A digital camera is an electronic device used to capture and store photographs digitally, instead of using photographic film like conventional cameras, or recording images in an analog format to magnetic tape like many video cameras.Modern compact digital cameras are typically multifunctional, with some devices capable of recording sound and/or video as well as photographs. In the Western market, digital cameras now outsell their 35 mm film counterparts.[1]
Classification
Digital cameras can be classified into several categories:
Video cameras
Video cameras are classified as devices whose main purpose is to record moving images.Professional video cameras such as those used in television and movie production. These typically have multiple image sensors (one per color) to enhance resolution and color gamut. Professional video cameras usually do not have a built-in VCR or microphone.
Camcorders used by amateurs. They generally include a microphone to record sound, and feature a small liquid crystal display to watch the video during taping and playback.
Webcams are digital cameras attached to computers, used for video conferencing or other purposes. Webcams can capture full-motion video as well, and some models include microphones or zoom ability.
In addition, many Live-Preview Digital cameras have a "movie" mode, in which images are continuously acquired at a frame rate sufficient for video
Live-preview digital cameras
Canon PowerShot A95 with CompactFlash card loaded
Main article: Live-preview digital camera
The term digital still camera (DSC) most commonly refers to the class of live-preview digital cameras, cameras that use an electronic screen as the principal means of framing and previewing before taking the photograph. All use either a charge-coupled device (CCD) or a CMOS image sensor to sense the light intensities across the focal plane.
Many modern live-preview cameras have a movie mode, and a growing number of camcorders can take still photographs. However, even a low-end live-preview camera can take better still pictures than a mid-range video camera, and mid-range live-preview cameras have much lower video quality than low-end video cameras; that is, products are not generally optimized for both still and video photography, due to their different requirements.
Among live-preview cameras, most have a rear liquid crystal display for both preview and reviewing photographs. Transfers to a computer are commonly carried out using the USB mass storage device class (so that the camera appears as a drive) or using the Picture Transfer Protocol (PTP) and its derivatives; in addition, Firewire is sometimes supported.
The live-preview cameras are typically divided into compact (and subcompact) and bridge cameras
Compact digital cameras
Also called digicams, this encompasses most digital cameras. They are characterized by great ease in operation and easy focusing; this design allows for limited motion picture capability. They tend to have significantly smaller zooms than bridge and DSLR cameras. They have an extended depth of field. This allows objects at a larger range of depths to be in focus, which accounts for much of their ease of use. They excel in landscape photography and casual use. They typically save pictures in only the JPEG file format. All but the cheapest models have a built-in flash, although its guide number tends to be very low, perhaps just 6 or 8.
Bridge cameras
Main article: Bridge digital camera
Bridge or SLR-like cameras form a general group of higher-end live-preview cameras that physically resemble DSLRs and share with these some advanced features, but share with compacts the live-preview design and small sensor sizes.
Bridge cameras tend to have superzoom lenses, which compromises – in varying degrees, depending on the quality of the zoom lens – a "do it all" ability with barrel distortion and pincushioning. These cameras are sometimes marketed as and confused with digital SLR cameras since the bodies resemble each other. The distinguishing characteristics are that bridge cameras lack the mirror and reflex system of DSLRs, have so far been always produced with only one single sealed (non-interchangeable) lens (but accessory wide angle or telephoto converters can be attached to the front of the sealed lens), can usually take movies, record audio and the scene composition is done with either the liquid crystal display or the electronic viewfinder (EVF). The overall performance tends to be slower 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 the these cameras can save in JPEG or RAW format. 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 article: Digital single-lens reflex cameras
Digital single-lens reflex cameras (DSLRs) are digital cameras based on film single-lens reflex cameras (SLRs), both types are characterized by the existence of a mirror and reflex system. See the main article on DSLRs for a detailed treatment of this category.
Digital rangefinders
Main article: Rangefinder camera
A rangefinder is a focusing mechanism once widely used on film cameras, but much less common in digital cameras. The term rangefinder alone is often used to mean a rangefinder camera, that is, a camera equipped with a rangefinder.
For information on digital rangefinders specifically, check the digital rangefinder section in the main article linked above.
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 makes 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 35mm.
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 seen in the hands of consumers.
History
Early development
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.[2] 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 designed a filmless analog camera in 1972, but it is not known if it was ever built. The first recorded attempt at building a digital camera was by Steven Sasson, an engineer at Eastman Kodak.[3] It used the then-new solid-state CCD image sensor chips developed by Fairchild Semiconductor in 1973.[4] The camera weighed 8 pounds (3.6 kg), recorded black and white images to a cassette tape, had a resolution of 0.01 megapixel (10,000 pixels), and took 23 seconds to capture its first image in December of 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 based on television technology that recorded to a 2 × 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 this model at the 1984 Olympics, printing the images in newspapers. Several factors held back the widespread adoption of analog cameras; the cost (upwards of $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.
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 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 Fuji DS-1P of 1988, which recorded to a 16 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 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.[5][6][7]
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 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 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 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 35mm line of cameras.
2003 saw the introduction of the Canon 300D, also known as the Digital Rebel, a 6 megapixel camera and the first DSLR priced under $1,000, and marketed to consumers.
Image resolution
The resolution of a digital camera is often limited by the camera sensor (usually a charge-coupled device or CCD 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 collect charge in response to light. Generally, these buckets respond to only a narrow range of light wavelengths, due to a color filter over each. Each one of these buckets is called a pixel, and a demosaicing/interpolation algorithm is needed to turn the image with only one wavelength range per pixel into an RGB image where each pixel is three numbers to represent a complete color.
The one attribute most commonly compared on cameras is the pixel count. Due to the ever increasing sizes of sensors, the pixel count is into the millions, and using the SI prefix of mega- (which means 1 million) the pixel counts are given in megapixels. For example, an 8.0 megapixel camera has 8.0 million pixels.
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 too many pixels, in that the sensors can be so small that the resolution of the sensor is greater than the lens could possibly deliver.
Excessive pixels can even lead to a decrease in image quality. As each pixel sensor gets smaller it is catching fewer photons, and so the signal-to-noise ratio will decrease. This decrease leads to noisy pictures, poor shadow region quality and generally poorer-quality pictures.
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 PMA DIMA conference by Barry Hendy and since referred to as "Hendy's Law".[8]
Methods of image capture
This digital camera is partly disassembled. The lens assembly (bottom right) is 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 it, or three separate image sensors (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 of course 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.
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 it, or three separate image sensors (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 of course 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
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 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 filters, nor demosaicing.
Firmware in the camera, or a software in a raw converter program such as 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.
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 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 filters, nor demosaicing.
Firmware in the camera, or a software in a raw converter program such as 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 PC serial port. USB is now the most widely used method ( Most cameras are viewable as 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 Wi-Fi, such as the Kodak EasyShare One.
Early cameras used the PC serial port. USB is now the most widely used method ( Most cameras are viewable as 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 Wi-Fi, 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 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 offer the PictBridge standard, which allows sending data directly to printers without the need of a computer.
Many modern cameras offer the PictBridge standard, which allows sending data directly to printers without the need of a computer.
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 phones. Other small electronic devices (especially those used for communication) such as PDAs, 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.
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.
Storage
Digital cameras need memory to store data. A wide variety of storage media has been used. These include:
Onboard flash memory
Cheap cameras and cameras secondary to the device's main use (such as a camera phone).
3.5" floppy disks
Mainly the Sony Mavica line of the late 1990s.
Video Floppy
A 2x2 inch (50 mm × 50 mm) floppy disk used for early analog cameras.
PC Card hard drives
Early professional cameras, discontinued.
CD single or DVD
a 185 MB small form factor CD, most commonly seen in the Sony CD-1000.
Thermal printer
Known only in one model of camera that printed images immediately rather than storing
Onboard flash memory
Cheap cameras and cameras secondary to the device's main use (such as a camera phone).
3.5" floppy disks
Mainly the Sony Mavica line of the late 1990s.
Video Floppy
A 2x2 inch (50 mm × 50 mm) floppy disk used for early analog cameras.
PC Card hard drives
Early professional cameras, discontinued.
CD single or DVD
a 185 MB small form factor CD, most commonly seen in the Sony CD-1000.
Thermal printer
Known only in one model of camera that printed images immediately rather than storing
Memory cards
CompactFlash cards/Microdrives
Typically higher end professional cameras. The microdrives are actual hard drives in the CompactFlash form factor. Adapters exist to allow using SD cards in a CompactFlash device. CompactFlash cards are much larger than most cards, but have an extremely quick data transfer time.
Typically higher end professional cameras. The microdrives are actual hard drives in the CompactFlash form factor. Adapters exist to allow using SD cards in a CompactFlash device. CompactFlash cards are much larger than most cards, but have an extremely quick data transfer time.
A flash memory card in a small form factor that is gradually supplanting CompactFlash. The original storage limit was 2 GB, which is being supplanted by 4 GB cards. 4 GB cards are not recognized in all cameras as a revision was made to the SD standard as SDHC (SD High Capacity). The cards also have to be formatted in the FAT32 file format while many older cameras use FAT16 which has a 2 GB partition limit.
MiniSD Card
A smaller (slightly less than half-size) card used in devices such as camera phones.
MicroSD Card
A smaller yet (less than a quarter size) version of the SD card. Used in camera phones.
xD-Picture Card
Developed by Fuji and Olympus in 2002, a format smaller than an SD card.
SmartMedia
A now obsolete format that competed with CompactFlash, and was limited to 128 MB in capacity. One of the major differences was that SmartMedia had the memory controller built in the reading device, while in CompactFlash it was in the card. The xD picture card was developed as a replacement for SmartMedia.
FP Memory
A 2-4 MB serial flash memory, known from the Mustek/Relisys Dimera low end cameras.
MiniSD Card
A smaller (slightly less than half-size) card used in devices such as camera phones.
MicroSD Card
A smaller yet (less than a quarter size) version of the SD card. Used in camera phones.
xD-Picture Card
Developed by Fuji and Olympus in 2002, a format smaller than an SD card.
SmartMedia
A now obsolete format that competed with CompactFlash, and was limited to 128 MB in capacity. One of the major differences was that SmartMedia had the memory controller built in the reading device, while in CompactFlash it was in the card. The xD picture card was developed as a replacement for SmartMedia.
FP Memory
A 2-4 MB serial flash memory, known from the Mustek/Relisys Dimera low end cameras.
Batteries
Digital cameras have high power requirements, and over time have become increasingly smaller in size, which has resulted in an ongoing need to develop a 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.
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, CR2, or CR-V3 batteries, with AAA batteries in a handful of cameras. The CR2 and CR-V3 batteries are 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 batteries (NiMH) (see also chargers and batteries) instead, which provide an adequate amount of power and are rechargeable. NIMH batteries do not provide as much power as 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 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 OEM. Almost all proprietary batteries are 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.
Autonomous devices
An autonomous device, such as a PictBridge printer, operates without need of a computer. The camera connects to the printer, which then downloads and prints its images. Some DVD recorders and television sets can read memory cards too. Several types of flash card readers also have a TV output capability.
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 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, CR2 for Canon, and MRW for Minolta. Adobe Systems has released the 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 have added support for them, such as Google's Picasa. 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 make major adjustments without losing image quality that would otherwise require retaking the picture.
Formats for movies are AVI, DV, MPEG, 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 (DCF), an 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.
Many cameras, especially professional or DSLR cameras, support a 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, CR2 for Canon, and MRW for Minolta. Adobe Systems has released the 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 have added support for them, such as Google's Picasa. 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 make major adjustments without losing image quality that would otherwise require retaking the picture.
Formats for movies are AVI, DV, MPEG, 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 (DCF), an 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
Backup camera
Bluetooth
Camera phone
Digital photo frame
Computer printer
Digital camera memory media
Digital image editing
Digital photography
Four Thirds System
Live-Preview Digital camera
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
Backup camera
Bluetooth
Camera phone
Digital photo frame
Computer printer
Digital camera memory media
Digital image editing
Digital photography
Four Thirds System
Live-Preview Digital camera
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
References
^ Nikon Says It's Leaving Film-Camera Business. Washington Post (2006-01-12). Retrieved on 2007-02-23.
^ 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.
^ Digital Photography Milestones from Kodak. Women in Photography International. Retrieved on 2007-09-17.
^ Michael R. Peres (2007). The Focal Encyclopedia of Photography, 4th ed., Focal Press. ISBN 0240807405.
^ 1990. DigiCam History Dot Com. Retrieved on 2007-09-17.
^ Dycam Model 1: The world's first consumer digital still camera. DigiBarn computer museum.
^ Carolyn Said, "DYCAM Model 1: The first portable Digital Still Camera", MacWeek, vol. 4, No. 35, Oct. 16, 1990, p. 34.
^ Bogdan Solca (8 January 2007). More on digital cameras. Softpedia.
^ Nikon Says It's Leaving Film-Camera Business. Washington Post (2006-01-12). Retrieved on 2007-02-23.
^ 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.
^ Digital Photography Milestones from Kodak. Women in Photography International. Retrieved on 2007-09-17.
^ Michael R. Peres (2007). The Focal Encyclopedia of Photography, 4th ed., Focal Press. ISBN 0240807405.
^ 1990. DigiCam History Dot Com. Retrieved on 2007-09-17.
^ Dycam Model 1: The world's first consumer digital still camera. DigiBarn computer museum.
^ Carolyn Said, "DYCAM Model 1: The first portable Digital Still Camera", MacWeek, vol. 4, No. 35, Oct. 16, 1990, p. 34.
^ Bogdan Solca (8 January 2007). More on digital cameras. Softpedia.
External links
Howstuffworks Digital Cameras
The first digital camera involving Kodak engineer Steven Sasson.
Year-by-year developments up to 1998 and images of several types of cameras123e
Article about hidden data in JPEG files produced by digital cameras
Digital Camera support for UNIX, Linux and BSD
USB Digital Camera HOWTO for Linux
Comprehensive digital camera guide: how do you choose your digital camera?
Architecture of a still-motion-/picture digital camera
Pages with Reviews
Digital Photography Review, digital camera news and detailed reviews, has a frontend to query the database for specific features which can really come in handy
Digital Camera Resource index of reviews of recent and old digital cameras
DigitalCameraInfo.com digital camera reviews with scientific testing
steves-digicams.com with lots of digital camera reviews
Logicamera.com awesome Canon, Olympus and Nikon digital camera reviews.
Howstuffworks Digital Cameras
The first digital camera involving Kodak engineer Steven Sasson.
Year-by-year developments up to 1998 and images of several types of cameras123e
Article about hidden data in JPEG files produced by digital cameras
Digital Camera support for UNIX, Linux and BSD
USB Digital Camera HOWTO for Linux
Comprehensive digital camera guide: how do you choose your digital camera?
Architecture of a still-motion-/picture digital camera
Pages with Reviews
Digital Photography Review, digital camera news and detailed reviews, has a frontend to query the database for specific features which can really come in handy
Digital Camera Resource index of reviews of recent and old digital cameras
DigitalCameraInfo.com digital camera reviews with scientific testing
steves-digicams.com with lots of digital camera reviews
Logicamera.com awesome Canon, Olympus and Nikon digital camera reviews.
Retrieved from "http://en.wikipedia.org/wiki/Digital_camera"
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Categories: Articles needing additional references from July 2006 Digital photography Digital cameras
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