followed in 1981 by the [[Betacam]] system where the tape recorder was built into the camera making a camcorder.<ref name=Buckingham>{{cite book |last1=Buckingham |first1=David |last2=Willett |first2=Rebekah |last3=Pini |first3=Maria|date=2011 |title=Home Truths?: Video Production and Domestic Life |url=https://books.google.com/books?id=KA13kssIGmEC&pg=PA9 |location= |publisher=University of Michigan Press |page=9 |isbn=978-0-472-05137-3}}</ref>

==Lens mounts==
[[File:Sony E mount.jpg|thumb|A lense with a Sony E mount]]
While some video cameras have built in lenses, others use interchangeable lenses connected via a range of mounts. Some like [[PV mount|Panavision PV]] and [[Arri PL]] are designed for movie cameras while others like [[Canon EF]] and [[Sony E-mount|Sony E]] come from still photography.<ref name=rhodes>{{cite news |last=Rhodes |first=Phil  |date=4 February 2018 |title=The RedShark Guide to Lens Mounts |url=https://www.redsharknews.com/production/item/4689-the-redshark-guide-to-lens-mounts |work=RedShark |access-date=3 March 2022}}</ref> A further set of mounts like [[S-mount (CCTV lens)|S-mount]] exist for applications like CCTV.

== See also ==
* [[Digital movie camera]]
* [[Digital single-lens reflex camera]]
* [[FireWire camera]]
* [[Professional video camera]]
* [[Recording at the edge]]
* [[Television production]]
* [[Three-CCD]]
* [[Video camera tube]]
* [[Videographer|Videograph]]
* [[Videotelephony]]
* [[Webcam]]
* [[Smart camera]]

== References ==
{{Reflist}}

==External links==
*{{Commons category-inline|Video cameras}}
*{{Wiktionary inline}}

{{Authority control}}

[[Category:Cameras by type]]
[[Category:Recording]]
[[Category:Optical devices]]