The reflex design scheme is the primary difference between a DSLR and other digital cameras. In the reflex design, light travels through the lens, then to a mirror that alternates to send the image to either the or the image sensor. By using only one lens, the viewfinder of a DSLR presents an image that will not differ substantially from what is captured by the. A DSLR differs from non-reflex single-lens digital cameras in that the viewfinder presents a direct optical view through the lens, rather than being captured by the camera's image sensor and displayed by a digital screen. DSLRs largely replaced film-based SLRs during the 2000s, and despite the rising popularity of system cameras in the early 2010s, DSLRs remain the most common type of in use as of 2018. Like SLRs DSLRs typically use 1 with a proprietary. Most of the use a instead of the traditional. To take an image, the mirror swings upwards in the direction of the arrow, the 3 opens, and the image is projected and captured on the 4 , after which 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. Phase-detection autofocus Main article: DSLRs typically use autofocus based on phase detection. 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. 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. Professional DSLRs seldom contain automatic scene modes as professionals often do not require these and professionals know how to achieve the looks they want. Several Canon DSLR cameras rely on dust reduction systems based on vibrating the sensor at ultrasonic frequencies to remove dust from the sensor. Interchangeable lenses APS-C The ability to exchange lenses, to select the best lens for the current photographic need, and to allow the attachment of specialised 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. A photographer will often use lenses made by the same manufacturer as the camera body for example, on a body although there are also many independent lens manufacturers, such as , , , and 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. However, when lenses designed for 35 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 mm mount DSLRs, mostly in the wide angle range. These lenses tend not to be completely compatible with full frame sensors or 35 mm film because of the smaller imaging circle and, with some , 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. The first DSLR introduced with an HD movie mode, the , captures video at 24 1280x720 resolution at 24. Other early HDSLRs capture video using a nonstandard video resolution or frame rate. For example, the uses a nonstandard resolution of 1536×1024, which matches the imager's 3:2 aspect ratio. 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. 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 moire patterns in scenes with particular textures, and CMOS tends to be more severe. These and other handling limitations prevent the HDSLR from being operated as a simple point-and-shoot camcorder, instead 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 and video bitrate, improved automatic control autofocus and manual exposure control, and support for formats compatible with broadcast, disc mastering or DCI. The with the release of firmware version 2. Canon's North American TV advertisements featuring the have been shot using the T1i itself. An increased number of films, documentaries, television shows, and other productions are utilizing the quickly improving features. 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, used five and two to shoot the scenes from various vantage angles throughout the set and reduced the number of reshoots of complex action scenes. Live preview is useful in situations where the camera's eye-level viewfinder cannot be used, such as where the camera is enclosed in a plastic waterproof case. In 2000, Olympus introduced the , the first DSLR with live preview — albeit with an atypical fixed lens design. In late 2008 , some DSLRs from , , , , , , and all provided continuous live preview as an option. Additionally, the Fujifilm offers 30 seconds of live preview. 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. 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 , plus Sony's , have similar hybrid AF systems, Canon is the only manufacturer that offers such a technology in DSLRs. A new feature via a separate software package introduced from Breeze Systems in October 2007, features live view from a distance. Larger sensor sizes and better image quality Drawing showing the relative sizes of sensors used in current digital cameras. Image sensors used in DSLRs come in a range of sizes. Most modern DSLRs use a smaller sensor that is APS-C sized, which is approximately 22×15 mm, slightly smaller than the size of an film frame, or about 40% of the area of a full-frame sensor. Other sensor sizes found in DSLRs include the sensor at 26% of full frame, APS-H sensors used, for example, in the at around 61% of full frame, and the original sensor at 33% of full frame although Foveon sensors since 2013 have been APS-C sized. 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. 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. To help extend the exposure range, some smaller sensor cameras will also incorporate an ND filter pack into the aperture mechanism. The apertures that smaller sensor cameras have available give much more than equivalent angles of view on a DSLR. Wider angle of view An APS-C format SLR left and a full-frame DSLR right show the difference in the size of the image sensors. The of a lens depends upon its focal length and the camera's image sensor size; a sensor smaller than 35 mm film format 36×24 mm frame gives a narrower angle of view for a lens of a given focal length than a camera equipped with a 35 mm sensor. As of 2017, only a few current DSLRs have full-frame sensors, including the , , , and ; 's , , , , and ; and the. The scarcity of full-frame DSLRs is partly a result of the cost of such large sensors. Typical sensors have crop factors of 1. The smaller sensors of Four Thirds System cameras have a crop factor of 2. 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. 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 , 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. In August 2010 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 3D photography to be viewed on 3D television set. CCD would allow the rapid development of digital photography. For their contribution to digital photography Boyle and Smith were awarded the for Physics in 2009. In 1975 Kodak engineer invented the first digital still camera, which used a 100×100. On August 25, 1981 Sony unveiled a prototype of the. This camera was an analog electronic camera that featured interchangeable lenses and a SLR viewfinder. In 1986, the Kodak Microelectronics Technology Division developed a 1. In 1987, this sensor was integrated with a Canon F-1 film SLR body at the Kodak Federal Systems Division to create the first DSLR camera. The digital back monitored the camera body battery current to sync the image sensor exposure to the film body shutter. Digital images were stored on a tethered hard drive and processed for histogram feedback to the user. This first camera was created for the U. Government, and was followed by several other models intended for government use, and eventually the first commercial DSLR, launched by Kodak in 1991. In 1995, Nikon co-developed the with Fujifilm. In 1999, Nikon announced the. 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. Over the next decade, other camera manufacturers entered the DSLR market, including , , , later , and ultimately acquired by Sony , whose camera division is now owned by , , , , , and. In January 2000, Fujifilm announced the , the first consumer-level DSLR. In November 2001, released its 4. In 2003, Canon introduced the 6. Its commercial success encouraged other manufacturers to produce competing digital SLRs, lowering entry costs and allowing more amateur photographers to purchase DSLRs. In 2004, released the , the first DSLR with in-body which later on become standard in , and cameras. In early 2008, released the , the first DSLR to feature video recording. Since then all major companies offer cameras with this functionality. Since then the number of megapixels in imaging sensors have 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 , the. Although this feature had been widely used on both compact cameras and models, it had not made an appearance in a DSLR until the 650D. Market share The DSLR market is dominated by Japanese companies and the top five manufacturers are Japanese: Canon, Nikon, , Pentax, and. Other manufacturers of DSLRs include , , German , and 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%. In the domestic market, Nikon captured 43. In 2008, 's and 's offerings took the majority of sales. In 2010, controlled 44. For Canon and Nikon, digital SLRs are their biggest source of profits. For Canon, their DSLRs brought in four times the profits from compact digital cameras, while Nikon earned more from DSLRs and lenses than with any other product. 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 sales are down 15 percent. This may be due to some low-end DSLR users choosing to use a instead. The market intelligence firm IDC predicts Nikon will be out of business in five years if the trend continues. The market has shifted from being driven by hardware to software, and camera manufacturers have not been keeping up. To illustrate the trend, in September 2013 Olympus announced they would stop development of DSLR cameras and will focus on the development of MILC. Present-day models digital SLR camera Currently DSLRs are widely used by consumers and professional still photographers. Well established DSLRs currently offer a larger variety of dedicated lenses and other. Mainstream DSLRs in or smaller are produced by , , , and. All Canon DSLRs with three- and four-digit model numbers, as well as the 7D Mark II, have APS-C sensors. The 6D, 5D series, and 1D X are full-frame. As of 2018 , all current Canon DSLRs use sensors. These models offer extensive backwards compatibility, accepting all lenses, which started being made in 1975. Pentax also offers the , which is a medium format camera, and, like Pentax' medium format film cameras, compatible with Pentax' 645 system lenses. In 2016, Pentax introduced its first full-frame DSLR, the , with the successor announced in 2018. This is claimed to give higher colour resolution, although headline pixel counts are lower than conventional Bayer-sensor cameras. It currently offers the entry-level and the professional. Sigma is the only DSLR manufacturer which sells lenses for other brands' lens mounts. The α series, whether traditional SLRs or SLTs, offers in-body sensor-shift and retains the Minolta AF lens mount. As of July 2017 , the lineup included the Alpha 68, the semipro , and the professional full-frame. The reduced number of moving parts also makes for faster shooting speeds for its class. This arrangement means that the SLT cameras use an electronic viewfinder as opposed to an optical viewfinder, which some consider a disadvantage, but does have the advantage of a live preview of the shot with current settings, anything displayed on the rear screen is displayed on the viewfinder, and handles bright situations well. 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 view finder. Light travels through a single lens and a mirror is used to reflect a portion of that light through the view finder — hence the name Single Lens Reflex. While there are variations among point-and-shoot cameras, the typical design exposes the sensor constantly to the light projected by the lens, allowing the camera's screen to be used as an. 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 -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 — 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 or the sensor. 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 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. This is important for action or sports photography, or any other situation where the subject or the camera is moving quickly. 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 and often higher quality, offering lower noise, which is useful in low light. Although mirrorless digital cameras with APS-C and full frame sensors exist, most full frame and medium format sized image sensors are still seen in DSLR designs. For a long time, DSLRs offered faster and more responsive performance, with less , faster systems, and higher. Around 2016-17, specific 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. DSLRs typically provide the photographer with full control over all the important parameters of photography and have the option to attach additional accessories including -mounted units, for additional power and hand positions, external , 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 creative use of effects. However, small digital cameras can focus better on closer objects than typical DSLR lenses. Examples include the , which uses a Foveon X3 sensor; the ; the Canon PowerShot G1 X, which uses a 1. These premium compacts are often comparable to entry-level DSLRs in price, with the smaller size and weight being a tradeoff for the smaller sensor. 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 , some of which offer far longer focal lengths than readily available DSLR lenses. There are now available lenses for DSLR cameras, providing some of the attributes of view cameras. Nikon introduced the first PC lens, fully manual, in 1961. Recently, however, some manufacturers have introduced advanced lenses that both shift and tilt and are operated with automatic aperture control. However, since the introduction of the by Olympus and Panasonic in late 2008, are now widely available so 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 accept lenses that conform to this proprietary specification. Cameras for this system have the same sensor size as the but do not have the mirror and pentaprism, so as 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, while 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, but with an APS-C-sized sensor, was announced in January 2010: the. On 21 September 2011, announced with the a series of MILCs. A handful of also support interchangeable lenses. Six digital rangefinders exist: the APS-C-sized sensor , the APS-H-sized sensor , both smaller than 35 mm film rangefinder cameras, and the , , and 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 contamination of the sensor by dust particles when the lens is changed though recent 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 greater cost, size, and weight. They also have louder operation, due to the SLR mirror mechanism. Sony's fixed mirror design manages to avoid this problem. However, that design has the disadvantage that some of the light received from the lens is diverted by the mirror and thus the image sensor receives about 30% less light compared with other DSLR designs. Retrieved 22 August 2015. Retrieved 22 August 2015. Retrieved 22 August 2015. Archived from on May 13, 2012. Retrieved May 21, 2012. Archived from on 2010-12-28. Archived from on 2010-08-30. Archived from on 2012-01-10. SPIE 1448, Camera and Input Scanner Systems 2. SPIE 1448, Camera and Input Scanner Systems 59. Journal of The Society of Photographic Science and Technology of Japan. Archived from on 2013-05-28. Retrieved December 30, 2013. Retrieved December 31, 2013. Archived from on 2008-05-23.
