Digital camera 52797 226048199 2008-07-16T16:26:16Z 124.125.198.111 /* Video cameras */ {{Refimprove|date=July 2006}} {{wiktionary|digital camera}} [[Image:Small sipix ubt.jpeg|right|thumb|A SiPix digital camera next to a [[matchbox]] to show scale]] [[Image:Coolscan-V.jpg|right|thumb|[[Nikon]] [[D200]] [[Digital single-lens reflex camera|dSLR]] with Nikon [[film scanner]], which converts film images to digital]] [[Image:Cf-card.jpg|right|thumb|A [[CompactFlash]] (CF) card stores digital photographs]] [[Image:Hasselblad 503CW V96C.jpg|right|thumb|A [[Hasselblad]] 503CW with a digital camera back]] A '''digital camera''' is a [[camera]] that takes [[video]] or still [[photograph]]s, or both, [[digital]]ly by recording [[digital image|images]] on a light-sensitive sensor. Many compact digital still cameras can record [[sound]] and moving [[video]] as well as still [[photograph]]s. In the [[Western world|Western]] market, digital cameras outsell their [[135 film|35&nbsp;mm film]] counterparts.<ref>{{cite web |url=http://www.washingtonpost.com/wp-dyn/content/article/2006/01/11/AR2006011102323.html |title=Nikon Says It's Leaving Film-Camera Business| accessdate=2007-02-23 | date=2006-01-12 | publisher=Washington Post}}</ref> Digital cameras can include features that are not found in film cameras, such as displaying an image on the camera's screen immediately after it is recorded, the capacity to take thousands of images on a single small memory device, the ability to record video with sound, the ability to edit images, and deletion of images allowing re-use of the storage they occupied. Digital cameras are incorporated into many devices ranging from [[Personal digital assistant|PDA]]s and [[mobile phone]]s (called [[camera phone]]s) to vehicles. The [[Hubble Space Telescope]] and other [[astronomy|astronomical]] devices are essentially specialised digital cameras. ==Classification== Digital cameras can be classified into several categories: ===Compact digital cameras=== Compact cameras are designed to be small and portable; the smallest are described as ''subcompacts'' or "ultra-compacts". Compact cameras are usually designed to be easy to use, sacrificing advanced features and picture quality for compactness and simplicity; images can usually only be stored using [[Lossy compression]] ([[JPEG]]). Most have a built-in [[flash (photography)|flash]] usually of low power, sufficient for nearby subjects. [[Live preview]] is almost always used to frame the photo. They may have limited [[motion picture]] capability. Compacts often have [[Macro photography|macro]] capability, but if they have [[zoom lens|zoom]] capability the range is usually less than for [[Bridge digital camera|bridge]] and [[digital single-lens reflex camera|DSLR]] cameras. They have a greater [[depth of field]], allowing objects within a large range of distances from the camera to be in sharp focus. They are particularly suitable for casual and "snapshot" use. ===Bridge cameras=== {{main|Bridge digital camera}} ''Bridge'' or ''SLR-like'' cameras are higher-end digital cameras that physically resemble [[DSLR]]s and share with them some advanced features, but share with compacts the framing of the photo using [[live preview]] and small sensor sizes. [[Image:s9000.jpg|thumb|[[Fujifilm FinePix S9000]]]] Bridge cameras often have [[superzoom]] lenses which provide a very wide zoom range, typically between 10:1 and 18:1, which is attained at the cost of some distortions, including [[barrel distortion|barrel]] and [[pincushion distortion]], to a degree which varies with lens quality. These cameras are sometimes marketed as and confused with digital SLR cameras since the appearance is similar. Bridge cameras lack the mirror and reflex system of DSLRs, have so far been fitted with fixed (non-interchangeable) lenses (although in some cases accessory wide-angle or telephoto converters cannot be attached to the lens), can usually take movies with sound, and the scene is composed by viewing either the liquid crystal display or the [[electronic viewfinder]] (EVF). They are usually slower to operate than a true digital SLR, but they are capable of very good image quality while being more compact and lighter than DSLRs. The high-end models of this type have comparable resolutions to low and mid-range DSLRs. Many of these cameras can store images in lossless [[RAW image format|RAW]] format as an option to [[JPEG]] compression. The majority have a built-in flash, often a unit which flips up over the lens. The guide number tends to be between 11 and 15. ===Digital single lens reflex cameras=== {{main|Digital single-lens reflex cameras}} Digital single-lens reflex cameras (DSLRs) are digital cameras based on film [[single-lens reflex camera]]s (SLRs), both types are characterized by the existence of a mirror and reflex system. See the main article on [[Digital single lens reflex cameras|DSLRs]] for a detailed treatment of this category. ===Digital rangefinders=== {{main|Rangefinder camera}} A rangefinder is a user-operated optical mechanism to measure subject distance once widely used on film cameras. Most digital cameras measure subject distance automatically using acoustic or electronic techniques, but it is not customary to say that they have a rangefinder. The term ''rangefinder'' alone is sometimes used to mean a rangefinder camera, that is, a film camera equipped with a rangefinder, as distinct from an [[SLR]] or a simple camera with no way to measure distance. Information on digital rangefinder cameras specifically is [[Rangefinder camera#Digital rangefinder|here]]. ===Professional modular digital camera systems=== This category includes very high end professional equipment that can be assembled from modular components (winders, grips, lenses, etc.) to suit particular purposes. Common brands include Hasselblad and Mamiya. They were developed for medium or large format film sizes, as these captured greater detail and could be enlarged more than 35 mm. Typically these cameras are used in studios for commercial production; being bulky and awkward to carry they are rarely used in action or nature photography. They can often be converted into either film or digital use by changing out the back part of the unit, hence the use of terms such as a "digital back" or "film back". These cameras are very expensive (up to $40,000) and are typically not used by consumers. ===Line-scan camera systems=== A line-scan camera is a camera device containing a line-scan [[image sensor]] chip, and a focusing mechanism. These cameras are almost solely used in industrial settings to capture an image of a constant stream of moving material. Unlike video cameras, line-scan cameras use a single array of [[active pixel sensor|pixel sensors]], instead of a matrix of them. Data coming from the line-scan camera has a frequency, where the camera scans a line, waits, and repeats. The data coming from the line-scan camera is commonly processed by a computer, to collect the one-dimensional line data and to create a two-dimensional image. The collected two-dimensional image data is then processed by image-processing methods for industrial purposes. Line-scan technology is capable of capturing data extremely fast, and at very high image resolutions. Usually under these conditions, resulting collected image data can quickly exceed 100MB in a fraction of a second. Line-scan-camera–based integrated systems, therefore are usually designed to streamline the camera's output in order to meet the system's objective, using computer technology which is also affordable. Line-scan cameras intended for the parcel handling industry can integrate adaptive focusing mechanisms to scan six sides of any rectangular parcel in focus, regardless of angle, and size. The resulting 2-D captured images could contain, but are not limited to 1D and 2D barcodes, address information, and any pattern that can be processed via image processing methods. Since the images are 2-D, they are also [[human-readable]] and can be viewable on a computer screen. Advanced integrated systems include [[video coding]] and [[optical character recognition]] (OCR). ==Conversion of film cameras to digital== When digital cameras became common, a question many photographers asked was whether their [[film camera]]s could be converted to digital. The answer was yes and no. For the majority of 35&nbsp;mm film cameras the answer is no, the reworking and cost would be too great, especially as lenses have been evolving as well as cameras. For the most part a conversion to digital, to give enough space for the electronics and allow a liquid crystal display to preview, would require removing the back of the camera and replacing it with a custom built digital unit. Many early professional SLR cameras, such as the NC2000 and the Kodak DCS series, were developed from 35&nbsp;mm film cameras. The technology of the time, however, meant that rather than being a digital "back" the body was mounted on a large and blocky digital unit, often bigger than the camera portion itself. These were factory built cameras, however, not aftermarket conversions. A notable exception was a device called the EFS-1, which was developed by Silicon Film from c.&nbsp;1998&ndash;2001. It was intended to insert into a film camera in the place of film, giving the camera a 1.3&nbsp;MP resolution and a capacity of 24 shots. Units were demonstrated, and in 2002 the company was developing the EFS-10, a 10&nbsp;MP device that was more a true digital back. A few 35&nbsp;mm cameras have had digital backs made by their manufacturer, Leica being a notable example. [[Medium format (film)|Medium format]] and [[large format]] cameras (those using film stock greater than 35&nbsp;mm), have a low unit production, and typical digital backs for them cost over $10,000. These cameras also tend to be highly modular, with handgrips, film backs, winders, and lenses available separately to fit various needs. The very large sensor these backs use leads to enormous image sizes. The largest in early 2006 is the Phase One's P45 39&nbsp;MP imageback, creating a single TIFF image of size up to 224.6&nbsp;MB. Medium format digitals are geared more towards studio and portrait photography than their smaller DSLR counterparts, the [[ISO speed]] in particular tends to have a maximum of 400, versus 6400 for some DSLR cameras. ==History== ===Early development=== <!-- Commented out because image was deleted: [[Image:Ap steven sasson.jpg|thumb|right|[[Steven Sasson]], an Eastman [[Kodak]] engineer, with his prototype digital camera]] --> The concept of digitizing images on scanners, and the concept of digitizing video signals, predate the concept of making still pictures by digitizing signals from an array of discrete sensor elements. [[Eugene F. Lally]] of the [[Jet Propulsion Laboratory]] published the first description of how to produce still photos in a digital domain using a mosaic photosensor.<ref>[[Eugene F. Lally]], "Mosaic Guidance for Interplanetary Travel," ''Space Flight Report to the Nation'', pp. 2249–61, [[American Rocket Society]], [[New York]], October 9–15, 1961.</ref> The purpose was to provide onboard navigation information to [[astronauts]] during missions to planets. The mosaic array periodically recorded still photos of star and planet locations during transit and when approaching a planet provided additional stadiametric information for orbiting and landing guidance. The concept included camera design elements foreshadowing the first digital camera. Texas Instruments engineer [[Willis Adcock]] designed a filmless camera and applied for a patent in 1972, but it is not known whether it was ever built.<ref name="digicamhistory_1970s">U.S. patents 4057830 and 4163256 were filed in 1972 but were only later awarded in 1976 and 1977. {{cite web|url=http://www.digicamhistory.com/1970s.html|title=1970s|accessdate=2008-06-15}}</ref> The first recorded attempt at building a digital camera was in 1975 by [[Steven Sasson]], an engineer at Eastman Kodak.<ref>{{cite web | url = http://www.womeninphotography.org/Events-Exhibits/Kodak/EasyShare_3.html | work = Women in Photography International | title = Digital Photography Milestones from Kodak | accessdate = 2007-09-17}}</ref> It used the then-new solid-state CCD [[image sensor]] chips developed by [[Fairchild Semiconductor]] in 1973.<ref>{{cite book | title = The Focal Encyclopedia of Photography | edition = 4th ed. | author = Michael R. Peres | url = http://books.google.com/books?id=VYyldcYfq3MC&pg=RA1-PA16&dq=sasson+ccd+fairchild&ei=sDAFR-7YA46ApwLuvYijDQ&ie=ISO-8859-1&sig=FHJgLcIA9OrCgLxeJGpanGnMs8o | publisher = Focal Press | year = 2007 | isbn = 0240807405 }}</ref> The camera weighed 8 pounds (3.6&nbsp;kg), recorded black and white images to a cassette tape, had a resolution of 0.01&nbsp;megapixels (10,000 pixels), and took 23 seconds to capture its first image in December 1975. The prototype camera was a technical exercise, not intended for production. ===Analog electronic cameras=== Handheld electronic cameras, in the sense of a device meant to be carried and used like a handheld film camera, appeared in 1981 with the demonstration of the [[Sony Mavica]] (Magnetic Video Camera). This is not to be confused with the later cameras by Sony that also bore the Mavica name. This was an analog camera, in that it recorded pixel signals continuously, as videotape machines did, without converting them to discrete levels; it recorded television-like signals to a 2&nbsp;×&nbsp;2 inch "[[video floppy]]". In essence it was a video movie camera that recorded single frames, 50 per disk in field mode and 25 per disk in frame mode. The image quality was considered equal to that of then-current televisions. Analog cameras do not appear to have reached the market until 1986 with the Canon RC-701. Canon demonstrated a prototype of this model at the [[1984 Summer Olympics]], printing the images in the Yomiuri Shimbun, a Japanese newspaper. In the United States, the first publication to use these cameras for real reportage was USA Today, in its coverage of World Series baseball. Several factors held back the widespread adoption of analog cameras; the cost (upwards of [[United States Dollar|$]]20,000), poor image quality compared to film, and the lack of quality affordable printers. Capturing and printing an image originally required access to equipment such as a frame grabber, which was beyond the reach of the average consumer. The "video floppy" disks later had several reader devices available for viewing on a screen, but were never standardized as a computer drive. The early adopters tended to be in the news media, where the cost was negated by the utility and the ability to transmit images by telephone lines. The poor image quality was offset by the low resolution of newspaper graphics. This capability to transmit images without a satellite link was useful during the [[Tiananmen Square protests of 1989]] and the first [[Gulf War]] in 1991. US government agencies also took a strong interest in the still video concept, notably the US Navy for use as a real time air-to-sea surveillance system. The first analog camera marketed to consumers may have been the Canon RC-250 Xapshot in 1988. A notable analog camera produced the same year was the [http://www.nikon.co.jp/main/eng/portfolio/about/history/cousins/cousins16_e.htm Nikon QV-1000C], designed as a press camera and not offered for sale to general users, which sold only a few hundred units. It recorded images in [[greyscale]], and the quality in newspaper print was equal to film cameras. In appearance it closely resembled a modern digital [[single-lens reflex camera]]. Images were stored on video floppy disks. ===The arrival of true digital cameras=== The first true digital camera that recorded images as a computerized file was likely the [[Fujifilm|Fuji]] [[DS-1P]] of 1988, which recorded to a 16&nbsp;MB internal memory card that used a battery to keep the data in memory. This camera was never marketed in the United States, and has not been confirmed to have shipped even in Japan. The first commercially available digital camera was the 1990 Dycam Model&nbsp;1; it also sold as the [[Logitech]] Fotoman. It used a CCD [[image sensor]], stored pictures digitally, and connected directly to a PC for download.<ref>{{cite web | title = 1990 | work = DigiCam History Dot Com | url = http://www.digicamhistory.com/1990.html | accessdate = 2007-09-17}}</ref><ref>{{cite web | title = Dycam Model 1: The world's first consumer digital still camera | work = DigiBarn computer museum | url = http://www.digibarn.com/collections/cameras/dycam-model1/index.html}}</ref><ref>Carolyn Said, "DYCAM Model 1: The first portable Digital Still Camera", ''MacWeek'', vol. 4, No. 35, Oct. 16, 1990, p. 34.</ref> In 1991, Kodak brought to market the [[Kodak DCS-100]], the beginning of a long line of professional SLR cameras by Kodak that were based in part on film bodies, often Nikons. It used a 1.3&nbsp;megapixel sensor and was priced at $13,000. The move to digital formats was helped by the formation of the first [[JPEG]] and [[MPEG]] standards in 1988, which allowed image and video files to be compressed for storage. The first consumer camera with a liquid crystal display on the back was the [[Casio]] [[QV-10]] in 1995, and the first camera to use [[CompactFlash]] was the [[Kodak DC-25]] in 1996. The marketplace for consumer digital cameras was originally low resolution (either analog or digital) cameras built for utility. In 1997 the first megapixel cameras for consumers were marketed. The first camera that offered the ability to record [[video]] clips may have been the [[Ricoh RDC-1]] in 1995. 1999 saw the introduction of the [[Nikon D1]], a 2.74&nbsp;megapixel camera that was the first [[digital SLR]] developed entirely by a major manufacturer, and at a cost of under $6,000 at introduction was affordable by professional photographers and high end consumers. This camera also used Nikon F-mount lenses, which meant film photographers could use many of the same lenses they already owned. Also in 1999, Minolta introduced the RD-3000 D-SLR at 2.7&nbsp;megapixels. This camera found many professional adherents. Limitations to the system included the need to use Vectis lenses which were designed for APS size film. The camera was sold with 5 lenses at various focal lengths and ranges (zoom). Minolta did not produce another D-SLR until September 2004 when they introduced the Alpha 7D (Alpha in Japan, Maxxum in North America, Dynax in the rest of the world) but using the Minolta A-mount system from its 35&nbsp;mm line of cameras. 2003 saw the introduction of the [[Canon EOS 300D]], also known as the [[Digital Rebel]], a 6&nbsp;megapixel camera and the first DSLR priced under $1,000, and marketed to consumers. ==Image resolution== The [[Image resolution|resolution]] of a digital camera is often limited by the camera [[sensor]] (typically a [[Charge-coupled device|CCD]] or [[CMOS sensor]] chip) that turns light into discrete signals, replacing the job of film in traditional photography. The sensor is made up of millions of "buckets" that essentially count the number of [[photon]]s that strike the sensor. This means that the brighter the image at that point the larger of a value that is read for that [[pixel]]. Depending on the physical structure of the sensor a [[color filter array]] may be used which requires a [[demosaicing]]/interpolation algorithm. The number of resulting pixels in the image determines its "pixel count". For example, a 640x480 image would have 307,200 pixels, or approximately 307 kilopixels; a 3872x2592 image would have 10,036,224 pixels, or approximately 10 megapixels. The pixel count alone is commonly presumed to indicate the resolution of a camera, but this is a misconception. There are several other factors that impact a sensor's resolution. Some of these factors include sensor size, lens quality, and the organization of the pixels (for example, a monochrome camera without a [[Bayer filter]] mosaic has a higher resolution than a typical color camera). Many digital compact cameras are criticized for having excessive pixels, in that the sensors can be so small that the resolution of the sensor is greater than the lens could possibly deliver. [[Image:Hendys Law.jpg|thumb|Australian recommended retail price of Kodak digital cameras]] As the technology has improved, costs have decreased dramatically. Measuring the "pixels per dollar" as a basic measure of value for a digital camera, there has been a continuous and steady increase in the number of pixels each dollar buys in a new camera consistent with the principles of [[Moore's Law]]. This predictability of camera prices was first presented in 1998 at the Australian [[Photo Marketing Association|PMA]] DIMA conference by Barry Hendy and since referred to as "Hendy's Law".<ref>{{cite web | url = http://news.softpedia.com/news/Digital-Lens-Flares-43923.shtml | title = More on digital cameras | author = Bogdan Solca | work = Softpedia | date= 2007-01-08 }} </ref> Since only a few [[aspect ratio]]s are commonly used (especially 4:3 and 3:2), the number of sensor sizes that are useful is limited. Furthermore, sensor manufacturers don't manufacture every possible sensor size but take incremental steps in sizes. For example, in 2007 the three largest sensors (in terms of pixel count) used by [[Canon (company)|Canon]] are the 21.1, 16.6, and 12.8&nbsp;megapixel CMOS sensors. The following is a table of sensors commercially used in digital cameras. :{| class="wikitable" |- ! Width ! Height ! [[Aspect ratio]] ! Actual pixel count ! [[Pixel#Megapixel|Megapixels]] ! Camera examples |- | 320 | 240 | [[Image:Aspect ratio - 4x3.svg|32px|4:3 aspect ratio]] | 76,800 | 0.1 | |- | 640 | 480 | [[Image:Aspect ratio - 4x3.svg|32px|4:3 aspect ratio]] | 307,200 | 0.3 | [[Apple QuickTake|Apple QuickTake 100]] (1994) |- | 832 | 608 | [[Image:Aspect ratio - 4x3.svg|32px|4:3 aspect ratio]] | 505,856 | 0.5 | Canon Powershot 600 (1996) |- | 1,024 | 768 | [[Image:Aspect ratio - 4x3.svg|32px|4:3 aspect ratio]] | 786,432 | 0.8 | Olympus D-300L (1996) |- | 1,280 | 960 | [[Image:Aspect ratio - 4x3.svg|32px|4:3 aspect ratio]] | 1,228,800 | 1.3 | Fujifilm DS-300 (1997) |- | 1,280 | 1,024 | [[Image:Aspect ratio - 4x3.svg|32px|4:3 aspect ratio]] | 1,310,720 | 1.5 | Fujifilm MX-1700 (1999) |- | 1,600 | 1,200 | [[Image:Aspect ratio - 4x3.svg|32px|4:3 aspect ratio]] | 1,920,000 | 2 | [[Nikon Coolpix 950]] |- | 2,012 | 1,324 | [[Image:Aspect ratio - 3x2.svg|32px|3:2 aspect ratio]] | 2,663,888 | 2.74 | [[Nikon D1]] |- | 2,048 | 1,536 | [[Image:Aspect ratio - 4x3.svg|32px|4:3 aspect ratio]] | 3,145,728 | 3 | [[List of Canon products#Canon PowerShot digital cameras|Canon PowerShot A75]] |- | 2,272 | 1,704 | [[Image:Aspect ratio - 4x3.svg|32px|4:3 aspect ratio]] | 3,871,488 | 4 | [[Canon Ixus 400]] |- | 2,464 | 1,648 | [[Image:Aspect ratio - 3x2.svg|32px|3:2 aspect ratio]] | 4,060,672 | 4.1 | [[Canon EOS-1D|Canon 1D]] |- | 2,560 | 1,920 | [[Image:Aspect ratio - 4x3.svg|32px|4:3 aspect ratio]] | 4,915,200 | 5 | [[Olympus E-1]] |- | 2,816 | 2,112 | [[Image:Aspect ratio - 4x3.svg|32px|4:3 aspect ratio]] | 5,947,392 | 6 | |- | 3,008 | 2,000 | [[Image:Aspect ratio - 3x2.svg|32px|3:2 aspect ratio]] | 6,016,000 | 6 | [[Nikon D40]], [[Nikon D50|D50]], [[Nikon D70|D70, D70s]], [[Pentax K100D]] |- | 3,072 | 2,048 | [[Image:Aspect ratio - 3x2.svg|32px|3:2 aspect ratio]] | 6,291,456 | 6.3 | [[Canon EOS 300D|Canon 300D]], [[Canon EOS 10D|Canon 10D]] |- | 3,072 | 2,304 | [[Image:Aspect ratio - 4x3.svg|32px|4:3 aspect ratio]] | 7,077,888 | 7 | Olympus FE-210 |- | 3,456 | 2,304 | [[Image:Aspect ratio - 3x2.svg|32px|3:2 aspect ratio]] | 7,962,624 | 8 | [[Canon EOS 350D|Canon 350D]] |- | 3,264 | 2,448 | [[Image:Aspect ratio - 4x3.svg|32px|4:3 aspect ratio]] | 7,990,272 | 8 | [[Olympus E-500]],[[Olympus SP-350]],[[Canon PowerShot A720 IS]] |- | 3,504 | 2,336 | [[Image:Aspect ratio - 3x2.svg|32px|3:2 aspect ratio]] | 8,185,344 | 8.2 | [[Canon EOS 30D|Canon 30D]], [[Canon EOS-1D Mark II|Canon 1D II]], [[Canon EOS-1D Mark II N|Canon 1D II N]] |- | 3,520 | 2,344 | [[Image:Aspect ratio - 3x2.svg|32px|3:2 aspect ratio]] | 8,250,880 | 8.25 | [[Canon EOS 20D|Canon 20D]] |- | 3,648 | 2,736 | [[Image:Aspect ratio - 4x3.svg|32px|4:3 aspect ratio]] | 9,980,928 | 10 | [[Olympus E-410]], [[Olympus E-510]], [[Panasonic Lumix DMC-FZ50|Panasonic FZ50]] |- | 3,872 | 2,592 | [[Image:Aspect ratio - 3x2.svg|32px|3:2 aspect ratio]] | 10,036,224 | 10 | [[Nikon D40x]], [[Nikon D200]], [[Nikon D80]], [[Pentax K10D]], [[Sony Alpha A100]] |- | 3,888 | 2,592 | [[Image:Aspect ratio - 3x2.svg|32px|3:2 aspect ratio]] | 10,077,696 | 10.1 | [[Canon EOS 400D|Canon 400D]], [[Canon EOS 40D|Canon 40D]] |- | 4,064 | 2,704 | [[Image:Aspect ratio - 3x2.svg|32px|3:2 aspect ratio]] | 10,989,056 | 11 | [[Canon EOS-1Ds|Canon 1Ds]] |- | 4,256 | 2,832 | [[Image:Aspect ratio - 3x2.svg|32px|3:2 aspect ratio]] | 12,052,992 | 12.1 | [[Nikon D3]] |- | 4,288 | 2,848 | [[Image:Aspect ratio - 3x2.svg|32px|3:2 aspect ratio]] | 12,212,224 | 12.2 | [[Nikon D2X|Nikon D2Xs/D2X]],[[Nikon D300]] |- | 4,368 | 2,912 | [[Image:Aspect ratio - 3x2.svg|32px|3:2 aspect ratio]] | 12,719,616 | 12.8 | [[Canon EOS 5D|Canon 5D]] |- | 4,608 | 3,072 | [[Image:Aspect ratio - 3x2.svg|32px|3:2 aspect ratio]] | 14,155,776 | 14.2 | [[Sigma SD14]] |- | 4,992 | 3,328 | [[Image:Aspect ratio - 3x2.svg|32px|3:2 aspect ratio]] | 16,613,376 | 16.6 | [[Canon EOS-1Ds Mark II|Canon 1Ds II]] |- | 5,616 | 3,744 | [[Image:Aspect ratio - 3x2.svg|32px|3:2 aspect ratio]] | 21,026,304 | 21.1 | [[Canon EOS-1Ds Mark III|Canon 1Ds III]] |- | 7,212 | 5,142 | [[Image:Aspect ratio - 4x3.svg|32px|4:3 aspect ratio]] | 39,031,344 | 39.0 | [[Hasselblad H3D#H Series|Hasselblad H3D-39]] |} ==Methods of image capture== [[Image:Partly disassembled Lumix digital camera.jpg|thumb|This digital camera is partly disassembled. The lens assembly (bottom right) is partially removed, but the sensor (top right) still captures a usable image, as seen on the LCD screen (bottom left).]] Since the first digital backs were introduced, there have been three main methods of capturing the image, each based on the hardware configuration of the sensor and color filters. The first method is often called ''single-shot'', in reference to the number of times the camera's sensor is exposed to the light passing through the camera lens. Single-shot capture systems use either one CCD with a [[Bayer filter]] mosaic, or three separate [[image sensor]]s (one each for the [[primary additive colors]] red, green, and blue) which are exposed to the same image via a beam splitter. The second method is referred to as ''multi-shot'' because the sensor is exposed to the image in a sequence of three or more openings of the lens aperture. There are several methods of application of the multi-shot technique. The most common originally was to use a single [[image sensor]] with three filters (once again red, green and blue) passed in front of the sensor in sequence to obtain the additive color information. Another multiple shot method utilized a single CCD with a Bayer filter but actually moved the physical location of the sensor chip on the focus plane of the lens to "stitch" together a higher resolution image than the CCD would allow otherwise. A third version combined the two methods without a Bayer filter on the chip. The third method is called ''scanning'' because the sensor moves across the focal plane much like the sensor of a desktop scanner. Their ''linear'' or ''tri-linear'' sensors utilize only a single line of photosensors, or three lines for the three colors. In some cases, scanning is accomplished by rotating the whole camera; a digital [[rotating line camera]] offers images of very high total resolution. The choice of method for a given capture is determined largely by the subject matter. It is usually inappropriate to attempt to capture a subject that moves with anything but a single-shot system. However, the higher color fidelity and larger file sizes and resolutions available with multi-shot and scanning backs make them attractive for commercial photographers working with stationary subjects and large-format photographs. Recently, dramatic improvements in single-shot cameras and RAW image file processing have made single shot, CCD-based cameras almost completely predominant in commercial photography, not to mention digital photography as a whole. CMOS-based single shot cameras are also somewhat common. ==Filter mosaics, interpolation, and aliasing== [[Image:Bayer pattern on sensor.svg|thumb|The Bayer arrangement of color filters on the pixel array of an image sensor]] In most current consumer digital cameras, a [[Bayer filter]] mosaic is used, in combination with an optical [[anti-aliasing filter]] to reduce the aliasing due to the reduced sampling of the different primary-color images. A [[demosaicing]] algorithm is used to [[interpolation|interpolate]] color information to create a full array of RGB image data. Cameras that use a beam-splitter single-shot [[3CCD]] approach, three-filter multi-shot approach, or [[Foveon X3 sensor]] do not use [[anti-aliasing filter]]s, nor demosaicing. Firmware in the camera, or a software in a raw converter program such as [[Adobe DNG Converter|Adobe Camera Raw]], interprets the raw data from the sensor to obtain a full color image, because the [[RGB color model]] requires three intensity values for each pixel: one each for the red, green, and blue (other color models, when used, also require three or more values per pixel). A single sensor element cannot simultaneously record these three intensities, and so a [[color filter array]] (CFA) must be used to selectively filter a particular color for each pixel. The Bayer filter pattern is a repeating 2×2 mosaic pattern of light filters, with green ones at opposite corners and red and blue in the other two positions. The high proportion of green takes advantage of properties of the human visual system, which determines brightness mostly from green and is far more sensitive to brightness than to hue or saturation. Sometimes a 4-color filter pattern is used, often involving two different hues of green. This provides potentially more accurate color, but requires a slightly more complicated interpolation process. The color intensity values not captured for each pixel can be interpolated (or guessed) from the values of adjacent pixels which represent the color being calculated. ==Connectivity== Many digital cameras can connect directly to a computer to transfer data: *Early cameras used the [[Personal computer|PC]] [[serial port]]. [[USB]] is now the most widely used method (most cameras are viewable as [[USB mass storage device class|USB mass storage]]), though some have a [[FireWire]] port. Some cameras use [[USB PTP]] mode for connection instead of [[USB MSC]]; some offer both modes. *Other cameras use wireless connections, via [[Bluetooth]] or [[IEEE 802.11]] WiFi, such as the [[Kodak]] [[EasyShare One]]. A common alternative is the use of a [[card reader]] which may be capable of reading several types of storage media, as well as high speed transfer of data to the computer. Use of a card reader also avoids draining the camera battery during the download process, as the device takes power from the [[Universal Serial Bus|USB port]]. An external card reader allows convenient direct access to the images on a collection of storage media. But if only one storage card is in use, moving it back and forth between the camera and the reader can be inconvenient. Many modern cameras support the [[PictBridge]] standard, which allows them to send data directly to a PictBridge-capable [[computer printer]] without the need for a computer. Some DVD recorders and television sets can read memory cards used in cameras; alternatively several types of flash card readers have TV output capability. ==Modes== Many digital cameras have preset [[mode dial|modes]] for different applications. Within the constraints of correct exposure various parameters can be changed, including [[Exposure (photography)|exposure]], [[aperture]], [[focus]]ing, [[light meter]]ing, [[white balance]], and equivalent sensitivity. For example a [[portrait]] might use a wider aperture to render the background out of focus, and would seek out and focus on a human face rather than other image content. == Integration == Many devices include digital cameras built into or integrated into them. For example, mobile phones often include digital cameras; those that do are sometimes known as [[camera phone]]s. Other small electronic devices (especially those used for communication) such as [[Personal digital assistant|PDA]]s, laptops and [[BlackBerry]] devices often contain an integral digital camera. Additionally, some digital [[camcorders]] contain a digital camera built into them. Due to the limited storage capacity and general emphasis on convenience rather than image quality in such integrated or converged devices, the vast majority of these devices store images in the lossy but compact [[JPEG]] file format. ==Image data storage== Most digital cameras utilize some form of removable [[computer storage|storage]] to store image data. While the vast majority of the media types are some form of [[flash memory]] ([[CompactFlash]], [[Secure Digital card|SD]], etc.) there are storage methods that use other technologies such as [[Microdrive]]s (very small [[hard disk drive]]s), [[CD single]] (185&nbsp;[[megabyte|MB]]), and [[3.5" floppy disk]]s. Although [[JPEG]] is the most common method of compressing image data, there are other methods such as [[TIFF]] and [[RAW image format|RAW]] (the latter being highly non-standardized across brands and even models of a brand). Most cameras include [[Exchangeable image file format|Exif]] data that provides [[metadata]] about the picture. Such Exif data include [[aperture]], [[exposure time]], [[focal length]], date & time taken, and camera model. Some of the removable storage technologies include all of the following: <gallery> Image:Compactflash-512mb.png|[[CompactFlash]] (CF-I) Image:Memory Stick Front and Back.jpg|[[Memory Stick]] Image:MicroDrive1GB.jpg|[[Microdrive]] (CF-II) Image:Multi Media Card front.jpg|[[MultiMediaCard]] (MMC) Image:MiniSD memory card including adapter.jpg|[[MiniSD Card]] Image:MicroSD vs SD.jpg|[[microSD]] (right) Image:SD Cards.JPG|[[Secure Digital card]] (SD) Image:Smartmedia card closeup.jpg|[[SmartMedia]] Image:USB flash drive.jpg|[[USB flash drive]] Image:XD card 16M Fujifilm front.png|[[xD-Picture Card]] (xD) Image:Floppy disk 90mm.JPG|[[3.5" floppy disk]]s Image:Mini CD vs Normal CD comparison.jpg|[[Mini CD]] (left) </gallery> Other formats include: * Onboard [[flash memory]] &mdash; Cheap cameras and cameras secondary to the device's main use (such as a camera phone) * Video Floppy &mdash; a 2x2&nbsp;inch (50&nbsp;mm&nbsp;×&nbsp;50&nbsp;mm) floppy disk used for early analog cameras * [[PC Card]] hard drives &mdash; early professional cameras (discontinued) * [[Thermal printer]] &mdash; known only in one model of camera that printed images immediately rather than storing * FP Memory &mdash; a 2-4&nbsp;MB serial flash memory, known from the Mustek/Relisys Dimera low end cameras Most manufacturers of digital cameras do not provide drivers and software to allow their cameras to work with [[Linux]] or other [[free software]]. Still, many cameras use the standard [[USB storage]] protocol, and are thus easily usable. Other cameras are supported by the [[gPhoto]] project. ==Batteries== Digital cameras have high [[electric power|power]] requirements, and over time have become increasingly smaller in size, which has resulted in an ongoing need to develop a [[battery (electricity)|battery]] small enough to fit in the camera and yet able to power it for a reasonable length of time. Essentially two broad divisions exist in the types of batteries digital cameras use. ===Off-the-shelf=== The first is batteries that are an established off-the-shelf form factor, most commonly [[AA battery|AA]], CR2, or [[CR-V3]] batteries, with [[AAA battery|AAA batteries]] in a handful of cameras. The CR2 and CR-V3 batteries are [[lithium battery|lithium based]], and intended for single use. They are also commonly seen in camcorders. The AA batteries are far more common; however, the non-rechargeable [[alkaline]] batteries are capable of providing enough power for only a very short time in most cameras. Most consumers use AA [[Nickel metal hydride battery|Nickel metal hydride batteries]] (NiMH) (''see also [[:Category:NiMH chargers|chargers]] and [[:Category:NiMH batteries|batteries]]'') instead, which provide an adequate amount of power and are rechargeable. NIMH batteries do not provide as much power as [[lithium ion battery|lithium ion batteries]], and they also tend to discharge when not used. They are available in various [[ampere-hour]] (Ah) or [[milli]]-ampere-hour (mAh) ratings, which affects how long they last in use. Typically mid-range consumer models and some low end cameras use off-the-shelf batteries; only a very few [[Digital single-lens reflex camera|DSLR]] cameras accept them (for example, [[Sigma SD10]]). Rechargeable [[RCR-V3]] lithium-ion batteries are also available as an alternative to non-rechargeable CR-V3 batteries. ===Proprietary=== The second division is proprietary battery formats. These are built to a manufacturer's custom specifications, and can be either aftermarket replacement parts or [[Original Equipment Manufacturer|OEM]]. Almost all proprietary batteries are [[lithium ion battery|lithium ion]]. While they only accept a certain number of recharges before the battery life begins degrading (typically up to 500 cycles), they provide considerable performance for their size. A result is that at the two ends of the spectrum both high end professional cameras and low end consumer models tend to use lithium ion batteries. ==Formats== {{main|Image file formats}} Common formats for digital camera images are the Joint Photography Experts Group standard ([[JPEG]]) and Tagged Image File Format ([[TIFF]]). Many cameras, especially professional or DSLR cameras, support a [[Raw image format|Raw]] format. A raw image is the unprocessed set of pixel data directly from the camera's sensor. They are often saved in formats proprietary to each manufacturer, such as NEF for Nikon, CRW or CR2 for Canon, and MRW for Minolta. Adobe Systems has released the [[Digital Negative Specification|DNG]] format, a royalty free raw image format which has been adopted by a few camera manufacturers. Raw files initially had to be processed in specialized image editing programs, but over time many mainstream editing programs, such as Google's Picasa, have added support for raw images. Editing raw format images allows much more flexibility in settings such as white balance, exposure compensation, color temperature, and so on. In essence raw format allows the photographer to make major adjustments without losing image quality that would otherwise require retaking the picture. Formats for movies are [[AVI]], [[DV]], [[MPEG]], [[QuickTime#QuickTime file format|MOV]] (often containing motion JPEG), [[WMV]], and ASF (basically the same as WMV). Recent formats include [[MP4]], which is based on the QuickTime format and uses newer compression algorithms to allow longer recording times in the same space. Other formats that are used in cameras but not for pictures are the Design Rule for Camera Format ([[Design rule for Camera File system|DCF]]), an [[International Organization for Standardisation|ISO]] specification for the camera's internal file structure and naming, Digital Print Order Format ([[DPOF]]), which dictates what order images are to be printed in and how many copies, and the Exchangeable Image File Format ([[Exif]]), which uses metadata tags to document the camera settings and date and time for image files. ==See also== <div class="references-small" style="-moz-column-count:4; column-count:4;"> *[[Backup camera]] *[[Bluetooth]] *[[Camera phone]] *[[List Of Camera Phones]] *[[Digital photo frame]] *[[Computer printer]] *[[Digital camera memory media]] *[[Digital image editing]] *[[Digital photography]] *[[Four Thirds System]] *[[Bridge digital camera]] *[[List of digital camera brands]] *[[Mobile Imaging and Printing Consortium]] *[[Personal storage device]] *[[PictBridge]] *[[Picture Transfer Protocol]] USB PTP vs [[USB MSC]] *[[Still video camera]] *[[Underwater photography]] *[[Andor Technology]] Scientific Digital Cameras *[[Webcam]] </div> ==References== {{reflist}} ==External links== {{commonscat|Digital cameras}} * [http://products.howstuffworks.com/digital-cameras-make-photography-a-snap-article.htm Howstuffworks Digital Cameras] * [http://www.spicyedition.com/archive/news/240048_firstdigital09.html The first digital camera] involving Kodak engineer [[Steven Sasson]]. * [http://www.digicamhistory.com Year-by-year developments up to 1998 and images of several types of cameras] * Article about [http://netzreport.googlepages.com/hidden_data_in_jpeg_files.html hidden data in JPEG files] produced by digital cameras * [http://www.canona650.com/ canon a650] Digital Camera History * [http://6mpixel.org/en/ More megapixels does not necessarily produce better images] * [http://www.teaser.fr/~hfiguiere/linux/digicam.html Digital Camera support for UNIX, Linux and BSD] * [http://www.faqs.org/docs/Linux-HOWTO/USB-Digital-Camera-HOWTO.html USB Digital Camera HOWTO] for Linux * [http://andrea.eric.free.fr/eric/static/en/Frame-RD-Activities-System-Analysis.html Architecture of a still-motion-/picture digital camera] [[Category:Digital photography]] [[Category:Digital cameras| ]] [[ar:كاميرا رقمية]] [[bs:Digitalni fotoaparat]] [[bg:Цифров фотоапарат]] [[ca:Càmera digital]] [[cs:Digitální fotoaparát]] [[da:Digitalkamera]] [[de:Digitalkamera]] [[el:Ψηφιακή φωτογραφική μηχανή]] [[es:Cámara digital]] [[eo:Cifereca fotilo]] [[eu:Argazki-kamera digital]] [[fa:دوربین دیجیتال]] [[fr:Appareil photographique numérique]] [[fur:Fotocjamare digjitâl]] [[ko:디지털 카메라]] [[hr:Digitalna kamera]] [[id:Kamera digital]] [[is:Stafræn ljósmyndun]] [[it:Fotocamera digitale]] [[kk:Сандық камера]] [[hu:Digitális fényképezőgép]] [[nl:Digitale camera]] [[ja:デジタルカメラ]] [[no:Digitalkamera]] [[pl:Cyfrowy aparat fotograficzny]] [[pt:Câmera digital]] [[ru:Цифровой фотоаппарат]] [[simple:Digital camera]] [[sk:Digitálny fotoaparát]] [[fi:Digitaalikamera]] [[sv:Digitalkamera]] [[th:กล้องดิจิทัล]] [[vi:Máy ảnh số]] [[tr:Dijital fotoğraf makinesi]] [[vec:Fotocamara digital]] [[zh:数码照相机]]