View source for Digital single-lens reflex camera

{{short description|Single-lens reflex camera with a digital image sensor and recording mechanism}}
[[File:SLR cross section.svg|thumb|upright=1.2|The photographer can see the subject in the mirror before taking an image. When taking an image the mirror will swing up and light will go to the sensor instead.
{{ordered list
| [[Camera lens]]
| Reflex mirror
| [[Focal-plane shutter]]
| [[Image sensor]]
| Matte focusing screen
| Condenser lens
| [[Pentaprism]]/[[pentamirror]]
| [[Viewfinder]] eyepiece
}}]]

A '''digital single-lens reflex camera''' ('''digital SLR''' or '''DSLR''') is a [[digital camera]] that combines the optics and mechanisms of a [[single-lens reflex camera]] with a solid-state [[image sensor]] and digitally records the images from the sensor.

The reflex design scheme is the primary difference between a DSLR and other digital cameras. In the reflex design, light travels through the lens and then to a mirror that alternates to send the image to either a prism, which shows the image in the optical [[viewfinder]], or the image sensor when the shutter release button is pressed. The viewfinder of a DSLR presents an image that will not differ substantially from what is captured by the [[Image sensor|camera's sensor]], as it presents it as a direct optical view through the main camera lens rather than showing an image through a separate secondary lens.

DSLRs largely replaced film-based SLRs during the 2000s. Major camera manufacturers began to transition their product lines away from DSLR cameras to [[mirrorless interchangeable-lens camera]]s (MILCs) beginning in the 2010s.

== History ==
{{see also|History of the camera#Digital cameras}}In 1969, [[Willard S. Boyle]] and [[George E. Smith]] invented charge-coupled semiconductor devices, which can be used as analog storage registers and image sensors.<ref>{{Cite journal |last1=Boyle |first1=W. S. |last2=Smith |first2=G. E. |date=April 1970 |title=Charge coupled semiconductor devices |url=https://ieeexplore.ieee.org/document/6768140 |journal=The Bell System Technical Journal |volume=49 |issue=4 |pages=587–593 |doi=10.1002/j.1538-7305.1970.tb01790.x |bibcode=1970BSTJ...49..587B |issn=0005-8580|url-access=subscription }}</ref> A [[Charge-coupled device|CCD]] (Charge-Coupled Device) imager provides a low-noise analog image signal, which is digitized when used in a digital camera. For their contribution to digital photography, Boyle and Smith were awarded the [[Nobel Prize]] for Physics in 2009.<ref>{{cite web |url=https://www.nobelprize.org/nobel_prizes/physics/laureates/2009/press.html |title=The 2009 Nobel Prize in Physics – Press Release |publisher=Nobelprize.org |date=2009-10-06 |access-date=2013-10-10 |archive-url=https://web.archive.org/web/20120516073858/http://www.nobelprize.org/nobel_prizes/physics/laureates/2009/boyle.html |archive-date=2012-05-16 |url-status=live }}</ref> 

In 1973, Fairchild developed a 100 x 100 [[pixel]] interline CCD image sensor.<ref>{{Cite journal |last=Walsh |first=L |date=April 1973 |title=A new charge-coupled area imaging device |url=http://www.imagesensors.org/Past%20Workshops/Dick%20Bredthauer%20Collection/1973%20San%20Diego/1973%2004%20Walsh.pdf |journal=CCD Applications Conference, San Diego |pages=21–22}}</ref>  This CCD was used in the first commercial CCD camera, the [https://www.digitalkameramuseum.de/en/cameras/item/fairchild-mv-100 Fairchild MV-100], which was introduced in late 1973. In 1974, Kodak scientists Peter Dillon and Albert Brault used this Fairchild CCD 202 image sensor to create the first color CCD image sensor by fabricating a red, green, and blue color filter array that was registered and bonded to the CCD.<ref>{{Cite book |last1=Dillon |first1=P.L.P. |last2=Brault |first2=A.T. |last3=Horak |first3=J.R. |last4=Garcia |first4=E. |last5=Martin |first5=T.W. |last6=Light |first6=W.A. |title=1976 International Electron Devices Meeting |chapter=Integral color filter arrays for solid state imagers |date=December 1976  |pages=400–403 |doi=10.1109/IEDM.1976.189067|s2cid=35103154 }}</ref>   In 1975, Kodak engineer [[Steven Sasson]] built the first portable, battery-operated digital still camera, which used a zoom lens from a Kodak Super 8mm movie camera and a monochrome [[Fairchild Semiconductor|Fairchild]] 100×100 pixel CCD.<ref>{{cite web |last=Jarvis |first=Audley |url=http://www.techradar.com/news/photography-video-capture/how-kodak-invented-the-digital-camera-in-1975-364822 |title=How Kodak invented the digital camera in 1975 |publisher=Techradar.com |date=2008-05-09 |access-date=2011-06-26 |url-status=dead |archive-url=https://web.archive.org/web/20120110030031/http://www.techradar.com/news/photography-video-capture/how-kodak-invented-the-digital-camera-in-1975-364822 |archive-date=2012-01-10 }}</ref>

[[File:Sony Mavica - Perspective View.jpg|thumb|Perspective view of Sony Mavica from June 1982 press release]]

The first prototype filmless SLR camera was publicly demonstrated by Sony in August 1981. The [[Sony Mavica]] (a magnetic [[still video camera]]) used a color-striped 2/3” format CCD sensor with 280K pixels, along with analog video signal processing and recording.<ref>{{Cite journal |last1=Kihara |first1=N. |last2=Nakamura |first2=K. |last3=Saito |first3=E. |last4=Kambara |first4=M. |date=August 1982 |title=The Electrical Still Camera a New Concept in Photography |journal=IEEE Transactions on Consumer Electronics |volume=CE-28 |issue=3 |pages=325–331 |doi=10.1109/TCE.1982.353928 |s2cid=45483442 |issn=1558-4127}}</ref> The Mavica electronic still camera employed a TTL single-lens reflex viewfinder, as shown in the graphic from a June 1982 Sony press release. It recorded FM-modulated analog video signals on a newly developed 2” magnetic floppy disk, dubbed the "Mavipak".

The disk format was later standardized as the "Still Video Floppy", or "SVF", so the Sony Mavica was the first "SVF-SLR" to be demonstrated, but it was not a D-SLR since it recorded analog video images rather than digital images. Starting in 1983, many Japanese companies demonstrated prototype SVF cameras, including Toshiba, Canon, Copal, Hitachi, Panasonic, Sanyo, and Mitsubishi.<ref name=":0">{{Cite journal |last1=Kriss |first1=Michael |last2=Parulski |first2=Ken |last3=Lewis |first3=David |editor-first1=John C. |editor-last1=Urbach |date=1989-08-13 |title=Critical Technologies For Electronic Still Imaging Systems |url=https://www.spiedigitallibrary.org/conference-proceedings-of-spie/1082/0000/Critical-Technologies-For-Electronic-Still-Imaging-Systems/10.1117/12.952864.full |journal=Applications of Electronic Imaging |publisher=SPIE |volume=1082 |pages=157–184 |doi=10.1117/12.952864|bibcode=1989SPIE.1082..157K |s2cid=110114088 |url-access=subscription }}</ref>

[[File:Canon RC-701 img 0828.jpg|thumb|upright|Canon RC-701 from 1986]][[File:Nikon QV1000C front-left 2015 Nikon Museum.jpg |thumb|upright|Nikon QV-1000C from 1988]]

The Canon RC-701, introduced in May 1986, was the first SVF camera (and the first SVF-SLR camera) sold in the US. It employed an SLR viewfinder and included a 2/3” format color CCD sensor with 380K pixels. It was sold along with removable 11-66mm and 50-150mm zoom lens.<ref>{{Cite journal |last=Callahan |first=Sean |date=July 1986 |title=The future arrives – by introducing an electronic still camera for photojournalists and other pros, Canon is taking photography into a new era |journal=Popular Photography |volume=93 |issue=7 |pages=62–63}}</ref>

Over the next five years, many other companies began selling SVF analog electronic cameras. These included the monochrome Nikon QV-1000C SVF-SLR camera, introduced in 1988,<ref name=":0" /> which had an F-mount for interchangeable QV Nikkor lenses. 

[[File:Nikon Nasa F4 back.jpg|thumb|upright|[[Nikon NASA F4]] back view with Electronics Box, launched on [[STS-48]] September 1991]][[File:Early digital!.jpg|thumb|upright|Kodak DCS 100, based on a [[Nikon F3]] body with Digital Storage Unit, released in May 1991]]

In 1986, the Kodak Microelectronics Technology Division developed a 1.3 MP CCD image sensor, the first with more than 1 million pixels. In 1987, this sensor was integrated with a [[Canon Inc.|Canon]] F-1 film SLR body at the Kodak Federal Systems Division to create an early DSLR camera.<ref>{{Cite news|url=https://eastman.org/historic-new-acquisition-eastman-house|title=Historic New Acquisition at Eastman House|last=Museum|first=George Eastman|date=2012-12-19|newspaper=George Eastman Museum|access-date=2016-12-30|archive-url=https://web.archive.org/web/20161231081301/https://eastman.org/historic-new-acquisition-eastman-house|archive-date=2016-12-31|url-status=dead}}</ref> The digital back monitored the camera body battery current to sync the image sensor exposure to the film body shutter.<ref>{{cite patent|title=Method and circuit for converting a conventional camera into an electro-optical camera|pubdate=1990-04-10|url=http://www.google.com/patents/US4916476|inventor-last=McGarvey|inventor-first=James E.|country=US|number=4916476}}</ref><ref>{{Cite web|url=http://eocamera.jemcgarvey.com/index.php|title=Electro-Optic Camera: The first DSLR|website=eocamera.jemcgarvey.com|access-date=2016-12-30|archive-url=https://web.archive.org/web/20160310000334/http://eocamera.jemcgarvey.com/index.php|archive-date=2016-03-10|url-status=live}}</ref> Digital images were stored on a tethered hard drive and processed for histogram feedback to the user. This camera was created for the U.S. government, and was followed by several other models intended for government use and eventually [[Kodak DCS]], a commercial DSLR series launched in 1991.<ref>{{cite journal| title = A 1.3-megapixel-resolution portable CCD electronic still camera |volume = 1448|pages = 2–12|author1=Todd A. Jackson |author2=Cynthia S. Bell | editor-first1=Winchyi | editor-first2=James R. | editor-last1=Chang | editor-last2=Milch | publisher=Proc. SPIE 1448, Camera and Input Scanner Systems 2| date=Feb 1991|doi = 10.1117/12.45340|series = Camera and Input Scanner Systems|bibcode = 1991SPIE.1448....2J| s2cid=59969890 }}</ref><ref>{{cite journal| title = Lens Evaluation for Electronic Photography|volume = 1448|pages = 59–68| first=Cynthia S.| last=Bell| editor-first1=Winchyi | editor-first2=James R. | editor-last1=Chang | editor-last2=Milch | publisher=Proc. SPIE 1448, Camera and Input Scanner Systems 59| date=Feb 1991|doi = 10.1117/12.45345|series = Camera and Input Scanner Systems|bibcode = 1991SPIE.1448...59B| s2cid=129593027 }}</ref><ref>{{cite journal |last1=Bell |first1=Cynthia S. |first2=Todd A. |last2=Jackson |date=1992 |title=Electronic Still Camera and Film Camera Comparison Experiment |url=https://www.jstage.jst.go.jp/article/photogrst1964/55/1/55_1_15/_pdf |journal=Journal of the Society of Photographic Science and Technology of Japan |volume=55 |issue=1 |pages=15–19 |access-date=2013-10-29 |archive-url=https://web.archive.org/web/20180717071235/https://www.jstage.jst.go.jp/article/photogrst1964/55/1/55_1_15/_pdf |archive-date=2018-07-17 |url-status=live }}</ref>

In 1995, Nikon co-developed the [[Nikon E series]] with Fujifilm. The E series included the [[Nikon E2]]/[[Nikon E2S|E2S]], [[Nikon E2N]]/[[Nikon E2NS|E2NS]] and [[Nikon E3]]/[[Nikon E3S|E3S]], with the E3S released in December 1999.

In the late 1990s, Sony introduced the "Digital Mavica" series of consumer digital cameras. Unlike the original analog Mavica, the Digital Mavica cameras recorded JPEG compressed image files on standard 3½-inch magnetic floppy discettes (meant to simplify camera-to-computer data transfer) and did not have an SLR viewfinder.

In 1999, Nikon announced the [[Nikon D1]]. The D1's body was similar to Nikon's professional 35&nbsp;mm film SLRs, and it had the same Nikkor lens mount, allowing the D1 to use Nikon's existing line of AI/AIS manual focus and AF lenses. Although Nikon and other manufacturers had produced digital SLR cameras for several years prior, the D1 was the first professional digital SLR that displaced Kodak's then-undisputed reign over the professional market.<ref>{{cite web| url=http://www.dpreview.com/reviews/nikond1/| title=Nikon D1 Review: 1. Intro| first=Phil| last=Askey| website=Digital Photography Review| date=2000-11-27| access-date=2009-10-25| archive-url=https://web.archive.org/web/20090929032751/http://www.dpreview.com/reviews/nikond1/| archive-date=2009-09-29| url-status=live}}</ref>

Over the next decade, other camera manufacturers entered the DSLR market, including [[Canon (company)|Canon]], [[Eastman Kodak|Kodak]], [[Fujifilm]], [[Minolta]] (later [[Konica Minolta]], and ultimately acquired by Sony), [[Pentax]] (whose camera division is now owned by [[Ricoh]]), [[Olympus Corporation|Olympus]], [[Panasonic]], [[Samsung Electronics|Samsung]], [[Sigma Corporation|Sigma]], and [[Sony]].

In January 2000, Fujifilm announced the [[FinePix S1 Pro]], the first consumer-level DSLR.

In November 2001, [[Canon (company)|Canon]] released its 4.1-megapixel [[Canon EOS-1D|EOS-1D]], the brand's first professional digital body. In 2003, Canon introduced the 6.3-[[megapixel]] [[Canon EOS 300D|EOS 300D]] SLR camera (known in the United States and Canada as the Digital Rebel and in Japan as the Kiss Digital) with an MSRP of US$999, aimed at the consumer market. Its commercial success encouraged other manufacturers to produce competing digital SLRs, lowering entry costs and allowing more amateur photographers to purchase DSLRs.

In 2004, [[Konica Minolta]] released the [[Konica Minolta Maxxum 7D]], the first DSLR with in-body [[image stabilization]]<ref>{{cite web
 |url          = http://www.dpreview.com/news/0409/04091504km7d.asp
 |title        = Konica Minolta introduces the Maxxum 7d – World's First*1 Digital SLR camera with revolutionary body-integral, anti-shake technology
 |author       = Konica Minolta
 |work         = DPReview.com
 |date         = 2004-09-15
 |access-date  = 2007-02-03
 |archive-url  = https://web.archive.org/web/20070216064720/http://www.dpreview.com/news/0409/04091504km7d.asp
 |archive-date = 2007-02-16
 |url-status   = live
}}</ref> which later become standard in [[Pentax]], [[Olympus Corporation|Olympus]], and [[Sony Alpha]] cameras.

In early 2008, [[Nikon]] released the [[Nikon D90|D90]], the first DSLR to feature video recording. Since then, all major companies have offered cameras with this functionality.

Over time, the number of megapixels in imaging sensors has increased steadily, with most companies focusing on high ISO performance, speed of focus, higher frame rates, the elimination of digital 'noise' produced by the imaging sensor, and price reductions to lure new customers.

In June 2012, Canon announced the first DSLR to feature a [[touchscreen]], the [[Canon EOS 650D|EOS 650D/Rebel T4i/Kiss X6i]]. Although this feature had been widely used on both compact cameras and [[mirrorless interchangeable-lens camera|mirrorless]] models, it had not made an appearance on a DSLR until the 650D.<ref>{{cite web |url=http://www.dpreview.com/previews/canon-eos-650d-rebel-t4i/ |title=Canon EOS 650D (Rebel T4i) Hands-on Preview |first=Andy |last=Westlake |website=[[Digital Photography Review]] |date=June 2012 |access-date=2012-06-10 |archive-url=https://web.archive.org/web/20120611012255/http://www.dpreview.com/previews/canon-eos-650d-rebel-t4i |archive-date=2012-06-11 |url-status=live }}</ref>

=== Market share ===
The DSLR market is dominated by Japanese companies, and the top five manufacturers are Japanese: Canon, Nikon, [[Olympus Corporation|Olympus]], Pentax, and [[Sony]]. Other manufacturers of DSLRs include [[Mamiya]], [[Sigma Corporation|Sigma]], [[Leica Camera|Leica]] (Germany), and [[Hasselblad]] (Swedish).

In 2007, Canon edged out Nikon with 41% of worldwide sales to the latter's 40%, followed by Sony and Olympus, each with approximately 6% [[market share]].<ref>{{cite web|url=http://www.imaging-resource.com/NEWS/1207604859.html|title=IDC on 2007 Sales: Nikon, Sony Gain in dSLRs; Samsung Up, Kodak Holds On in Digicams|publisher=[imaging-resource.com]|date=2008-04-07|access-date=2008-04-08|archive-url=https://web.archive.org/web/20080412014119/http://www.imaging-resource.com/NEWS/1207604859.html|archive-date=2008-04-12|url-status=live}}</ref> In the Japanese domestic market, Nikon captured 43.3% to Canon's 39.9%, with Pentax a distant third at 6.3%.<ref>{{cite web|url=http://www.dpreview.com/news/0801/08011105japansales.asp|title='Big two' continue to dominate Japan|website=[[Digital Photography Review|DPreview.com]]|date=2008-01-11|access-date=2008-04-08|archive-url=https://web.archive.org/web/20080420092427/http://www.dpreview.com/news/0801/08011105japansales.asp|archive-date=2008-04-20|url-status=live}}</ref>

In 2008, [[Canon (company)|Canon]]'s and [[Nikon]]'s offerings took the majority of sales.<ref>{{cite web |url=http://www.digital-slr-guide.com/canon-vs-nikon.html |title=Canon vs Nikon Digital SLR Cameras |work=Digital SLR Guide |publisher=Digital-slr-guide.com |access-date=2013-10-10 |archive-url=https://web.archive.org/web/20130928120155/http://www.digital-slr-guide.com/canon-vs-nikon.html |archive-date=2013-09-28 |url-status=live }}</ref> In 2010, [[Canon (company)|Canon]] controlled 44.5% of the DSLR market, followed by [[Nikon]] with 29.8% and Sony with 11.9%.<ref>{{cite web|url=https://www.bloomberg.com/news/2011-04-15/sony-nikon-narrow-gap-to-canon-with-new-digital-camera-models.html|title=Sony, Nikon Narrow Gap to Canon With New Digital Camera Models|publisher=[[Bloomberg L.P.|Bloomberg.com]]|date=2011-04-15|access-date=2017-03-06|archive-url=https://web.archive.org/web/20150108055506/http://www.bloomberg.com/news/2011-04-15/sony-nikon-narrow-gap-to-canon-with-new-digital-camera-models.html|archive-date=2015-01-08|url-status=live}}</ref>

For Canon and Nikon, digital SLRs were their biggest source of profit in the early 2010s. Canon's DSLRs brought in four times the profits of their compact digital cameras, while Nikon earned more from DSLRs and lenses than from any other product.<ref>{{cite web |url=http://www.dpreview.com/news/2009/10/30/canonq3profitsrise |title=Canon camera profits rise despite falling sales: Digital Photography Review |publisher=Dpreview.com |access-date=2013-10-10 |archive-url=https://web.archive.org/web/20130511013550/http://www.dpreview.com/news/2009/10/30/canonq3profitsrise |archive-date=2013-05-11 |url-status=live }}</ref><ref>{{cite magazine |last=Yasu |first=Mariko |url=http://www.businessweek.com/news/2011-09-08/canon-clinging-to-mirrors-means-opportunity-for-sony-cameras.html |title=Canon Clinging to Mirrors Means Opportunity for Sony Cameras |magazine=Businessweek |date=2011-09-08 |access-date=2013-10-10 |url-status=dead |archive-url=https://web.archive.org/web/20130528005306/http://www.businessweek.com/news/2011-09-08/canon-clinging-to-mirrors-means-opportunity-for-sony-cameras.html |archive-date=2013-05-28 }}</ref> Olympus and Panasonic have since exited the DSLR market and now focus on producing mirrorless cameras.

In 2013, after a decade of double-digit growth, DSLR (along with [[MILC]]) sales were down 15 per cent. This may be due to some low-end DSLR users choosing to use a [[smartphone]] instead. The market intelligence firm IDC predicted that Nikon would be out of business by 2018 if the trend continued, although this did not come to pass. Regardless, the market has shifted from being driven by hardware to software, and camera manufacturers have not been keeping up.<ref>{{cite web |url=http://www.eoshd.com/content/11409/consumer-dslrs-dead-5-years |title=Consumer DSLRs "dead in 5 years" |date=26 October 2013 |access-date=December 30, 2013 |archive-url=https://web.archive.org/web/20131231000018/http://www.eoshd.com/content/11409/consumer-dslrs-dead-5-years |archive-date=2013-12-31 |url-status=live }}</ref>

=== Decline and transition to mirrorless cameras ===
Beginning in the 2010s, major camera manufacturers began to transition their product lines away from DSLR cameras to [[Mirrorless camera|mirrorless interchangeable-lens cameras]] (MILCs). In September 2013, Olympus announced they would stop the development of DSLR cameras and focus on the development of MILCs.<ref>{{cite web |url=http://www.japantimes.co.jp/news/2013/12/30/business/mirrorless-cameras-offer-glimmer-of-hope-to-makers/ |title=Mirrorless cameras offer glimmer of hope to makers |date=30 December 2013 |access-date=December 31, 2013 |archive-url=https://web.archive.org/web/20131231203557/http://www.japantimes.co.jp/news/2013/12/30/business/mirrorless-cameras-offer-glimmer-of-hope-to-makers/ |archive-date=2013-12-31 |url-status=live }}</ref> [[Nikon]] announced they were ending production of DSLRs in Japan in 2020, followed by similar announcements from Canon and Sony.<ref>{{Cite web|last=Shankland|first=Stephen|title=Canon plans no new flagship DSLR models as mirrorless cameras take over|url=https://www.cnet.com/tech/computing/canons-flagship-dslr-will-be-its-last-as-mirrorless-cameras-take-over/|access-date=2022-01-13|website=CNET|language=en}}</ref><ref>{{Cite web|date=2021-06-09|title=Nikon to end single-lens reflex camera production in Japan|url=https://www.japantimes.co.jp/news/2021/06/09/business/corporate-business/nikon-production/|access-date=2022-01-13|website=The Japan Times|language=en-US}}</ref><ref>{{Cite web|title=Sony is no longer selling DSLRs|url=https://www.engadget.com/sony-is-no-longer-selling-dsl-rs-091012774.html|access-date=2022-01-13|website=Engadget|date=5 May 2021 |language=en-US}}</ref> In 2021, mirrorless cameras began to outsell DSLRs for the first time since their introduction;<ref>{{cite web | last=Dawood | first=Usman | title=Mirrorless cameras outsell DSLRs for the first time | website=Digital Camera World | date=2021-02-04 | url=https://www.digitalcameraworld.com/news/mirrorless-cameras-outsell-dslrs-for-the-first-time | access-date=2025-08-23}}</ref> this trend has continued as all major camera brands other than Pentax have ceased production of new consumer DSLR models {{As of|2025|lc=y}}.<ref>{{cite web | last=Waller | first=Joshua | title=The DSLR is dead, no really, we mean it this time (except for Pentax) | website=Amateur Photographer | date=2025-03-07 | url=https://amateurphotographer.com/latest/opinion/the-dslr-is-dead-no-really-we-mean-it-this-time-except-for-pentax/ | access-date=2025-08-23}}</ref> [[Contax]], [[Fujifilm]], [[Kodak]], [[Panasonic]], Olympus, [[Sigma Corporation|Sigma]], Sony,<ref>{{cite web | title=Did Sony Discontinue Its DSLRs? | website=Aftershoot | date=2021-05-07 | url=https://aftershoot.com/blog/did-sony-discontinue-its-dslrs/ | access-date=2025-08-23}}</ref> and [[Samsung]] all previously produced DSLRs but now either exclusively offer non-DSLR systems or have left the camera market entirely.

=== Present-day models ===
[[File:Pentax K10D front.jpg|thumb|[[Pentax K10D]] [[APS-C]] digital SLR with lens removed]]
[[File:EOS70D front.jpg|thumb|[[Canon EOS 70D]] [[APS-C]] digital SLR with lens removed]]
[[File:Nikon D850 sensor.jpg|thumb|[[Nikon D850]] [[Full-frame digital SLR|full-frame (FX)]] digital SLR camera with lens removed]]
Currently, DSLRs are widely used by consumers and professional still photographers. Well-established DSLRs currently offer a wide variety of dedicated lenses and other equipment and can be found for lower prices than newer mirrorless cameras; however, the majority of companies that historically produced DSLRs have since ceased production in favor of mirrorless systems.<ref>{{cite web | last=Waller | first=Joshua | title=The DSLR is dead, no really, we mean it this time (except for Pentax) | website=Amateur Photographer | date=2025-03-07 | url=https://amateurphotographer.com/latest/opinion/the-dslr-is-dead-no-really-we-mean-it-this-time-except-for-pentax/ | access-date=2025-08-23}}</ref> Mainstream DSLRs (in [[full-frame DSLR|full-frame]] or smaller [[image sensor format]]) are produced by [[Nikon Corporation|Nikon]] and [[Pentax]]. [[Phase One (company)|Phase One]], [[Hasselblad]], and [[Mamiya]] Leaf produce expensive, high-end [[Medium format (film)|medium-format]] DSLRs, including some with removable sensor backs. [[Konica Minolta]]'s line of DSLRs was purchased by Sony.
* Nikon offers the flagship full-frame [[Nikon D6|D6]], as well as the midrange full-frame [[Nikon D780|D780]] and [[Nikon D850|D850]] and the entry-level APS-C [[Nikon D7500|D7500]]. {{As of|2024}}, all other Nikon DSLRs have been discontinued.<ref>{{cite web | last=Schneider | first=Jaron | title=Nikon Rejects the Claim That It Is No Longer Producing F-Mount Products | website=PetaPixel | date=2024-01-25 | url=https://petapixel.com/2024/01/25/nikon-rejects-the-claim-that-it-is-no-longer-producing-f-mount-products/ | access-date=2025-08-23}}</ref>
* Leica produces the [[Leica S3|S3]], a medium format DSLR.
* Pentax currently offers APS-C and full-frame DSLRs. The APS-C cameras include the [[Pentax K-3 III|K-3 III]] and the [[Pentax KF|KF]].<ref>{{cite web | title=innovative camera technology | website=PENTAX - Official Store | date=2022-11-09 | url=https://pentax.eu/collections/aps-c-cameras | access-date=2025-08-23}}</ref> The [[Pentax K-1#K-1 II|K-1 Mark II]], announced in 2018 as successor to the [[Pentax K-1]], is the current full-frame model. All APS-C and full-frame models have extensive backward compatibility with Pentax and third-party film era lenses from about 1975, those that use the [[Pentax K mount]].

== Design ==
[[File:Olympus E-30-Cutmodel.jpg|thumb|300px|Cutaway of an [[Olympus E-30]] DSLR]]

Like SLRs, DSLRs typically use [[interchangeable lens]]es with a proprietary [[lens mount]]. A movable mechanical mirror system is switched down (to precisely a 45-degree angle) to direct light from the [[photographic lens|lens]] over a matte focusing screen via a condenser lens  and a [[pentaprism]]/[[pentamirror]] to an optical [[viewfinder]] eyepiece. Most entry-level DSLRs use a [[pentamirror]] instead of the traditional [[pentaprism]].

[[Focus (optics)|Focusing]] can be manual, by twisting the focus on the lens; or [[Autofocus|automatic]], activated by pressing half-way on the shutter release or a dedicated auto-focus (AF) button. To take an image, the mirror swings upwards in the direction of the arrow, the [[focal-plane shutter]] opens, and the image is projected and captured on the [[image sensor]]. After these actions, the shutter closes, the mirror returns to the 45-degree angle, and the built-in drive mechanism re-tensions the shutter for the next exposure.

Compared with the newer concept of [[mirrorless interchangeable-lens camera]]s, this mirror/prism system is the characteristic difference, providing direct, accurate optical preview with separate [[autofocus]] and [[Exposure (photography)|exposure]] [[Light meter|metering]] [[sensor]]s. Essential parts of all digital cameras are some [[electronics]] like [[amplifier|amplifiers]], [[analog-to-digital converter]]s, [[image processor]]s, and other [[microprocessor]]s for processing the [[digital image]], performing [[Computer data storage|data storage]], and/or driving an [[electronic display]].

=== Autofocus ===
{{Main|Phase detection autofocus}}
DSLRs typically use autofocus based on phase detection. This method allows the optimal lens position to be calculated rather than "found", as would be the case with autofocus based on contrast maximization. Phase-detection autofocus is typically faster than other passive techniques. As the phase sensor requires the same light going to the image sensor, it was previously only possible with an SLR design. However, with the introduction of focal-plane phase-detect autofocusing in mirrorless interchangeable lens cameras by Sony, Fuji, Olympus, and Panasonic, cameras can now employ both phase detect and contrast-detect AF points.

== Common features ==

=== Mode dial ===

Digital SLR cameras, along with most other digital cameras, generally have a [[mode dial]] to access standard camera settings or automatic scene-mode settings. Sometimes called a "PASM" dial, they typically provide modes such as program, aperture-priority, shutter-priority, and full manual modes. Scene modes vary from camera to camera, and these modes are inherently less customizable. They often include landscape, portrait, action, macro, night, and silhouette, among others. However, these different settings and shooting styles that "scene" mode provides can be achieved by calibrating certain settings on the camera.

=== Dust reduction systems ===
{{Main|Dust reduction system}}

A method to prevent dust from entering the chamber by using a "dust cover" filter right behind the lens mount was used by Sigma in its first DSLR, the [[Sigma SD9]], in 2002.{{citation needed|date=August 2013}}

[[Olympus Corporation|Olympus]] used a built-in sensor cleaning mechanism in its first DSLR that had a sensor exposed to air, the [[Olympus E-1]], in 2003{{citation needed|date=August 2013}} (all previous models each had a non-interchangeable lens, preventing direct exposure of the sensor to outside environmental conditions).

Several Canon DSLR cameras rely on dust reduction systems based on vibrating the sensor at ultrasonic frequencies to remove dust from the sensor.<ref>{{cite web|url=http://cpn.canon-europe.com/content/education/technical/eos_integrated_cleaning_system.do|title=Canon Professional Network – The EOS Integrated Cleaning System|author=Canon Europa N.V. and Canon Europe Ltd 2002–2015.|work=Canon Professional Network|access-date=22 August 2015|archive-url=https://web.archive.org/web/20150723040927/http://cpn.canon-europe.com/content/education/technical/eos_integrated_cleaning_system.do|archive-date=2015-07-23|url-status=live}}</ref>

=== Interchangeable lenses ===
{{Main|Photographic lens|Lenses for SLR and DSLR cameras}}
[[File:Canon EF-S 18-135mm IS.JPG|thumb|[[Canon EF-S 18-135mm lens|Canon EF-S 18-135mm]] APS-C [[zoom lens]]]]

The ability to exchange lenses, to select the best lens for the current photographic need, and to allow the attachment of specialized lenses is one of the key factors in the popularity of DSLR cameras, although this feature is not unique to the DSLR design and mirrorless interchangeable lens cameras are becoming increasingly popular. Interchangeable lenses for SLRs and DSLRs are built to operate correctly with a specific [[lens mount]] that is generally unique to each brand. A photographer will often use lenses made by the same manufacturer as the camera body (for example, [[Canon EF lens mount|Canon EF lenses]] on a [[Canon (company)|Canon]] body) although there are also many independent lens manufacturers, such as [[Sigma Corporation|Sigma]], [[Tamron]], [[Tokina]], and [[Vivitar]], that make lenses for a variety of different lens mounts. There are also lens adapters that allow a lens for one lens mount to be used on a camera body with a different lens mount, but with often reduced functionality.

Many lenses are mountable, "diaphragm-and-meter-compatible", on modern DSLRs, and on older film SLRs that use the same lens mount. However, when lenses designed for 35&nbsp; mm film or equivalently sized digital image sensors are used on DSLRs with smaller sized sensors, the image is effectively cropped and the lens appears to have a longer focal length than its stated focal length. Most DSLR manufacturers have introduced lines of lenses with image circles optimised for the smaller sensors and focal lengths equivalent to those generally offered for existing 35&nbsp; mm mount DSLRs, mostly in the wide-angle range. These lenses tend not to be completely compatible with full-frame sensors or 35&nbsp; mm film because of the smaller imaging circle<ref>{{cite web
 |url          = http://news.cnet.com/8301-13580_3-9834860-39.html
 |title        = How Nikon bettered Canon with full-frame SLRs
 |work = CNET
 |date         = 2007-12-18
 |access-date   = 2009-08-13
 |archive-url  = https://web.archive.org/web/20111113083154/http://news.cnet.com/8301-13580_3-9834860-39.html
 |archive-date = 2011-11-13
 |url-status     = live
}}</ref> and with some [[Canon EF-S lens mount|Canon EF-S lenses]], interfere with the reflex mirrors on full-frame bodies.

=== HD video capture ===

Since 2008, manufacturers have offered DSLRs which offer a movie mode capable of recording high definition motion video. A DSLR with this feature is often known as an HDSLR or DSLR video shooter.<ref>{{cite web|url=http://dslrvideoshooter.com/10-must-read-hdslr-guides-for-filmmakers/|title=10 Must Read HDSLR Guides For Filmmakers|work=DSLR Video Shooter|date=16 June 2010 |access-date=22 August 2015|archive-url=https://web.archive.org/web/20150819072553/http://dslrvideoshooter.com/10-must-read-hdslr-guides-for-filmmakers/|archive-date=2015-08-19|url-status=live}}</ref> The first DSLR introduced with an HD movie mode, the [[Nikon D90]], captures video at [[720p]]24 (1280x720 resolution at 24 [[frames per second|frame/s]]). Other early HDSLRs capture video using a nonstandard video resolution or frame rate. For example, the [[Pentax K-7]] uses a nonstandard resolution of 1536×1024, which matches the imager's 3:2 aspect ratio. The [[Canon EOS 500D]] (Rebel T1i) uses a nonstandard frame rate of 20&nbsp;frame/s at 1080p, along with a more conventional 720p30 format.

In general, HDSLRs use the full imager area to capture HD video, though not all pixels (causing video artifacts to some degree). Compared with the much smaller image sensors found in the typical camcorder, the HDSLR's much larger sensor yields distinctly different image characteristics.<ref>{{cite web|url=http://www.learn.usa.canon.com/resources/articles/2011/whats_news_eosrebel_t1i_moviemode_article.shtml|title=Canon DLC: Article: What's New in the EOS Rebel T1i: HD Movie Mode|access-date=22 August 2015|archive-url=https://web.archive.org/web/20150610223119/http://www.learn.usa.canon.com/resources/articles/2011/whats_news_eosrebel_t1i_moviemode_article.shtml|archive-date=2015-06-10|url-status=live}}</ref>   HDSLRs can achieve much shallower depth of field and superior low-light performance. However, the low ratio of active pixels (to total pixels) is more susceptible to aliasing artifacts (such as [[moiré patterns]]) in scenes with particular textures, and CMOS [[rolling shutter]] tends to be more severe. Furthermore, due to the DSLR's optical construction, HDSLRs typically lack one or more video functions found on standard dedicated camcorders, such as autofocus while shooting, powered zoom, and an electronic viewfinder/preview. These and other handling limitations prevent the HDSLR from being operated as a simple point-and-shoot camcorder, instead of demanding some level of planning and skill for location shooting.

Video functionality has continued to improve since the introduction of the HDSLR, including higher video resolution (such as [[1080p24]]) and video bitrate, improved automatic control (autofocus) and manual exposure control, and support for formats compatible with [[high-definition television]] broadcast, [[Blu-ray]] disc mastering<ref>{{cite web
 |url          = http://www.blu-raydisc.com/Assets/Downloadablefile/2b_bdrom_audiovisualapplication_0305-12955-15269.pdf
 |title        = Blu-ray Disc Format White Paper
 |date         = March 2005
 |access-date   = 2009-10-03
 |archive-url  = https://web.archive.org/web/20090326224610/http://www.blu-raydisc.com/Assets/Downloadablefile/2b_bdrom_audiovisualapplication_0305-12955-15269.pdf
 |archive-date = 2009-03-26
 |url-status     = live
}}</ref> or [[Digital Cinema Initiatives]] (DCI). The [[Canon EOS 5D Mark II]] (with the release of firmware version 2.0.3/2.0.4.<ref>{{cite web |url=http://www.canonrumors.com/2010/03/5d-mark-ii-firmware-announcement/ |title=5D Mark II Firmware Announcement |work=Canon Rumors |publisher=Canonrumors.com |date=2010-03-01 |access-date=2010-12-30 |archive-url=https://web.archive.org/web/20101224014231/http://www.canonrumors.com/2010/03/5d-mark-ii-firmware-announcement/ |archive-date=2010-12-24 |url-status=live }}</ref>) and [[Panasonic Lumix GH1]] were the first HDSLRs to offer 1080p video at 24fps, and since then the list of models with comparable functionality has grown considerably.{{Citation needed|date=April 2023}}

The rapid maturation of HDSLR cameras has sparked a revolution in digital filmmaking (referred to as "DSLR revolution"<ref name="researchgate.net">{{cite journal |last1=Nuska |first1=Petr |date=2018 |title=The DSLR Revolution and its Impact on Documentary and Ethnographic Filmmaking |url=https://www.researchgate.net/publication/331320440 |journal=Visual Ethnography |volume=7 |issue=2 |pages=24–44 |doi=10.12835/ve2018.1-0111 |access-date=2020-09-16}}</ref>), and the "Shot On DSLR" badge is a quickly growing phrase among independent filmmakers. Canon's North American TV advertisements featuring the [[Canon EOS 500D|Rebel T1i]] have been shot using the T1i itself. Other types of HDSLRs found their distinct application in the field of documentary and ethnographic filmmaking, especially due to their affordability, technical and aesthetical features, and their ability to make observation highly intimate.<ref name="researchgate.net"/> An increased number of films, television shows, and other productions are utilizing the quickly improving features. One such project was Canon's "Story Beyond the Still" contest that asked filmmakers to collectively shoot a short film in 8 chapters, with each chapter being shot over a short period of time and a winner was determined for each chapter. After 7 chapters the winners collaborated to shoot the final chapter of the story. Due to the affordability and convenient size of HDSLRs compared with professional movie cameras, [[The Avengers (2012 film)|The Avengers]] used five [[Canon EOS 5D Mark II]] and two [[Canon 7D]] to shoot the scenes from various vantage angles throughout the set and reduced the number of reshoots of complex action scenes.<ref>{{cite web |url=http://usa.canon.com/cusa/about_canon?pageKeyCode=pressreldetail&docId=0901e0248055b504 |title=Canon EOS 5D Mark II and EOS 7D Digital SLR Cameras of Choice for Stunts and Action Work on Set of "Marvel's The Avengers" |access-date=May 21, 2012 |url-status=dead |archive-url=https://web.archive.org/web/20120513205028/http://usa.canon.com/cusa/about_canon?pageKeyCode=pressreldetail&docId=0901e0248055b504 |archive-date=May 13, 2012 }}</ref>

Manufacturers have sold optional accessories to optimize a DSLR camera as a video camera, such as a shotgun-type microphone, and an External [[Electronic viewfinder|EVF]] with 1.2 million pixels.<ref>{{cite web |url=http://nofilmschool.com/2010/09/zacuto-announces-evf-viewfinder-with-70-less-resolution-than-the-redrock-micro/ |title=Zacuto Announces EVF Viewfinder With 70% Less Resolution Than the Redrock Micro? |date=30 September 2010 |publisher=NoFilmSchool |access-date=2011-01-02 |archive-url=https://web.archive.org/web/20101218054513/http://nofilmschool.com/2010/09/zacuto-announces-evf-viewfinder-with-70-less-resolution-than-the-redrock-micro/ |archive-date=2010-12-18 |url-status=live }}</ref>

=== Live preview ===
{{Main|Live preview}}
[[File:2023 Nikon D90 w trybie Live View.jpg|thumb|right|[[Nikon D90]] in Liveview mode also usable for [[720p]] [[HD video]]]]

Early DSLRs lacked the ability to show the optical viewfinder's image on the LCD display – a feature known as [[live preview]]. Live preview is useful in situations where the camera's eye-level viewfinder cannot be used, such as [[underwater photography]] where the camera is enclosed in a plastic waterproof case.

In 2000, Olympus introduced the [[Olympus E-10]], the first DSLR with live preview – albeit with an atypical fixed lens design. {{as of|2008|9|alt=In late 2008}}, some DSLRs from [[Canon (company)|Canon]], [[Nikon]], [[Olympus Corporation|Olympus]], [[Panasonic]], [[Leica Camera|Leica]], [[Pentax]], [[Samsung]] and [[Sony]] all provided continuous live preview as an option. Additionally, the Fujifilm [[FinePix S5 Pro]]<ref>{{cite web| date =July 2007| title =Fujifilm FinePix S5 Pro Review| author =Simon Joinson| website =Digital Photography Review| url =http://www.dpreview.com/reviews/fujifilms5pro/| access-date =2007-12-07| archive-url =https://web.archive.org/web/20071203201534/http://www.dpreview.com/reviews/fujifilms5pro/| archive-date =2007-12-03| url-status =live}}</ref> offers 30 seconds of live preview.

On almost all DSLRs that offer live preview via the primary sensor, the phase-detection autofocus system does not work in the live preview mode, and the DSLR switches to a slower contrast system commonly found in [[point-and-shoot camera]]s. While even phase detection autofocus requires contrast in the scene, strict contrast-detection autofocus is limited in its ability to find focus quickly, though it is somewhat more accurate.

In 2012, Canon introduced hybrid autofocus technology to the DSLR in the [[Canon EOS 650D|EOS 650D/Rebel T4i]], and introduced a more sophisticated version, which it calls "Dual Pixel CMOS AF", with the [[Canon EOS 70D|EOS 70D]]. The technology allows certain pixels to act as both contrast-detection and phase-detection pixels, thereby greatly improving autofocus speed in live view (although it remains slower than pure phase detection). While several [[Mirrorless interchangeable-lens camera|mirrorless cameras]], plus Sony's [[Sony SLT camera|fixed-mirror SLTs]], have similar hybrid AF systems, Canon is the only manufacturer that offers such technology in DSLRs.

A new feature via a separate software package introduced from Breeze Systems in October 2007, features live view from a distance. The software package is named "DSLR Remote Pro v1.5" and enables support for the [[Canon EOS 40D]] and [[Canon EOS-1D Mark III|1D Mark III]].<ref>{{cite web| date =October 2, 2007| title =Live view from a distance with DSLR Remote Pro v1.5| website =Digital Photography Review| author =dpreview.com| url =http://www.dpreview.com/news/0710/07100201breezeremote.asp| access-date =2007-10-07| archive-url =https://web.archive.org/web/20071011004913/http://www.dpreview.com/news/0710/07100201breezeremote.asp| archive-date =2007-10-11| url-status =live}}</ref>

=== Sensor size and image quality ===
{{Main|Image sensor format}}
[[File:SensorSizes.svg|thumb|275px|right|Sizes of sensors used in current digital cameras.]]

Image sensors used in DSLRs come in a range of sizes. The very largest are the ones used in "[[Medium format (film)|medium format]]" cameras, typically via a "[[Digital camera back|digital back]]" which can be used as an alternative to a film back. Because of the manufacturing costs of these large sensors, the price of these cameras is typically over $1,500 and easily reaching $8,000 and beyond {{As of|2021|02|lc=on}}.

"[[Full-frame digital SLR|Full-frame]]" is the same size as 35&nbsp;mm film (135 film, image format 24×36&nbsp;mm); these sensors are used in DSLRs such as the [[Canon EOS-1D X Mark II]], [[Canon EOS 5DS|5DS/5DSR]], [[Canon EOS 5D Mark IV|5D Mark IV]] and [[Canon EOS 6D Mark II|6D Mark II]], and the [[Nikon]] [[Nikon D5|D5]], [[Nikon D850|D850]], [[Nikon D750|D750]], [[Nikon D600#Nikon D610|D610]] and [[Nikon Df|Df]]. Most lower-cost DSLRs use a smaller sensor that is APS-C sized, which is approximately 24×16&nbsp;mm, slightly smaller than the size of an [[Advanced Photo System|APS-C]] film frame, or about 40% of the area of a full-frame sensor. Other sensor sizes found in DSLRs include the [[Four Thirds System]] sensor at 26% of full frame, APS-H sensors (used, for example, in the [[Canon EOS-1D Mark III]]) at around 61% of full frame, and the original [[Foveon X3]] sensor at 33% of full frame (although Foveon sensors since 2013 have been APS-C sized). [[Leica Camera|Leica]] offers an "S-System" DSLR with a 30×45&nbsp;mm array containing 37 million pixels.<ref>{{cite web |url=http://www.dpreview.com/news/0809/08092301_leica_s2.asp |title=Leica S2 with 56% larger sensor than full frame |publisher=Dpreview.com |date=2008-09-23 |access-date=2010-12-30 |archive-url=https://web.archive.org/web/20101217042043/http://www.dpreview.com/news/0809/08092301_leica_s2.asp |archive-date=2010-12-17 |url-status=live }}</ref> This sensor is 56% larger than a full-frame sensor.

The resolution of DSLR sensors is typically measured in megapixels. More expensive cameras and cameras with larger sensors tend to have higher megapixel ratings. A larger megapixel rating does not mean higher quality. Low light sensitivity is a good example of this. When comparing two sensors of the same size, for example, two APS-C sensors one 12.1 MP and one 18 MP, the one with the lower megapixel rating will usually perform better in low light. This is because the size of the individual pixels is larger, and more light is landing on each pixel, compared with the sensor with more megapixels. This is not always the case, because newer cameras that have higher megapixels also have better noise reduction software, and higher ISO settings to make up for the loss of light per pixel due to higher pixel density.

{| style=text-align:center;" class="wikitable"
! Type !! [[Four Thirds system|Four Thirds]] !! [[Foveon X3 sensor|Sigma Foveon<br />X3]] !! Canon [[APS-C]] !! Sony · Pentax · Sigma · Samsung<br /> [[APS-C]] / [[Nikon DX format|Nikon DX]] !! Canon [[APS-H]] !! [[Full-frame digital SLR|35&nbsp;mm Full-frame<br />/ Nikon FX]] !! Leica [[Leica Camera|S2]]!! [[Pentax 645D]]!! Phase One [[Phase One (company)|P 65+]]
|-
! Diagonal (mm)
| 21.6 || 24.9 || 26.7 || 28.2–28.4 || 33.5 || 43.2–43.3 || 54|| 55|| 67.4
|-
! Width (mm)
| 17.3 || 20.7 || 22.2 || 23.6–23.7 || 27.9 || 36 ||45|| 44|| 53.9
|-
! Height (mm)
| 13.0 || 13.8 || 14.8 || 15.6 || 18.6 || 23.9–24 || 30||33|| 40.4
|-
! Area (mm<sup>2</sup>)
|  225 || 286 || 329 || 368–370 || 519 || 860–864 || 1350||1452|| 2178
|-
! [[Crop factor]]<ref name="ReferenceA">Defined here as the ratio of the diagonal of a full 35&nbsp;frame to that of the sensor format, that is CF=diag<sub>35&nbsp;mm</sub> / diag<sub>sensor</sub>.</ref>
| 2.00 || 1.74 || 1.62 || 1.52–1.54 || 1.29 || 1.0 || 0.8||0.78|| 0.64
|}
<ref name="dpreview-sensor-sizes">{{cite web | url=http://www.dpreview.com/learn/?/key=sensor%20sizes | title=Sensor sizes | first=Vincent | last=Bockaert | website=[[Digital Photography Review]] | access-date=2007-12-06 | archive-url=https://web.archive.org/web/20071128073038/http://www.dpreview.com/learn/?%2Fkey=sensor%20sizes | archive-date=2007-11-28 | url-status=live }}</ref>

=== Depth-of-field control ===
The lenses typically used on DSLRs have a wider range of [[f-number|apertures]] available to them, ranging from as large as {{F/|0.9}} to about {{F/|32}}. Lenses for smaller sensor cameras rarely have true available aperture sizes much larger than {{F/|2.8}} or much smaller than {{F/|5.6}}.

To help extend the exposure range, some smaller sensor cameras will also incorporate an ND filter pack into the aperture mechanism.<ref>{{cite web |url=http://www.dpreview.com/news/0609/06091405_canon_g7.asp |title=Canon PowerShot G7: Digital Photography Review |publisher=Dpreview.com |date=2006-09-14 |access-date=2010-12-30 |archive-url=https://web.archive.org/web/20101227200758/http://www.dpreview.com/news/0609/06091405_canon_g7.asp |archive-date=2010-12-27 |url-status=live }}</ref>

The apertures that smaller sensor cameras have available give much more [[depth of field]] than equivalent angles of view on a DSLR. For example, a 6&nbsp; mm lens on a 2/3″ sensor digicam has a field of view similar to a 24&nbsp;mm lens on a 35&nbsp;mm camera. At an aperture of {{F/|2.8}}, the smaller sensor camera (assuming a [[crop factor]] of 4) has a similar depth of field to that 35&nbsp;mm camera set to {{F/|11}}.

=== Wider angle of view ===
{{Further|Crop factor}}
[[File:Dslr sensor comparison.jpg|300px|thumb|An APS-C format SLR (left) and a full-frame DSLR (right) show the difference in the sizes of the image sensors.]]

The [[angle of view]] of a lens depends upon its focal length and the camera's image sensor size; a sensor smaller than 35&nbsp;mm film format (36×24&nbsp;mm frame) gives a narrower angle of view for a lens of a given focal length than a camera equipped with a [[full-frame digital SLR|full-frame]] (35&nbsp; mm) sensor. As of 2017, only a few current DSLRs have full-frame sensors, including the [[Canon EOS-1D X Mark II]], [[Canon EOS 5D Mark IV|EOS 5D Mark IV]], [[Canon EOS 5DS|EOS 5DS/5DS R]], and [[Canon EOS 6D Mark II|EOS 6D Mark II]]; [[Nikon]]'s [[Nikon D5|D5]], [[Nikon D600#Nikon D610|D610]], [[Nikon D750|D750]], [[Nikon D850|D850]], and [[Nikon Df|Df]]; and the [[Pentax K-1]]. The scarcity of full-frame DSLRs is partly a result of the cost of such large sensors. [[Medium format (film)|Medium format]] size sensors, such as those used in the Mamiya ZD among others, are even larger than full-frame (35&nbsp;mm) sensors, and capable of even greater resolution, and are correspondingly more expensive.

The impact of sensor size on the field of view is referred to as the "[[crop factor]]" or "focal length multiplier", which is a factor by which a lens focal length can be multiplied to give the full-frame-equivalent focal length for a lens. Typical [[APS-C]] sensors have crop factors of 1.5 to 1.7, so a lens with a focal length of 50&nbsp;mm will give a field of view equal to that of a 75&nbsp;mm to 85&nbsp;mm lens on a [[135 film|35&nbsp;mm]] camera. The smaller sensors of Four Thirds System cameras have a crop factor of 2.0.

While the crop factor of APS-C cameras effectively ''narrows'' the angle of view of long-focus (telephoto) lenses, making it easier to take close-up images of distant objects, ''wide''-angle lenses suffer a reduction in their angle of view by the same factor.

DSLRs with "crop" sensor size have slightly more [[depth-of-field]] than cameras with 35&nbsp;mm sized sensors for a given angle of view. The amount of added depth of field for a given focal length can be roughly calculated by multiplying the depth of field by the crop factor. Shallower depth of field is often preferred by professionals for portrait work and to isolate a subject from its background.

=== Unusual features ===
On July 13, 2007, FujiFilm announced the [[FinePix IS Pro]], which uses Nikon F-mount lenses. This camera, in addition to having live preview, has the ability to record in the infrared and ultraviolet spectra of light.<ref>{{cite web |url=http://www.dpreview.com/reviews/specs/Fujifilm/fuji_ispro.asp |title=Fujifilm FinePix IS Pro digital camera specifications: Digital Photography Review |publisher=Dpreview.com |access-date=2010-12-30 |url-status=dead |archive-url=https://web.archive.org/web/20101228003144/http://www.dpreview.com/reviews/specs/FujiFilm/fuji_ispro.asp |archive-date=2010-12-28 }}</ref>

In August 2010 [[Sony Alpha|Sony]] released series of DSLRs allowing 3D photography. It was accomplished by sweeping the camera horizontally or vertically in Sweep Panorama 3D mode. The picture could be saved as ultra-wide panoramic image or as [[16:9]] 3D photography to be viewed on [[BRAVIA]] 3D television set.<ref>{{cite press release
 |title       = Sony introduces high performance DSLR cameras with Full HD video Fully featured α580 with newly developed 16.2M Exmor APS HD CMOS censor, up to 7fps shooting, and Auto HDR
 |publisher   = Sony
 |date        = 2010-08-24
 |url         = http://presscentre.sony.eu/content/detail.aspx?ReleaseID=6109&NewsAreaId=2
 |access-date  = 2010-09-12
 |url-status     = dead
 |archive-url  = https://web.archive.org/web/20100830033236/http://presscentre.sony.eu/content/Detail.aspx?ReleaseID=6109&NewsAreaID=2
 |archive-date = 2010-08-30
}}</ref><ref>{{cite web|url=http://www.sony.co.uk/product/dsi-body/dslr-a580/tab/technicalspecs|title=A580 DSLR interchangeable lens camera|access-date=2010-09-12|archive-url=https://web.archive.org/web/20110728174726/http://www.sony.co.uk/product/dsi-body/dslr-a580/tab/technicalspecs|archive-date=2011-07-28|url-status=live}}</ref>

==Comparison with other digital cameras==
The reflex design scheme is the primary difference between a DSLR and other digital cameras. In the reflex design scheme, the image captured on the camera's sensor is also the image that is seen through the viewfinder. Light travels through a single lens and a mirror is used to reflect a portion of that light through the viewfinder – hence the name "single-lens reflex". While there are variations among [[point-and-shoot camera]]s, the typical design exposes the sensor constantly to the light projected by the lens, allowing the camera's screen to be used as an [[electronic viewfinder]]. However, LCDs can be difficult to see in very bright sunlight.

Compared with some low-cost cameras that provide an optical viewfinder that uses a small auxiliary lens, the DSLR design has the advantage of being [[parallax]]-free: it never provides an off-axis view. A disadvantage of the DSLR optical viewfinder system is that when it is used, it prevents using the LCD for viewing and composing the picture. Some people prefer to compose pictures on the display&nbsp;– for them, this has become the de facto way to use a camera. Depending on the viewing position of the reflex mirror (down or up), the light from the scene can only reach either the [[viewfinder]] or the sensor. Therefore, many early DSLRs did not provide "[[live preview]]" (i.e., [[focus (optics)|focusing]], [[Framing (visual arts)|framing]], and depth-of-field preview using the display), a facility that is always available on digicams. Today most DSLRs can alternate between live view and viewing through an optical viewfinder.

===Optical view image and digitally created image===
The larger, advanced digital cameras offer a non-optical electronic through-the-lens (TTL) view, via an eye-level electronic viewfinder (EVF) in addition to the rear LCD. The difference in view compared with a DSLR is that the EVF shows a digitally created image, whereas the viewfinder in a DSLR shows an actual optical image via the reflex viewing system. An EVF image has the lag time (that is, it reacts with a delay to view changes) and has a lower resolution than an optical viewfinder but achieves parallax-free viewing using less bulk and mechanical complexity than a DSLR with its reflex viewing system. Optical viewfinders tend to be more comfortable and efficient, especially for action photography and in low-light conditions. Compared with digital cameras with [[LCD]] [[electronic viewfinder]]s, there is no time lag in the image: it is always correct as it is being "updated" at the speed of light. This is important for action or sports photography, or any other situation where the subject or the camera is moving quickly. Furthermore, the "resolution" of the viewed image is much better than that provided by an LCD or an electronic viewfinder, which can be important if manual focusing is desired for precise focusing, as would be the case in [[macro photography]] and "micro-photography" (with a [[microscope]]). An optical viewfinder may also cause less eye-strain. However, electronic viewfinders may provide a brighter display in low light situations, as the picture can be electronically amplified.

=== Performance differences ===

DSLR cameras often have image sensors of [[image sensor format|much larger size]] and often higher quality, offering lower noise compared to compact cameras,<ref>{{cite web | url = http://www.dpreview.com/learn/?/Glossary/Camera_System/sensor_sizes_01.htm | title = Sensor Sizes | access-date = 2018-11-06 | archive-url = https://web.archive.org/web/20110415004138/http://www.dpreview.com/learn/?%2FGlossary%2FCamera_System%2Fsensor_sizes_01.htm | archive-date = 2011-04-15 | url-status = live }}</ref> which is useful in low light. This advantage is shared by mirrorless cameras.

For a long time, DSLRs offered faster and more responsive performance, with less [[shutter lag]], faster [[autofocus]] systems, and higher [[frame rate]]s. Around 2016–17, some mirrorless camera models started offering competitive or superior specifications in these aspects. The downside of these cameras being that they do not have an optical viewfinder, making it difficult to focus on moving subjects or in situations where a fast burst mode would be beneficial. Other digital cameras were once significantly slower in image capture (time measured from pressing the shutter release to the writing of the digital image to the storage medium) than DSLR cameras, but this situation is changing with the introduction of faster capture memory cards and faster in-camera processing chips. Still, compact digital cameras are not suited for action, wildlife, sports, and other photography requiring a high burst rate (frames per second).

Simple point-and-shoot cameras rely almost exclusively on their built-in automation and machine intelligence for capturing images under a variety of situations and offer no manual control over their functions, a trait that makes them unsuitable for use by professionals, enthusiasts, and proficient consumers (also known as "prosumers"). [[Bridge camera]]s provide some degree of manual control over the camera's shooting modes, and some even have [[hot shoe]]s and the option to attach lens accessories such as filters and secondary converters. DSLRs typically provide the photographer with full control over all the important parameters of photography and have the option to attach additional accessories using the hot shoe.<ref>{{cite web|url=http://www.thetechlounge.com/article/308/10+Reasons+to+Buy+a+DSLR+Camera/ |title=10 Reasons to Buy a DSLR Camera |date=2006-11-05 |url-status=dead |archive-url=https://web.archive.org/web/20080523175917/http://www.thetechlounge.com/article/308/10+Reasons+to+Buy+a+DSLR+Camera/ |archive-date=2008-05-23 }}</ref> including [[hot shoe]]-mounted [[flash (photography)|flash]] units, [[battery grip]]s for additional power and hand positions, external [[light meter]]s, and remote controls. DSLRs typically also have fully automatic shooting modes.

DSLRs have a larger focal length for the same field of view, which allows the creative use of [[depth of field]] effects. However, small digital cameras can focus better on closer objects than typical DSLR lenses.

The sensors used in current DSLRs — "[[full-frame digital SLR|full-frame]]" which is the same size as 35mm film, [[APS-C]], and [[Four Thirds System]] — are much larger than most digital cameras. Entry-level compact cameras typically use sensors known as 1/2.3″, which is 3% the size of a full-frame sensor. There are fixed-lens cameras — such as [[bridge camera]]s, [[List of large sensor fixed-lens cameras|premium compact cameras]], or high-end point-and-shoot cameras — that offer sensors larger than 1/2.3″, but many still fall short of the larger sizes widely found in DSLRs. Examples include the [[Sigma DP1]], which uses a Foveon X3 sensor; the [[Leica X1]]; the Canon PowerShot G1 X, which uses a 1.5″ (18.7×14&nbsp;mm) sensor that is slightly larger than the Four Thirds standard and is 30% of a full-frame sensor; the Nikon Coolpix A, which uses an APS-C sensor of the same size as those found in the company's [[Nikon DX format|DX-format]] DSLRs; and two models from Sony, the [[Sony Cyber-shot DSC-RX100|RX100]] with a 1″-type (13.2×8.8&nbsp;mm) sensor with about half the area of Four Thirds and the full-frame [[Sony Cyber-shot DSC-RX1|Sony RX1]]. These premium compacts are often comparable to entry-level DSLRs in price,<ref>{{cite web |title = Camera Prices (US) |url = https://cameraprices.com |access-date = 2025-03-05 |quote = Premium compact camera prices are comparable to entry-level DSLRs. }}</ref> with a smaller sensor being a tradeoff for the size and weight savings.

{| style="text-align:center;" class="wikitable sortable"
! Type !! Diagonal (mm) !! Width (mm) !! Height (mm) !! Area (mm<sup>2</sup>) !! [[Crop factor]]<ref name="ReferenceA"/>
|-
! [[Four Thirds system|Four Thirds]]
| 21.6 || 17.3 || 13.0 || 225 || 2.00
|-
! [[Foveon X3 sensor|Foveon X3]] (Sigma)
| 24.9 || 20.7 || 13.8 || 286 || 1.74
|-
! [[APS-C]] (Canon)
| 26.7 || 22.2 || 14.8 || 329 || 1.62
|-
! [[APS-C]] (Pentax, Sony, [[Nikon DX format|Nikon DX]])
| 28.2–28.4 || 23.6–23.7 || 15.6 || 368–370 || 1.52–1.54
|-
! [[APS-H]] (Canon)
| 33.5 || 27.9 || 18.6 || 519 || 1.29
|-
! [[Full-frame digital SLR|Full-frame]] (Canon, Nikon FX, Pentax, Sony)
| 43.2–43.3 || 36 || 23.9–24 || 860–864 || 1.0
|-
! Leica [[Leica Camera|S2]]
| 54 || 45 || 30 || 1350 || 0.8
|-
! [[Pentax 645D]]/[[Pentax 645Z|645Z]]
| 55 || 44 || 33 || 1452 || 0.78
|-
! Phase One [[Phase One (company)|P 65+]]
| 67.4 || 53.9 || 40.4 || 2178 || 0.64
|}
<ref name="dpreview-sensor-sizes"/>

===Fixed or interchangeable lenses===
Unlike DSLRs, most digital cameras lack the option to change the lens. Instead, most compact digital cameras are manufactured with a zoom lens that covers the most commonly used fields of view. Having fixed lenses, they are limited to the focal lengths they are manufactured with, except for what is available from attachments. Manufacturers have attempted (with increasing success) to overcome this disadvantage by offering extreme ranges of focal length on models known as [[Bridge digital camera|superzooms]], some of which offer far longer focal lengths than readily available DSLR lenses.

There are now available [[Tilt–shift photography|perspective-correcting (PC)]] lenses for DSLR cameras, providing some of the attributes of view cameras. Nikon introduced the first fully manual PC lens in 1961. Recently, however, some manufacturers have introduced advanced lenses that shift and tilt and are operated with automatic aperture control.

However, since the introduction of the [[Micro Four Thirds system]] by Olympus and Panasonic in late 2008, [[mirrorless interchangeable lens camera]]s are now widely available. Hence, the option to change lenses is no longer unique to DSLRs. Cameras for the micro four-thirds system are designed with the option of a replaceable lens, and lenses that conform to this proprietary specification are accepted. Cameras for this system have the same sensor size as the [[Four Thirds System|Four-Thirds System]] but do not have the mirror and pentaprism to reduce the distance between the lens and sensor.

Panasonic released the first Micro Four Thirds camera, the Lumix DMC-G1. Several manufacturers have announced lenses for the new Micro Four Thirds mount. In contrast, older Four-Thirds lenses can be mounted with an adapter (a mechanical spacer with front and rear electrical connectors and its own internal firmware). A similar mirror-less interchangeable lens camera with an APS-C-sized sensor was announced in January 2010: the [[Samsung NX10]]. On 21 September 2011, [[Nikon Corporation|Nikon]] announced with the [[Nikon 1 series|Nikon 1]] a series of [[High speed photography|high-speed]] MILCs. A handful of [[rangefinder cameras]] also support interchangeable lenses. Six digital rangefinders exist: the [[Epson R-D1]] (APS-C-sized sensor), the [[Leica M8]] (APS-H-sized sensor), both smaller than 35&nbsp; mm film rangefinder cameras, and the [[Leica M9]], [[Leica M9-P|M9-P]], [[Leica M Monochrom|M Monochrom]] and [[Leica M (Typ 240)|M (Typ 240)]] (all full-frame cameras, with the Monochrom shooting exclusively in black-and-white).

In common with other interchangeable lens designs, DSLRs must contend with potential sensor contamination by dust particles when the lens is changed (though recent [[dust reduction]] systems alleviate this). Digital cameras with fixed lenses are not usually subject to dust from outside the camera settling on the sensor.

DSLRs generally have more significant cost, size, and weight.<ref name="10reasons_no_DSLR">{{cite web | url = http://www.thetechlounge.com/article/312/10+Reasons+NOT+to+Buy+a+DSLR+Camera/ | title = 10 Reasons Not to Buy a DSLR Camera | date = 2006-11-14 | access-date = 2007-10-17 | archive-url = https://web.archive.org/web/20071017015932/http://www.thetechlounge.com/article/312/10+Reasons+NOT+to+Buy+a+DSLR+Camera/ | archive-date = 2007-10-17 | url-status = live }}</ref> They also have louder operation, due to the SLR mirror mechanism.<ref>{{cite web | url = http://www.luminous-landscape.com/reviews/cameras/canon-s3-review.shtml | title = Review: Canon Powershot S3 IS | date = July 2006 | access-date = 2007-10-17 | archive-url = https://web.archive.org/web/20071017030751/http://www.luminous-landscape.com/reviews/cameras/canon-s3-review.shtml | archive-date = 2007-10-17 | url-status = live }}</ref> Sony's fixed mirror design manages to avoid this problem. However, that design has the disadvantage that the mirror diverts some of the light received from the lens, and thus, the image sensor receives about 30% less light compared with other DSLR designs.

== See also ==
* [[Box camera]]
* [[Full-frame DSLR]]
* [[Mirrorless camera]]
* [[Rangefinder camera]]
* [[Single-lens reflex camera]]
* [[Sony SLT camera]]
* [[Twin-lens reflex camera]]

== References ==
{{reflist}}

== External links ==
* {{Commons category-inline|Digital SLR cameras}}
{{photography}}
{{Canon DSLR cameras}}
{{Konica Minolta/Sony DSLR cameras}}
{{Nikon DSLR cameras}}
{{Olympus DSLR cameras}}
{{Pentax DSLR cameras}}
{{Sigma DSLR cameras}}
{{Kodak DSLR cameras}}
{{Fujifilm DSLR cameras}}

{{DEFAULTSORT:Digital SingleLens Reflex Camera}}
[[Category:Cameras by type]]
[[Category:Digital photography]]
[[Category:Digital single-lens reflex cameras| ]]

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