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  1. #1
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    Default Dictionar de specialitate

    dSLR :

    Digital single-lens reflex camera
    A digital single-lens reflex camera (digital SLR or DSLR) is a digital camera that operates on the same optical and mechanical principles as a modern electronic autofocus 35mm film single-lens reflex camera. The key difference is that the film is replaced with a CCD or CMOS image sensor plus accompanying electronics, thus creating images digitally in-camera, without the need to first chemically develop a latent image on film.
    SLR design
    Cross-section view of SLR system.

    The single-lens reflex (SLR) camera uses a mirror to show the image that will be captured in a viewfinder. The cross-section (side-view) of the optical components of an SLR shows how the light passes through the lens assembly (1), is reflected by the mirror (2) and is projected on the matte focusing screen (5). Via a condensing lens (6) and internal reflections in the roof pentaprism (7) the image appears in the eyepiece (. When an image is taken, the mirror moves in the direction of the arrow, the focal-plane shutter (3) opens, and the image is projected in the sensor (4) in exactly the same manner as on the focusing screen.

    Parallax-free optical viewfinder

    The principal advantage of DSLR cameras over other digital cameras is the defining characteristic of an SLR: the image in the optical viewfinder is parallax-free, because its light is routed directly from the main lens itself, rather than from an off-axis viewfinder.
    However this advantage of seeing the image exactly as it will be captured has been duplicated in many digital compact cameras in their LCD displays. The SLR still retains an advantage because the LCD images are electronically mediated and thus possess time lag, and also have relatively low resolution and brightness making it difficult to see details, especially in outdoor use. In contrast, the SLR's optical image is in real-time and is brighter and more detailed.

    Fast phase-detection autofocus

    Like most film SLRs, DSLRs typically use a phase detection autofocus system. This method of focus is very fast, and results in less focus "searching", but requires the insertion of a special sensor into the optical path, so it is usually only used in SLR designs. Compact cameras that use the main sensor to create a live preview on the LCD or electronic viewfinder need to use the slower contrast method of autofocus.

    Interchangeable lenses

    The ability to exchange lenses, to select the best lens for the current photographic need, and to allow the attachment of specialized lenses, is a key to the popularity of DSLR cameras, though not inherently unique to DSLRs. The diameters of the lenses for DSLRs are generally larger than for compact point-and-shoots, resulting in more light captured from the subject, allowing the option of using faster shutter speeds, especially in the case of low-light or moving subjects.
    In the digital era, zoom lens design is sufficiently advanced to almost eliminate most of the market for non-SLR cameras with interchangeable lenses, so digital camera lens interchangeability is, in practice, mostly restricted to the digital SLR. A non-SLR camera can have a fixed lens which will zoom from medium wide-angle to medium telephoto, omitting only fish-eye and extreme telephoto. However, there are at least four advanced digital non-SLR cameras with interchangeable lenses (see "Compacts" below).
    Most lenses intended for film can be used on DSLR cameras, but the reverse is not always true. Newer lenses may use the same style of mount as film cameras, but have newer electronics for image stabilization and image control that a film camera would not recognize. Other lenses designed for DSLR (e.g. Canon EF-S lenses) may not fit on the corresponding film or full-frame bodies; others will fit but their image circle may not cover the full film area.

    Sensor size and quality

    The Kodak SLR/c: a full-frame DSLR

    The image sensor in a DSLR is typically much larger than the one in a consumer-level, compact digital camera. A larger sensor allows better image quality, lower noise, shallower depth of field, higher sensitivity, and increased latitude and dynamic range. Many DSLR sensors are roughly APS-sized, that is, approximately 22 mm x 15 mm, a little smaller than the size of an APS-C film frame, much smaller than a frame of 135 film. A high-end compact camera like the Nikon Coolpix 8800 has an 8.8 by 6.6 mm sensor (2/3 inches format), about 4 to 6 times smaller area than a typical DSLR sensor. Lower end digital compacts have even smaller sensors. Some of the upper-end digital SLRs have sensors the same size as 35mm film, and are referred to as "full-frame" cameras.

    Depth-of-field control

    The larger size of the sensor of the DSLRs compared to compact digitals makes it much easier to limit the depth of field, for example to emphasize a face by blurring the background so that the viewer will not get distracted by the details in the background. This reduced depth of field can be a disadvantage when the photographer prefers to take pictures where as much as possible is sharply rendered.

    Angle of view

    The angle of view of a lens depends upon its focal length and the image size; a sensor smaller than 35mm film means that a lens of given focal length will have a narrower angle of view than it would on 35mm film. If the sensor is the same size as the equivalent frame of film (36 mm x 24 mm), the camera is said to have a full-frame sensor. As of 2006, only a few DSLRs have full-frame sensors (currently in production the Canon EOS-1Ds Mark II and the Canon EOS 5D). Medium-format size sensors, as used on the Mamiya ZD and other cameras, are even larger than 35mm or full-frame sensors, and capable of even greater image quality, but are much more expensive.
    The impact of sensor size on field of view is referred to as the "crop factor" or "focal length multiplier", which is a factor by which a lens focal length can be multiplied to give the full-frame-equivalent focal length for a lens. Roughly APS-sized sensors have a crop factor of 1.5 or 1.6, so a lens with a focal length of 50mm will give a field of view equal to that of a 75mm or 80mm lens on a full-frame camera. This crop makes achieving long telephoto images on an APS-sensor camera much easier than on a full-frame camera; though wide-angle views suffer by the same amount. Shallow depth-of-field images also tend to be more limited, since the wider the lens you use the more depth-of-field you get, so the smaller the sensor the more depth-of-field with the same aperture and field of view.

    Alternatives to the 35mm-based DSLR

    Depending on the position of the reflex mirror, the light from the scene can only reach either the viewfinder or the sensor. Therefore, most DSLRs don't provide "live preview" (allowing focusing, framing, and depth-of-field preview using the display). As of February 2007, there are five notable exceptions: the Canon EOS 20Da, Olympus E-330, Panasonic Lumix DMC-L1, and Leica Digilux Three, and the newly introduced Canon EOS-1D Mark III. Additionally, the Fujifilm FinePix S5 Pro offers 30 seconds of "live preview". The upcoming Olympus E-410 (June 2007) and E-510 (July 2007) will offer continuous "live preview". All of these cameras with the exception of the Canon cameras are Four Thirds System cameras.
    Many medium format roll-film SLRs can accept a digital camera back to turn the camera into a DSLR with very high image resolution and quality (typically 22-39 megapixels as of January 2007). However, the combination is very expensive and bulky, and more suited to still life than to action photography.


    At Photokina in 1986, Nikon revealed a prototype analog electronic still SLR camera, the Nikon SVC, a precursor to the digital SLR [1]. The prototype body shared many features with the N8008.[1]
    In 1991 Kodak released the first commercially available digital SLR, the Kodak DCS-100. It consisted of a modified Nikon F3 SLR body, modified drive unit, and an external storage unit connected via cable. The camera was capable of producing 1.3 megapixel (1280x1024) images and cost approximately US$30,000. This was followed by the Kodak DCS-200 with integrated storage.[2]
    Over the next decade, digital SLRs have been released by various companies such as Canon, Nikon, Kodak, Pentax, Olympus, Panasonic, Samsung, Konica Minolta, Fujifilm, and Sigma with higher resolution and lower prices.
    In January 2000 Fujifilm announced the FinePix S1 Pro which was the first DSLR that had a 'reasonable' price and was marketed to non-professionals.
    In 2003 Canon introduced the 6.3 megapixel EOS 300D SLR camera (known in the United States as the Digital Rebel) at an MSRP of under US$1000. Its popularity, especially among newspaper and amateur photographers, encouraged other manufacturers to produce affordable digital SLR cameras, significantly lowering entry costs and allowing more casual photographers an opportunity to experience the digital SLR photography. Canon introduced the next generation 8 megapixel EOS 350D (Digital Rebel XT) in 2005, then followed that with the 10 megapixel EOS 400D (Digital Rebel XTi) in 2006.
    In February 2004 Kodak released two 14-megapixel full-frame (24x36mm) DSLRs named Kodak DCS 14 N ,Kodac DSC 14 C, one for Nikon lens mount and one for Canon lens mount. Kodak has since discontinued them. Konica Minolta briefly produced two DSLR models, the 5D and 7D, but has sold their digital camera business to Sony which revamped the range through its α (alpha) brand. At one time, Kyocera also manufactured DSLRs and marketed them under the Contax name,[3] but in 2005 withdrew from the DSLR camera field. Sigma Corporation of Japan produced the Sigma SD9 and Sigma SD10 DSLR cameras with the Foveon X3 sensor, but those cameras are no longer in production; the successor to this line, the Sigma SD14, was announced at Photokina in 2006.
    Canon, Nikon, Pentax, Olympus, Sony and Fujifilm currently have DSLR models in production.

    Present day

    Canon and Nikon currently have the largest range of amateur and professional DSLR cameras. Canon's line includes the 400D, 350D, 30D, 5D, 1D Mk. IIn, 1Ds Mk. II, and the Canon EOS-1D Mark III, all of which have CMOS sensors. Nikon also has a broad line of DSLRs which includes the D40, D40x, D50, D70s, D80, D200, D2Hs and D2Xs. Fujifilm sells Nikon-lens compatible DSLR cameras, the FinePix S3 Pro and FinePix S5 Pro. Olympus, together with Panasonic and Leica, make DSLR cameras that conform to the Four Thirds System, including several models that feature a live preview LCD in addition to the viewfinder. Sigma produces an innovative DSLR with the multi-layered Foveon X3 sensor to deliver excellent color and detail, while Pentax also has digital SLRs that use their lenses and accessories. Hasselblad and Mamiya produce medium-format DSLRs which produce the highest quality digital images. Their larger sensors are able to capture much more detail than the 35mm full-frame and smaller sensors found on the Canon, Nikon, Olympus, Pentax, and Sigma models.

    Digital SLR versus SLR-like and compact cameras

    Non-SLR digital cameras are of two types: SLR-like prosumer digital cameras (also called advanced digital cameras) and compact digital cameras. Both have permanently fixed lenses.

    SLR-like cameras

    The "SLR-like" or "advanced" cameras (e.g. some Nikon Coolpix models, the Sony DSC V, Sony DSC H and Sony DSC R series, the Panasonic FZ series, the Canon PowerShot A, G, S and Pro models, Minolta DiMAGE series (DiMAGE 7, 7Hi, A1, A2, A200) and several Fujifilm FinePix models) offer through-the-lens (TTL) viewing through the focusing lens, projected onto its viewfinder as well as a LCD screen, through an EVF (electronic viewfinder). The difference compared to a DSLR is that the viewfinder shows a digitally created copy of the TTL image, whereas the viewfinder in a DSLR shows the actual optical TTL image via its mirror. An EVF image reacts more slowly 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. The limitation of a prosumer digital camera is its fixed lens, typically limited to about a 12:1 focal-length range. The fixed lens also minimizes the risk of getting dust on the sensor.
    Several of the high-end prosumer cameras have a movable LCD screen (e.g. Canon PowerShot Pro1 and Konica Minolta A200), which can be used instead of the regular viewfinder in difficult angles, enabling the photographer to look through the lens even when standing above or below the camera. The LCD screen also enables the photographer to look at the stored pictures in a convenient way.
    High-end prosumer cameras such as the Konica Minolta A200 provide image stabilization via CCD sensor shift; this stabilization can reduce the blurring effect of camera shake.


    The compact digital cameras, commonly referred to as 'point-and-shoot' cameras because of their ease of use, can usually be operated at arm's length using only the LCD display screen at the rear of the camera, and most models also have simple optical viewfinders like traditional compact film cameras. Like the SLR-like prosumer cameras, nearly all compacts have no ability to accept interchangeable lenses, with the exception of the Epson R-D1 and the Leica M8.
    Most compacts are therefore provided with a zoom lens that covers the most commonly used fields of view. Compacts may be altered through the use of supplementary add-on lens converters to provide an added telephoto or wide angle field of view, though the image quality is usually affected to a significant degree. Most compacts are significantly slower in image capture (time from shutter release to storage) than DSLR cameras, a disadvantage for action, wildlife, and sports photography. Their zoom lenses can frequently have a much slower (smaller) effective wide-open aperture (f-number) than DSLR or prosumer cameras, especially at the telephoto end, which further limits their utility in situations involving low light levels and moving subjects. Image stabilization is a feature available in some compact cameras that can effectively remedy the issue of camera-shake in low-light conditions without moving subjects and therefore reduce blurring in low-light photographs.

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    SLR :

    Single-lens reflex camera

    The single-lens reflex (SLR) is a type of camera that uses a movable mirror placed between the lens and the film to project the image seen through the lens to a matte focusing screen. Most SLRs use a roof pentaprism or pentamirror to observe the image via an eyepiece, but there are also other finder arrangements, such as the waist-level finder or porro prism.
    The shutter in almost all contemporary SLRs sits just in front of the focal plane (and is called a focal plane shutter). If it does not, some other mechanism is required to ensure that no light reaches the film between exposures. For example, the Hasselblad 500C camera uses an auxiliary shutter blind in addition to its in-lens leaf shutter.

    Cross-section view of SLR system:
    1) Lens
    2) Mirror
    3) Shutter
    4) Film or sensor
    5) Focusing screen
    6) Condensing lens
    7) Pentaprism

    The cross-section (side-view) of the optical components of a typical SLR camera shows how the light passes through the lens assembly (1), is reflected by the mirror (2) and is projected on the matte focusing screen (5). Via a condensing lens (6) and internal reflections in the roof pentaprism (7) the image appears in the eyepiece (. When an image is taken, the mirror moves in the direction of the arrow, the focal plane shutter (3) opens, and the image is projected onto the film or sensor (4) in exactly the same manner as on the focusing screen.
    This feature distinguishes SLRs from other cameras, as the photographer sees the image composed exactly as it will be captured on the film or sensor (see Advantages below).
    Since the technology became widespread in the 1970s, SLRs have become the main type of camera used by dedicated amateur photographers and professionals, though some landscape photographers may prefer view cameras.


    Large format SLR cameras were probably first sold in 1884.[1] The Ihagee Kine-Exakta was the first 35 mm SLR and it was truly influential. Further Exakta models, all with waist-level finders, were produced up to and during World War II. Another ancestor of the modern SLR camera was the Swiss-made Alpa, which was innovative, and proved influential for the later Japanese cameras. The first solution for an eye-level viewfinder was patented in Hungary on August 23, 1943, by Jenő Dulovits, who then designed the first 35mm camera that had one implemented: the Duflex, which used a system of mirrors to provide a laterally correct, upright image in the eye-level viewfinder. The Duflex, which went into serial production in 1948, was also the world's first SLR with an instant-return (a.k.a. autoreturn) mirror.
    The first serially produced SLR that employed a roof pentaprism was the East German Contax S, announced on May 20, 1949.
    The Japanese further developed the SLR. In 1952, Asahi developed the Asahiflex and in 1954, the Asahiflex IIB. In 1957, the Asahi Pentax combined the fixed pentaprism and the right-hand thumb wind lever. Nikon, Canon and Yashica introduced their first SLRs in 1959 (the F, Canonflex, and Pentamatic, respectively).
    Through-the-lens (TTL) light metering came to the SLR in the early 1960s, with 1962's Topcon RE Super (spot metering) and 1964's Pentax Spotmatic (center-weighted average metering). Auto-exposure was next, introduced by the Savoyflex and popularized by Konishiroku in 1965's Konica Auto-Reflex and its successors. Full-program auto-exposure soon followed. The 1970s and 1980s saw steadily increasing use of electronics, automation, and miniaturization, including integrated motor driven film advance with the Konica FS-1 in 1979, and motor rewind functions.

    Two Classic 35mm SLR cameras: Canon AE-1 & Minolta X-700


    The revolutionary Nikon F


    The first phase detection SIR TTL autofocus SLR was 1981's Pentax ME-F.[2] The Minolta Maxxum 7000, released in 1985, was the first SLR with integrated motorised autofocus and film advance winder—which became the standard configuration for SLR cameras from then on. This had significant impact on the industry. Some manufacturers discarded their existing systems to enter the AF era, while others chose to adapt their systems for compatibility.
    From the late 1980s competition and technical innovations made the camera systems more "intelligent" by adding more advanced light metering, and by allowing the different components to exchange information electronically. The user interface also changed on many cameras, replacing needle display and light-emitting diodes (LEDs) with more comprehensive liquid crystal displays (LCDs) both in viewfinder and externally on the cameras. Wheels and buttons replaced the shutter dial on the camera and the aperture ring on the lens on many models. Some manufacturers also introduced antishake features on some lenses to allow for longer exposure times without a tripod.

    Digital SLRs

    Canon, Nikon, Samsung, Pentax, Minolta, and Sony have developed digital SLR cameras compatible with their film SLR systems (though Konica-Minolta recently sold its SLR camera division to Sony who will continue manufacturing), while Olympus introduced the new digital-only Four Thirds SLR system, adopted later by Panasonic and Leica.


    SLR cameras have been produced for most film formats as well as digital formats. Most film SLRs use the 35 mm format, as this offers a good compromise of image quality, size, and cost. Medium format SLRs give a higher quality image when this is required. Digital SLRs (dSLRs) appeared on the market in the late 1990s and as of 2006 are used by many professional photographers as well as amateur enthusiasts. Early SLRs were built for large format photography, but this has largely died out. A small number of SLRs were built for APS but this did not prove popular. SLRs were even built for film formats as small as 110, e.g. the Pentax Auto 110.

    Common features

    Other features found on many SLR cameras include through-the-lens (TTL) metering and sophisticated flash control. Many models on the market today actually measure the light that bounces off the film, and close the shutter when the picture has had enough exposure.
    Likewise, they can send out several short bursts of flash, determine the amount that comes back from the scene, then send out just the right amount of energy for a perfectly exposed photograph. Sophisticated cameras can even make it easy for the photographer to balance flash and available light for the desired look. While these capabilities are hardly unique to the SLR, manufacturers included them early on in the top models, whereas the best rangefinder cameras adopted such features later.

    Cut-away of a classic Minolta SLR


    Many of the advantages of SLR cameras derive from viewing the scene through the taking lens. Most other types of camera do not have this function; subjects are seen through a viewfinder that is near the lens, making the photographer's view different from that of the lens. SLR cameras provide photographers with precision and confidence; they are seeing an image that will be exposed onto the negative exactly as it is seen through the lens. There is no parallax error, and exact focus can be confirmed by eye — otherwise hard for macro photography and when using telephoto lenses. The true depth of field may be seen by stopping down to the taking aperture, possible on all but the cheapest cameras. Because of the SLR's versatility, most manufacturers have a vast range of lenses and accessories available.
    Compared to most fixed-lens compact cameras, the most commonly used and cheapest SLR lenses offer a wider aperture range and larger maximum aperture (typically f/1.4 to f/1.8 for a 50 mm lens). This allows photographs to be taken in lower light conditions without flash, and allows a narrower depth of field, which is useful for blurring the background behind the subject, making the subject more prominent. This is commonly used in portrait photography.
    The variety of lenses also allows for the camera to be used in very different situations. This gives the photographer considerably more control over how the picture is framed than a simple view camera. In addition, SLR lenses can also be found with extremely long focal lengths, letting a photographer be far away from the subject. This is particularly useful if the subject is dangerous (e.g., wildlife), or the subject would prefer the photographer to stay away (e.g., a celebrity).


    Single-lens reflex cameras cannot be made as small or light as other camera designs — such as rangefinder cameras, autofocus compact cameras and digital cameras with electronic viewfinders (EVF) — owing to the mirror box and pentaprism/pentamirror. The mirror box also prevents lenses from having rear elements closer to the film or sensor; this means that simple designs for wide angle lenses cannot be used. Instead, poorer-performing, larger and more complex retrofocus designs are required.
    The SLR mirror blacks out the viewfinder when the picture is taken. In addition, moving the mirror takes time, limiting the maximum shooting speed; the mirror also causes noise and vibration. Partially-reflective (pellicle) fixed mirrors avoid these problems and have been used in a very few designs including the Canon Pellix, but these reduce the light getting to the film or sensor. To avoid the noise and vibration, many professional cameras offer a mirror lock-up feature, but this blacks out the viewfinder totally when in use.
    Most digital SLRs in general cannot display a live view on their rear LCD displays, unlike compact or bridge cameras, and must be held to the eye to compose the picture (with the exception of the Olympus E-330, the Panasonic DMC-L1, Leica Digilux 3 and the Canon EOS-1D Mark III). Movie modes are also unavailable.[3] Electronic viewfinders have the potential to give the advantage of a digital SLR (through-the-lens viewing) without many of the disadvantages, but as of 2006 sensor and display technology is insufficient for wide acceptance among the advanced amateur or professional markets that buy digital SLRs.
    The price of SLRs in general also tends to be higher than that of other types of cameras, owing to the internal complexity. This is only aggravated by the expense of additional components, such as a flash attachment or various types of lenses. Typically the initial investment in equipment is prohibitive enough to keep the casual photographer away from SLRs.[citation needed]
    There is also the obvious problem of a higher rate of breakdowns than a simpler camera of the same build quality. However since SLRs are not aimed at casual users they tend to be built to much higher standard than other camera types making their reliability in practice higher.[citation needed] Because many SLRs have interchangeable lenses, there is a tendency for dust, sand and dirt to get into the main body of the camera, dirtying or even jamming the mirror's movement. In addition, these particles can also jam or otherwise hinder the focusing feature of a lens. This problem has been somewhat reduced in DSLRs as some cameras have a built-in sensor cleaning unit.

    SLR chronology
    • 18th century: SLR camera obscuras popular as drawing aids. Artist can trace over the ground glass image to produce a true-life realistic picture.
    • 1861: Thomas Sutton (UK) received first patent for SLR photographic camera. An unknown number made but very few; no known production model; no known surviving examples. The manually levered reflex mirror also served as the camera's shutter. Used glass plates.
    • 1884: Calvin Rae Smith Monocular Duplex (USA): first known production SLR. Used glass plates (original model 3Ľ×4Ľ inch, later 4×5 inch); many were adapted to use Eastman sheet film. Large-format glass plate or sheet film SLRs were the dominant SLR type until circa 1915. However, SLRs themselves were not commonplace until the 1930s.
    • 1900: J.F. Shew & Co Delta Reflex Camera (UK): first focal plane shutter SLR. Used 3Ľ×4Ľ inch plates and had cloth focal plane shutter with speeds to 1/1000th second.
    • 1907: Folmer & Schwing Graflex No. 1A (USA): first medium format roll film SLR. Took eight exposures of 2˝×4˝ inch frames on 116 roll film. Had folding waist level finder and focal plane shutter. Roll film (usually 120 type) SLRs became the dominant SLR type in 1930s.
    • 1925: Ernemann (merged into Zeiss Ikon, 1926) Ermanox Reflex (Germany): first SLR with high speed lens (10.5 cm f/1.8 or 85 mm f/1.8 Ernostar). Established SLR as viable photojournalist's available-light camera. Had folding waist level finder and focal plane shutter. Used 4.5×6 cm glass plates or sheet film; adaptable to roll film.
    • 1933: Ihagee VP Exakta (Germany): first 127 roll film SLR. First camera with internal flash synchronization. Took eight exposures of 4.5×6 cm frames on 127 roll film. Had folding waist level finder and focal plane shutter. Established standard body shape and handling soon to be standard in 35 mm SLRs except that Exakta SLRs had primarily left-handed controls and were more trapezoidal shaped than rectangular.
    • 1935: 135 film, commonly called 35 mm film, introduced by Kodak (USA). Was (and is) 35 mm nominal width (1⅜ inch actual width), acetate base, double perforated film, pre-loaded into felt-lipped, daylight-loading cartridges ready-to-use for still cameras. Originally intended for Kodak Retina, Zeiss Ikon Contax and E. Leitz Leica 35 mm rangefinder cameras. Previously, bulk rolls of 35 mm motion picture film would need to be user cut and loaded, in complete darkness, into camera specific cartridges or magazines. The September 1936 release of Kodachrome (the first high speed (ISO 8 equivalent), realistic color film) in standardized 135 format (but not medium format roll film) spurred explosive growth in the popularity of all types of miniature format 35 mm cameras. The vast majority were not high-end SLRs or RFs, but basic amateur RFs such as the multi-million selling Argus C3 (USA) of 1939. Originally, each US$3.50 (including processing) Kodachrome cartridge gave eighteen exposures if the camera used the 24×36 mm frame size (double the frame size of 35 mm cine cameras) established by the Multi-Speed Shutter Co. Simplex (USA) camera of 1914 and popularized by the E. Leitz Leica A (Germany) of 1925. The 24×36 mm frame size did not become the universal standard frame size until the early 1950s. Note that 135 film cameras using non-standard frame sizes, such as 24×18 mm or 24×24 mm, continued to the made until at least 1990.
    • 1935: Possible date of emergence of the Gomz Sport (Спорт), from the Soviet Union; if so, this was the first 35 mm SLR.
    • 1936: Ihagee Kine Exakta (Germany): probable first 35 mm SLR. First system SLR, first bayonet lens mount. Had left-handed shutter release and rapid film wind thumb lever, folding waist level finder and 12 to 1/1000th second focal plane shutter. Well integrated design with excellent interchangeable lenses and good accessory system. Fewer than 30,000 Kine Exaktas were made before World War 2 stopped production in 1940. Production of improved models re-started after the war and Exakta was the best known 35 mm SLR brand until 1959.
    • 1947: Gamma Duflex (Hungary): first instant return mirror SLR. Had a mirror prism finder, an intermediate step to solid pentaprism. Reflex mirrors coupled to the shutter release had been spring actuated to rise automatically since the 19th century, but the viewfinder would remain blacked-out until the mirror was manually cocked back down. With an automatic, instant return mirror, the viewfinder blackout time might be as short as ⅛th second.
    • 1948: Hasselblad 1600F (Sweden): first 2Ľ medium format system SLR suitable for professional use. Took twelve exposures of 2Ľ×2Ľ inch (6×6 cm) nominal frames (56×56 mm actual frames) on 120 film. Had modular design accepting interchangeable lenses, film magazines and folding waist level finder. The 1/1600th second corrugated stainless steel focal plane shutter was unreliable and was replaced by a slower but more reliable 1/1000th focal plane shutter in the Hasselblad 1000F (Sweden) of 1952.
    • 1948: Alpa Prisma Reflex (Switzerland) had a pentaprism viewfinder in 1948, but its eyepiece was angled upward at 45ş.
    • 1949: VEB Zeiss Ikon (Dresden) Contax S (East Germany): first pentaprism eyelevel viewing 35 mm SLR. (The Italian Rectaflex Standard came very soon after.) First M42 screw mount camera. (The East German KW Praktica came out at about the same time.) With earlier "waist level" SLR viewfinder systems (in which the photographer looks downward at the reflex mirror's image on the focusing screen), moving subjects are seen to track across the field-of-view in reverse direction of their actual motion, making action shooting counter-intuitive. A pentaprism is a five-sided chunk of glass silvered on two sides that collects, redirects and re-reverses the light from the mirror with minimal light loss. With a proper pentaprism, all a photographer needs to do is hold the camera up to eyelevel and everything is there. The pentaprism SLR had first been proposed in the 19th century and was used in non-35 mm SLRs in the 1930s. Similar systems (or, in the 1990s, its cheaper alternative, the pentamirror) became so common in 35 mm SLRs by the late 1950s that it is the characteristic pentaprism "head" atop the camera body that defines the type for most people.
    • 1950: Ihagee Exakta Varex V (East Germany; called V within USA): first interchangeable viewfinder, first interchangeable focusing screens, first viewfinder condenser lens SLR.
    va urma

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    continuare :

    • 1950: Angénieux 35mm f/2.5 Retrofocus Type R 1 (France): first retrofocus wide angle lens for 35 mm SLRs. Regular wide angle lenses (meaning short focal length lenses) need to be mounted close to the film. However, SLRs require that lenses be mounted far enough in front of the film to provide space for the movement of the mirror - the "mirror box." Therefore, the focal length of early 35 mm SLR lenses was no less than about 40 mm. This prompted the development of wide lenses with more complex retrofocus optical designs. These use very large negative front elements to force back focus distances long enough to ensure clearance.
    • 1951: Zenit (Soviet Union, Russia; Зенит): first Russian pentaprism eyelevel viewing 35 mm SLR.
    • 1951: Asahiflex I (Japan): first Japanese 35 mm SLR. Had folding waist level finder and focal plane shutter.
    • 1953: Zeiss Ikon Contaflex I (West Germany): first leaf shutter 35 mm SLR. Had Synchro-Compur leaf shutter and fixed 45 mm f/2.8 Tessar lens. For many years, reliable focal plane shutters were very expensive and SLRs equipped with Compur or Prontor leaf shutters were strong competitors. As focal plane shutters improved, their faster available speeds won out and leaf shutter 35 mm SLRs disappeared around 1973.
    • 1954: Asahiflex IIB (Japan; called Sears Tower 22 in USA): first SLR with reliable instant return mirror.
    • 1954: Praktina FX (East Germany): first available spring powered motor drive for SLR, first breech-lock lens mount.
    • 1956: Kodak Retina Reflex (USA/Germany): first interchangeable lens, leaf shutter 35 mm SLR. Accepted excellent Kodak Retina leaf shutter 35 mm rangefinder interchangeable lenses.
    • 1957: Asahi Pentax (Japan; called Sears Tower 26 in USA): first SLR with right-handed rapid-wind thumb lever, first fold-out film rewind crank, first microprism focusing aid. First Asahi SLR with M42 screw mount. Well integrated focal plane shutter, instant return mirror and pentaprism design.
    • 1957: Hasselblad 500C (Sweden): replacement of 1600F/1000F's problematic focal plane shutter with reliable interlens Synchro-Compur leaf shutter made the 2Ľ medium format SLR the dominant professional studio camera by the late 1950s. Well integrated, durable and reliable design with excellent auto-diaphragm interchangeable lenses and large accessory system.
    • 1958: Zunow SLR (Japan): first internal auto-diaphragm (Zunow-matic Diaphragm System) 35 mm SLR and lenses. Well integrated focal plane shutter, instant return mirror, pentaprism and auto-diaphragm design with excellent lenses and good accessory system. Stopping down the lens aperture to prepare for exposure transmits less light to the mirror and the viewfinder may become very dim - perhaps even too dark to see the image. Auto-diaphragms coupled to the shutter release that automatically stop down when the mirror swings up and reopen when the mirror comes down provides almost continuous fully open aperture viewing. Auto-diaphragm lenses and instant return mirror, focal plane shutter SLRs require precise camera-to-lens linkage, but can choreograph the entire shutter-button release, raise mirror, close lens, open shutter, close shutter, open lens, lower mirror exposure sequence in as little as ⅛th second. Originally, these were mechanical spring/gear/lever systems energized concurrent with manually winding the film, but modern systems are electronically timed and electromagnetically powered. The financially weak Zunow company was unable to capitalize on its design; few examples of the camera (and much fewer of the wide and tele lenses for it) were produced before the company switched back to lenses for other companies' cameras.
    • 1959: Nikon F (Japan): first pro caliber 35 mm system SLR, first electric motor drive for SLR. (The Japanese Nikon S2 35 mm rangefinder camera had first electric motor drive for any camera type in 1954.) Well integrated, durable and reliable focal plane shutter, instant return mirror, pentaprism and auto-diaphragm design with excellent interchangeable lenses and huge accessory system. Although the F was not technologically ground-breaking, it sold nearly one million units and made the 35 mm SLR the dominant professional miniature format camera (displacing the 35 mm RF) by the early 1960s. The perfection of the optical and mechanical formulae of the interchangeable lens SLR in the one-two punch of the Hasselblad 500C (see above) and Nikon F also ended the popularity of the medium format twin-lens reflex (TLR) camera (typified by the Franke & Heidecke Rolleiflex/Rolleicord series (Germany, later West Germany)) by the early 1960s. The F's improved successor, the Nikon F2 (Japan) of 1971, is widely regarded as the finest mechanically controlled 35 mm SLR camera ever made.
    • 1959: Voigtländer–Zoomar 1:2.8 f=36mm–86mm (USA/West Germany): first zoom lens for 35 mm still cameras. Originally mounted for Voigtländer Bessamatic series (West Germany) 35 mm leaf shutter SLRs, but later available in Exakta and other mounts.
    • 1960: Royer Savoyflex Automatique (France): first autoexposure SLR. Had unreliable mechanical autoexposure system controlled by external selenium light meter, Prontor leaf shutter and fixed 50 mm f/2.8 Som-Berthiot lens. The first autoexposure still camera was the non-SLR Kodak Super Kodak Six-20 (USA) of 1938 with a mechanical system controlling both aperture and shutter speed via trapped-needle method coupled to external selenium photoelectric cell.
    • 1960: Krasnogorsky zavod (KMZ) Narciss (Soviet Union, Russia; Нарцисс): first subminiature SLR. Took 14×21 mm frames on unperforated, specially spooled 16 mm film. Compact design with interchangeable lenses and removable finder. Submini film format cameras (those using smaller than 135 film) have always been unpopular with serious photographers because the very high level of enlargement needed to make even small 3˝×5 inch prints from such tiny negatives can magnify normally minor image limitations unless using the highest quality cameras, lenses and films.
    • 1962: Nikkorex Zoom 35 (Japan): first 35 mm SLR with fixed zoom lens (Zoom-Nikkor Auto 43–86 mm f/3.5). Had non-pentaprism, four mirror reflex viewfinder and leaf shutter.
    • 1963: Olympus Pen F (Japan): first single frame (also called half frame) 35 mm SLR, porroprism SLR. Took up to 72 exposures of vertical 18×24 mm frames on 135 film. Had flat-topped non-pentaprism porroprism reflex and optical relay viewfinder, and rotary focal plane shutter. Well integrated compact design with excellent interchangeable lenses and large accessory system. The original non-SLR Olympus Pen (Japan) of 1960 helped give 35 mm still cameras that used the standard motion picture frame size of 35 mm film a burst of popularity. It ended by the late 1960s. Although single frame cameras used standard 135 film, single frame photofinishing was always special-order. Kyocera/Yashica unsuccessfully attempted to revive the format as "Double 35" with their Yashica Samurai series (Japan) SLRs in 1988.
    • 1963: Topcon RE Super (Japan; called Super D in USA): first SLR with through-the-lens (TTL) light meter for convenient exposure control. Had internal CdS cell, match-needle, open aperture metering with auto-diaphragm lenses. Film is rated at a particular "speed" sensitivity. It needs a specific amount of light to form an image. Originally separate selenium photoelectric devices to sense the ambient light, miniature cadmium sulfide (CdS) light meters built into the camera that gave TTL light exposure readings were a great leap forward in convenience that became normal in virtually all 35 mm SLRs by the late 1960s.
    • 1964: Asahi (Honeywell in USA) Pentax Spotmatic (Japan): second SLR with TTL metering (stop-down aperture, full area averaging). Well integrated, compact and reliable focal plane shutter, instant return mirror and pentaprism design with excellent non-auto-diaphragm interchangeable lenses. The Spotmatic (and rival TTL metering SLRs, including the Canon FT (1966; stop-down aperture, partial area), Minolta SRT101 (1966; open aperture, modified centerweighted) and Nikkormat FTN (1967; open aperture, centerweighted), all from Japan) made the Japanese 35 mm SLR the dominant advanced amateur camera by the late 1960s.
    • 1964: Krasnogorsky zavod (KMZ) Zenit-5 (Soviet Union, Russia; Зенит-5): first SLR with built-in electric motor drive.
    • 1965: Canon Pellix (Japan): first pellicle reflex mirror SLR. Virtually all SLRs use fast moving reflex mirrors that swivel out of the way to take the picture, causing mirror shock vibration, blacking-out the viewfinder and delaying shutter firing. Camera shake can blur the image and the subject (which might have moved) cannot be seen at the instant of exposure. A fixed semi-transparent pellicle reflex mirror, reflecting 30% of the light to the viewfinder and transmitting 70% to the film, prevents camera shake and viewfinder blackout, and reduces shutter lag time at the costs of a dimmer viewfinder image, longer exposure times and possible image quality loss. Modern instant return mirrors are fast enough and have efficient enough shock damping systems that the trade offs are not usually considered worthwhile. Pellicle mirror SLRs are very rare and are usually specialized designs for ultra-high speed (10+ frames per second) sequence shooting.
    • 1966: Konica Autorex (Japan; called AutoReflex in USA): first SLR with successful shutter-priority (first with focal plane shutter) autoexposure. Most unusually, it allowed selection between frame sizes (horizontal 24×36 mm or vertical 18×24 mm) between frames on the same roll of film. Used mechanical trap-needle autoexposure system controlled by external CdS meter.
    • 1967: Zeiss Ikon Contarex Electronic (West Germany): first SLR with electronically controlled focal plane shutter. Had interchangeable film backs, a feature common with medium format SLRs and used in 35mm rangefinder cameras, but unique to Contarex/Contaflex series among 35 mm SLRs. Although Contarex SLRs and their Zeiss lenses were of extremely high quality, they were also extremely expensive and of idiosyncratic (even clumsy) handling.
    • 1968: Konica Autoreflex T (Japan): first SLR with internal open aperture TTL metering autoexposure (mechanical shutter-priority).
    • 1968: Kodak Instamatic Reflex (USA/Germany): first Kodapak 126 Instamatic film SLR, first camera with electronically controlled autoexposure. Took 26.5×26.5 mm frames on paper-backed, singly-perforated, 35 mm wide film pre-threaded into double-ended cartridge with film supply and take-up spool. Was leaf shutter design with autoexposure system coupled to external metering cell. Accepted excellent Kodak Retina Reflex 35 mm leaf shutter SLR interchangeable lenses. Drop-in loading 126 film was introduced in 1963 as Kodak's first attempt (of many) to solve the problem of amateurs' difficulty in loading 135 film manually. It was briefly an extremely popular amateur non-SLR format, but almost dead by 1972.
    • 1970: Minolta SPM (Japan): first Japanese SLR with built-in electric motor drive.
    • 1970: Yashica TL-Electro X (Japan): first SLR with all solid-state electronic light metering system.
    • 1970: Mamiya RB 67 (Japan): first 67 medium format system SLR. Took ten exposures of 2Ľ×2ľ inch (6×7 cm) nominal frames (56×69.5 mm actual frames) on 120 film.
    • 1970: Mamiya M645 (Japan): first 645 medium format system SLR. Took fifteen exposures of 2Ľ×1⅝ inch (6×4.5 cm) nominal frames (56×41.5 mm actual frames) on 120 film.
    • 1971: Asahi SMC Takumar lenses (Japan): first multicoated (Super-Multi-Coated) lenses for consumer cameras; for M42 screw mount Asahi Pentax SLRs. Lenses with glass elements "single-coated" with a very thin layer of magnesium or calcium fluoride to suppress flare producing surface reflections became common for high-end cameras by 1960. Coating lenses with up to a dozen different layers of chemicals to suppress reflections across the visual spectrum (instead of at only one compromise wavelength) was a logical progression.
    • 1971: Asahi Pentax Electro Spotmatic (Japan; called Honeywell Pentax ES in USA): first SLR with electronic aperture-priority (using stop-down TTL metering) autoexposure plus electronically controlled shutter. Earlier mechanical AE systems tended to be unreliable, but reliable and convenient AE systems (as well as other electronic control systems) that electronically set either the camera shutter speed or lens aperture from light meter readings once the other was manually set began with the Electro Spotmatic. Rival electronic AE SLRs included the Canon EF (1973; shutter priority), Minolta XE–7 (1972; aperture priority) and Nikkormat EL (1972; aperture priority), all from Japan. Electronic AE came to most 35 mm SLRs by the late 1970s. The electronic AE SLR also killed the German camera industry when the Germans failed to keep up with the Japanese. After ailing throughout the 1960s, such famous nameplates as Contax, Exakta, Leica, Rollei and Voigtländer went bankrupt, were sold off, contracted production to East Asia or became boutique brands in the 1970s.
    • 1971: Praktica LLC (East Germany): first interchangeable lens camera with electric contact lens mount, first camera with electric lens diaphragm stopdown control. Had M42 screw mount modified for open aperture metering. The M42 mount was a very popular interchangeable lens mount for a quarter century. It was used by almost two dozen different SLR brands, most notably Asahi Pentax. (Asahi became so closely associated with it that it was often erroneously called the Pentax screw mount.) However, by the early 1970s, the M42's limitations, especially no provision for auto-diaphragm lens open aperture viewing and metering, were becoming serious liabilities. After unpopular and uncoordinated attempts to modify the screw mount to support auto-diaphragm lenses, Asahi abandoned the M42 mount in 1975, effectively killing it.
    • 1972: Polaroid SX-70 (USA): first instant film SLR. Had non-pentaprism mirror reflex system and electronic autoexposure in flat-folding body with bellows and fixed 116 mm f/8 lens. Took ten exposure, 3⅛×3⅛ inch frame Polaroid SX-70 instant film packs. The principle of self-developing "instant photography" came to Edwin Land in 1943. The first production instant camera was the non-SLR Polaroid Land Model 95 (USA) of 1948, producing sepia-toned, peel-apart pictures. Steady improvements culminated in SX-70 type full-color, self-contained, develop-before-your-eyes, "garbage-free" prints.
    • 1972: Olympus OM-1 (quickly changed from M-1 when E. Leitz objected; Japan): first compact 35 mm SLR. At 510g, about two thirds the weight of most earlier 35 mm SLRs. Excellent mechanical design with excellent interchangeable lenses and large accessory system.
    • 1974: Vivitar Series 1 70–210mm f/3.5 (USA/Japan): first professional-level quality macro zoom lens for 35 mm SLRs. Early zoom lenses often had very inferior optical quality compared to prime lenses, but improvements in zoom lens design and construction made zooms normal on virtually all but the most expensive still cameras by 1990.
    • 1976: Minolta XD11 (Japan; called XD7 in Europe, XD in Japan): first dual mode autoexposure SLR. Had both aperture-priority and shutter-priority autoexposure.
    • 1976: Canon AE-1 (Japan): first SLR with microprocessor electronics. Well integrated and compact shutter-priority autoexposure design with excellent interchangeable lenses and large accessory system. Sold five million units and immediately made the 35 mm SLR a popular amateur camera.
    • 1976: Olympus OM-2 (Japan): first SLR with TTL, off-the-film (OTF) flash autoexposure. Manual flash exposure control for a natural look is complex and convenient TTL autoflash metering became standard in virtually all SLRs by the mid 1980s.
    • 1976 Minolta 110 Zoom SLR (Japan): first Pocket Instamatic 110 film SLR. Had built-in zoom lens (fixed 25–50 mm f/4.5 Zoom Rokkor). Took up to 24 exposures of 13×17 mm frames on paper-backed, singly-perforated, 16 mm wide film pre-threaded into double-ended cartridge with film supply and take-up spool. Compact, drop-in loading 110 film was introduced by Kodak in 1972. It was briefly an extremely popular amateur non-SLR format but almost dead by 1982.
    • 1978: Polaroid SX-70 Sonar (USA): first electronic autofocus SLR. Had active ultrasonic sonar rangefinder AF system. This unique-to-Polaroid AF system had no influence on any other type of AF SLR. Took ten exposure, 3⅛×3⅛ inch frame, Polaroid Time-Zero SX-70 instant film packs.
    • 1978: Konica FS-1 (Japan): first SLR with built-in motorized autoloading. Also had autowinding, but not auto-rewind. A great photographer's dislike (and Kodak bugbear) of 135 film was the need to manually thread the film leader into the camera's take-up spool and built-in, motorized, automatic film-handling systems became normal in virtually all 35 mm SLRs by late 1980s. This is, of course, a non-issue in modern digital SLRs.
    • 1978: Asahi Pentax Auto 110 (Japan): first interchangeable lens Pocket Instamatic 110 film system SLR. Mini-35mm SLR-like autoexposure design with good interchangeable lenses and large accessory system. Was smallest and lightest SLR ever made – 2.2×3.9×1.8 inch, 5.6 ounce with Pentax-110 24 mm f/2.8 lens.
    • 1978: Canon A-1 (Japan): first camera with an electronically controlled programmed autoexposure mode. Instead of the photographer picking a shutter speed to freeze or blur motion and choosing a lens aperture f-stop to control depth of field (focus), the A-1 had a microprocessor computer programmed to automatically select a compromise exposure from light meter input. Virtually all cameras had some sort of program mode or modes by the mid-1980s. It was also the first camera to have all four of the now standard PASM (program/aperture-priority/shutter-priority/manual) exposure modes. Canon's long term emphasis on the highest possible technology eventually allowed the company to dominate the 35 mm SLR market; first at the amateur level, with their AE-1 (see above) and A-1, and then (despite a stumble in the mid 1980s when they came late to autofocus) the professional level in the early 1990s with the Canon EOS-1 (Japan) of 1989.
    • 1979 Pentax ME Super (Japan): first SLR with primarily electronic push button controls. Had increase/decrease push buttons for shutter speed selection instead of a traditional shutter speed dial.
    • 1980: Ricoh XR-7 and XR-S (Japan): first SLR with viewfinder LCD. LCD showed pseudo-meter needle pointing along a shutter speed scale to indicate light meter recommended settings.
    • 1980: Nikon F3 (Japan): first SLR with viewfinder LCD digital data display. LCD only showed shutter speeds. As computerized SLR features multiplied, comprehensive viewfinder LCD displays became normal in virtually all 35 mm SLRs by the late 1980s.
    • 1981: Pentax ME F (Japan): first built-in autofocus 35 mm SLR. Had passive contrast detection AF system. Autofocused poorly and was not commercially successful. Also had Pentax K-F mount, the first electric contact bayonet lens mount for interchangeable lens cameras. It was used only by the Pentax ME F body and SMC Pentax AF 35mm-70mm f/2.8 Zoom Lens.
    • 1982: Polaroid SLR 680 (USA): first SLR with built-in electronic flash. Had active sonar AF system. Took ten exposure, 3⅛×3⅛ inch frame Polaroid 600 instant film packs. Was improved Polaroid SX-70 Sonar AF SLR with almost-all plastic (acrylonitrile butadiene styrene (ABS)) body, built-in flash and faster film. The SLR 680 represents the zenith of instant photography and was the finest instant camera ever made. The popularity of instant photography waned throughout the 1980s as auto-everything 35 mm point-and-shoot cameras and fast one-hour film developing became common.
    • 1983: Pentax Super A (Japan; called Super Program in USA): first SLR with external LCD data display. With push buttons for shutter speed selection instead of a shutter speed dial, Super Program used an LCD to show set shutter speed. As computerized SLR features multiplied, large external LCD panels became normal on virtually all 35 mm SLRs by the late 1980s.
    • 1983: Nikon FA (Japan): first camera with multi-segmented (or matrix or evaluative; called Automatic Multi-Pattern) light meter. Had a built-in computer to analyze light levels in different segments of the field of view for convenient exposure control in difficult lighting situations. Earlier metering systems could be fooled 10+% of the time, and matrix metering systems became virtually standard in 35 mm SLRs by 1990. Modern matrix meters are virtually 100% technically accurate, although the photographer may wish to alter the settings for artistic purposes.
    • 1983: Olympus OM-4 (Japan): first camera with built-in spot-meter (2% of view; 3.3ş with 50 mm lens). Meter could measure eight individual spots and average them for precise exposure control in difficult lighting situations. Spotmeters versus matrix meters represent the opposite ends of the light meter spectrum: fully manual contemplative metering versus completely computerized instantaneous metering.
    • 1985: Minolta Alpha 7000 (Japan; called Maxxum 7000 in USA): first commercially successful autofocus 35 mm SLR, first passive phase comparison AF SLR, first system AF SLR, first SLR with built-in motorized auto-rewind. Well integrated PASM autoexposure and built-in motor winder design with very good interchangeable lenses and large accessory system. Ever since the first autofocus camera, the non-SLR Konica C35 AF 35 mm P/S of 1977 (with its built-in passive electronic rangefinder system), AF had been common in 35 mm point-and-shoot cameras. The phenomenal success of the Maxxum immediately made the AF SLR the dominant 35 mm SLR type.
    • 1987: Pentax SFX (Japan; called SF1 in USA): first 35 mm SLR with built-in electronic flash. Built-in flashes for convenient auxiliary light in dim situations or for fill-light in high contrast situations had been common on point-and-shoot cameras since the mid 1970s and became standard on all but the most expensive cameras by the early 1990s.
    • 1987: Canon EF mount (Japan): first all-electronic contact camera lens mount for interchangeable lens cameras. Introduced by Canon EOS 650 and EOS 620 SLR bodies and Canon EF lenses. Mechanical camera-to-lens linkages can link auto-diaphragm lenses and instant return mirror, focal plane shutter SLRs, but electronic autofocus required additional electronic controls. Canon decided to place everything under electronic control, even though it meant that earlier Canon lenses would not be usable with the new bodies.
    • 1989 Yashica Samurai Z-L (Japan): first SLR intentionally designed for left-handed operation. Took up to 72 exposures of horizontal 18×24 mm single frames (also called half frames) on 135 type film. Had fixed autofocus 25–75 mm f/4–5.6 zoom lens, built-in motor drive and electronic flash. Was mirror copy of auto-everything, point-and-shoot Samurai Z camera.
    • 1991: Kodak Digital Camera System DCS (USA/Japan): first digital still capture SLR. Heavily modified Nikon F3 35 mm SLR and MD-4 motor drive with 1024×1280 pixel (1.3 MP) charge-coupled-device (CCD) sensor, 8 MB DRAM memory and 200 MB tethered hard drive. Used manual focus Nikon F mount lenses with 2× lens field of view factor compared to standard 135 film. List price was US$19,995 (standard Nikon F3HP was US$1295 list; MD-4, US$485). Digital still (then called still video) photography first demonstrated in original Sony Mavica (Japan) prototype camera in 1981. Digital photography did not in any way alter the basic focal plane shutter, instant return mirror, pentaprism, and auto-diaphragm lens formula of SLR camera design developed over the previous century.
    • 1992: Nikonos RS (Japan): first waterproof 35 mm system SLR for 100 m maximum depth, underwater diving use. Had autofocus, autoexposure, TTL autoflash, excellent interchangeable lenses and good accessory system.
    • 1996: Minolta Vectis S-1 (Japan/Malaysia): first APS IX240 film SLR. Took up to forty exposures of 16.7×30.2 mm frames on polyethylene napthalate base, singly-perforated 24 mm wide film coated with invisible magnetic data encoding stripe, pre-loaded into self-locking ready-to-use cartridges. Had flat-topped non-pentaprism sideways mirror reflex and optical relay viewfinder. Compact design with good lenses and large accessory system. APS cameras were introduced by Kodak, Canon, Fuji, Minolta and Nikon in 1996 as Kodak's last attempt (of many) at drop-in film loading. APS failed because, with motorized autoloading perfected, manual 135 film loading was not an issue anymore; because it was more expensive than 135, without any compelling offsetting benefits and because the late 1990s was when digital photography was gaining momentum. APS was never very popular and was almost dead by 2002.
    • 2003: Canon EOS 300D (Japan; called EOS Digital Rebel in USA): first sub-US$1000 high-resolution digital SLR. Well integrated focal plane shutter, instant return mirror, pentaprism, auto-diaphragm, autoexposure, matrix-metering, autofocus, built-in autoflash, computer-controlled design with excellent lenses and good accessory system. Took up to 2048×3072 pixel (6.3 MP) digital images using a 15.1×22.7 mm complementary metal-oxide-semiconductor (CMOS) sensor (1.6× lens factor). With an original list price of US$899 (body only; US$999 with 18-55 mm f/3.5-5.6 Canon EF-S zoom lens), it sold 1.2 million units in eighteen months and was primarily responsible for digital SLR sales vaulting past film SLR sales in the USA in 2004.

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    In photography, exposure is the total amount of light allowed to fall on the photographic medium (photographic film or image sensor) during the process of taking a photograph. Exposure is measured in lux seconds, and can be computed from exposure value (EV) and scene luminance.

    Long exposure with soft red light

    Correct exposure
    The "correct" exposure for a photograph is determined by the sensitivity of the medium used. For photographic film, sensitivity is referred to as film speed and is measured on a scale published by the International Organization for Standardization (ISO). Faster film requires less exposure and has a higher ISO rating. Exposure is a combination of the length of time and the level of illumination received by the photosensitive material. Exposure time is controlled in a camera by shutter speed and the illumination level by the lens aperture. Slower (longer) shutter speeds and greater (bigger) lens apertures produce greater exposures. The electronics in a digital camera may allow one to adjust the sensitivity of the CCD or CMOS sensor. ISO numbers are usually used to express this attribute.
    An approximately correct exposure will be obtained on a sunny day using ISO 100 film, an aperture of f/16 and a shutter speed of 1/125th of a second. This is called the sunny 16 rule: at an aperture of f/16 on a sunny day, a suitable shutter speed will be one over the film speed (or closest equivalent).
    Ultimately there is no such thing as "correct exposure", as a scene can be exposed in many ways, depending on the desired effect a photographer wishes to convey.


    An important principle of exposure is reciprocity. If one exposes the film or sensor for a longer period, a reciprocally smaller aperture is required to reduce the amount of light hitting the film to obtain the same exposure. For example, the photographer may prefer to make his sunny-16 shot at an aperture of f/5.6 (to obtain a shallow depth of field). As f/5.6 is 3 stops 'faster' than f/16, with each stop meaning double the amount of light, a new shutter speed of (1/125)/(2·2·2) = 1/1000 is needed. Once the photographer has determined the exposure, aperture stops can be traded for halvings or doublings of speed, within limits.

    A demonstration of the effect of exposure in night photography. Longer shutter speeds mean increased exposure.

    The true characteristic of most photographic emulsions is not actually linear, (see sensitometry) but it is close enough over the exposure range of about one second to 1/1000th of a second. Outside of this range, it becomes necessary to increase the exposure from the calculated value to account for this characteristic of the emulsion. This characteristic is known as reciprocity failure. The film manufacturer's data sheets should be consulted to arrive at the correction required as different emulsions have different characteristics.
    Digital camera image sensors can also be subject to a form of reciprocity failure.[1]

    Determining exposure

    Long exposures can create very interesting photos.

    The zone system is another method of determining exposure and development combinations to achieve a greater tonality range over conventional methods by varying the contrast of the 'film' to fit the print contrast capability. Digital cameras can achieve similar results (high dynamic range) by combining several different exposures (varying only the shutter speeds) made in quick succession.
    Today, most cameras automatically determine the correct exposure at the time of taking a photograph by using a built-in light meter, or multiple point meters interpreted by a built-in computer, see metering mode.
    Negative/Print film tends to bias for exposing for the shadow areas (film dislikes being starved of light), with digital favouring exposure for highlights. See latitude below.


    Latitude is the degree by which you can over, or under expose an image, and still recover an acceptable level of quality from an exposure. Typically negative film has a better ability to record a range of brightness than slide/transparency film or digital. Digital should be considered to be the reverse of print film, with a good latitude in the shadow range, and a narrow one in the highlight area; in contrast to film's large highlight latitude, and narrow shadow latitude. Slide/Transparency film has a narrow latitude in both highlight and shadow areas, requiring greater exposure accuracy.
    Negative film's latitude increases somewhat with high ISO material, in contrast digital tends to narrow on latitude with high ISO settings.


    Example image exhibiting blown-out highlights. Top: original image, bottom: blown-out areas marked red

    Areas of a photo where information is lost due to extreme brightness are described as having "blown-out highlights" or "flared highlights".
    In digital images this information loss is often irreversible, though small problems can be made less noticeable using photo manipulation software. Recording to RAW format can ameliorate this problem to some degree, as can using a digital camera with a better sensor.
    Film can often have areas of extreme overexposure but still record detail in those areas. This information is usually somewhat recoverable when printing or transferring to digital.
    A loss of highlights in a photograph is usually undesirable, but in some cases can be considered to "enhance" appeal. Examples include black-and-white photography and portraits with an out-of-focus background.


    Areas of a photo where information is lost due to extreme darkness are described as "crushed blacks". Digital capture tends to be more tolerant of underexposure, allowing better recovery of shadow detail, than same-ISO negative print film.
    Crushed blacks cause loss of detail, but can be used for artistic effect.

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    Default Estetica In Fotografie


    Plasarea subiectului in cadrul fotografic are o mare importanta estetica. De regula se evita plasarea subiectului in centrul cadrului (fig. b) deoarece acesta devine atat de puternic incat estompeaza toate celelalte elemente ale cadrului, acestea putand foarte bine sa nici nu fie. Astfel ca este recomandata folosirea linilor si a punctelor forte (fig. a & c), aceasta facand ca importanta unui singur element sa scada sporind efectul artistic. Pentru a evita simetria cauzata de axa orizontala [de simetrie] a cadrului, se va evita plasarea linii orizontului pe aceasta.
    Poate va intrebati cum incadram un portret dupa aceasta regula. Nimic mai simplu. Vom inclina cadrul astfel incat zona ochilor sa fie in dreptul unuia dintre punctele forte de sus ale cadrului, iar buzele vor fi pe diagonala intr-unul din punctele de forte de jos ale cadrului. (Faceti un mic exercitiu ci inchipuitiva [sau chiar incercati] ca priviti drept prin vizorul aparatului, iar apoi inclinati aparatul spre dreapta sau stanga si veti descoperi ca modelul se va potrivi perfect conform acestor puncte forte.)

    Diagonala forte (fig. d) este utilizata atunci cand se doreste scoaterea in evidenta a subiectului, iar diaginala slaba (fig. e) este utilizata atunci cand se doreste estomparea unor elemente compozitionale ale subiectului.
    Acestea din urma fiind valabile celor care scriu de la stanga la dreapta pentru ca au stransa legatura cu felul de a privi [de la stanga la dreapta].


    Perspectiva liniara. Veti observa ca atunci cand aveti un cadru suficient de "adanc" liniile paralele ale soselei sau ale caii ferate desi paralele, la un moment dat par sa se uneasca. Iar pomii de pe marginea soselei desi avand cam aceeasi dimensiune par din ce in ce mai mici. Acesta este efectul perspectivei liniare, care ne sugereaza ideea de departare, de adancime.
    Deformarea perspectivei apare atunci cand aparatul de fotografiat si obiectivul acestuia capteaza imaginea altfel decat o percepe ochiul uman. Spre exemplu un obiectiv un obiectiv cu distanta focala scurta (superangular - wide angle) accentueaza perspectiva, pe cand unul cu distanta focala lunga (teleobiectiv) diminueaza perspectiva. Distanta focala normala pentru aparatele de format 35mm(24x36) este f:50mm iar pentru formatul mediu este de f:80mm.

    Sunt trei feluri de perspectiva liniara. 1. Perspectiva normala (fig. a). 2. Perpectica de jos in sus [de broasca] (fig. b). 3. Perspectiva de sus in jos [a pasarii in zbor] (fig. c). Observati cum fiecare dintre aceste tipuri de perspectiva influenteaza proportionarea elementelor din cadru.

    Perspectiva aeriana. Reprezinta diminuarea culorilor si a detaliilor pana cand acestea devin incetosate si de culoare albastruie, pierzandu-se in departare.

    Cum să facem oamenii să arate bine în fotografii
    (Dinu Lazăr)

    Lumina: de obicei nu ne gândim prea mult la iluminare când avem de fotografiat un subiect care este grăbit sau nu cooperează cu fotograful. Lumina folosită însă ajută cel mai mult la redarea unei imagini de bună calitate. Dacă subiectul este în aer liber, stim cu totii zicala: "cu soarele în spate". Dar asta nu ajută prea mult pe subiect, care în mod sigur o să închidă ochii din cauza luminii directe prea puternice. Solutia este de a ruga subiectul să nu privească direct în Soare, si să compensăm umbrele apărute pe fată cu un flash. În interior, asează subiectul aproape de fereastra si foloseste lumina difuză de afară. Un film de sensibilitate mare, 400 ISO/ASA, o să ajute la reducerea contrastului si la obtinerea unui timp de expunere suficient de mic pentru o expunere clară.

    Unghiul de fotografiere: alege un unghi care favorizează subiectul. Aparatul trebuie să fie la nivelul ochilor subiectului, dar dacă vrem să "ascundem" niste imperfectiuni, putem să schimbăm unghiul.

    Încadrează cât mai mult subiectul: eliminând elementele neesentiale din imagine, ajută la accentuarea subiectului. Vino aproape de subiect, încadrează de la mijloc în sus, foloseste un tele obiectiv sau zoom tele.

    Atentie la ochi
    : ochii sunt de multe ori partea cea mai interesantă la o persoană. Un flash direct de pe aparat în mod sigur o să rezulte în asa zisii "ochi de pisică", pete rosii pe hârtie acolo unde ochii erau de fapt albastrii. Foloseste flashul cu lumina reflectată din tavan sau dintr-un perete (de preferintă alb de culoare), si o să obtii o lumină difuză plăcută, fără contraste mari pe fată.

    Terapia de grup: strânge un grup de oameni atât cât permite spatiul, fără să se urce unul în spinarea altuia. tine minte că fetele sunt cele mai importante si lasă picioarele unde sunt. Nu uita de "uite păsărica!" si totul o să fie bine.

    Subiect, Compozitie, Fotografie

    (pentru începători... si nu numai) de Gicu Serban, Sibiu

    În realizarea unei fotografii bune, determinant este interesul sincer al fotografului fată de subiect. Acesta este primul pas în realizarea unei fotografii care să reprezinte cu adevărat subiectul. Din păcate majoritatea fotografilor neglijează acest aspect (al subiectului) punând în prim plan partea tehnică a realizării fotografiei (aparatul, obiectivul, filtru, ultimele achizitii în acest domeniu). Astfel se explică multitudinea de fotografii care "nu spun nimic", plictisitoare, lipsite de interes. Asadar succesul sau insuccesul fotografiei este în primul rând rezultatul atitudinii fotografului fată de subiect combinată cu abordarea prin mijloace tehnice a subiectului.
    Fotograful pus în fata subiectului ales trebuie să-l înteleagă, să intre în legătură cu el. Să afle ceea ce e caracteristic pentru acel subiect, ce trebuie scos în evidentă, ce trebuie eliminat. Toate fotografiile vor reprezenta viziunea fotografului asupra acelui subiect. Dacă acelasi subiect va fi imortalizat de doi fotografi imaginile lor vor fi diferite.
    Ce privim prin vizorul aparatului fotografic? Ce proportii folosim între latura mică si latura mare? Cum facem încadrarea? Pe lat sau pe înalt? Unde trebuie plasate obiectele?
    Iată câteva întrebări la care fotograful amator trebuie să-si răspundă înainte de a realiza o fotografie de calitate. În rândurile de mai jos încercăm să dăm câteva răspunsuri.
    Ce privim prin vizorul aparatului fotografic? La prima privire prin vizorul aparatului observăm o însiruire de subiecte plasate în cadru într-o anumită ordine sau răspândite la întâmplare. Astfel, suprafata cadrului contine o multitudine de elemente si posibile subiecte care se oferă fotografului. El trebuie să discearnă ce anume va păstra în cadru si ce va elimina. Ce este mai reprezentativ si ce nu este. Păstrează toate detaliile, câteva sau numai unul singur care să reprezinte subiectul. Această alegere este una din cele mai importante în procesul realizării unei fotografii.
    Ce proportii folosim între latura mică si latura mară? Cum facem încadrarea? Pe lat sau pe înalt? Proportiile între latura mică si cea mare a fotografiei corespund formatelor standard de filme si de hârtie fotografică. Sunt proportii armonioase folosite la majoritatea fotografiilor. Fotograful nu este totusi obligat să respecte aceste standarde, alte formate putând contribui la redarea subiectului în modul în care fotograful doreste. Asadar avem un dreptunghi cadru. Acest dreptunghi îl putem aseza pe latura mică sau pe cea mare (pe orizontală sau pe verticală). Din păcate considerentul după care se face această alegere la majoritatea fotografilor amatori este bazat pe ideea că "pe înalt prind si vârful muntelui, crucea bisericii ...etc."
    Formatul pe orizontală sugerează stabilitate (latura de jos sugerează pământul, cea de sus cerul, cadrul impune stabilitate). Asadar pentru subiectele de tipul: peisaj în liniste, odihnă, deplasare pe orizontală etc. vom alege în majoritatea cazurilor încadrarea pe orizontală.
    Încadrarea pe verticală pare instabilă, pare că "se poate răsturna". În cazul unor subiecte cum ar fi: deplasare pe verticală, deplasare în adâncime, tensiune, înăltime etc. este indicată încadrarea pe verticala.
    Formatul pătrat de fotografie se potriveste cel mai bine la compozitii simetrice.
    Unde trebuie plasate obiectele? În general tendinta la fotografii amatori este aceea de a plasa subiectul în mijlocul cadrului. Această plasare a subiectului este neindicată. Dacă privim subiectul pentru câteva clipe constatăm că nu-l mai vedem decât pe el. Excesul de simetrie face ca alte detalii din fotografie să se estompeze până la disparitie. Asadar centrul fotografiei este considerat un punct slab al cadrului. În general subiectul se plasează în centrul fotografiei în compozitiile unde este nevoie de o constructie foarte echilibrată.
    Punctele si liniile forte ale unei fotografii sunt pozitiile cele mai indicate pentru plasarea principalului element compozitional al fotografiei.
    Aceste modele de compozitie sunt doar principii de bază. Există foarte multe lucrări considerate foarte reusite care nu respectă aceste modele. O fotografie construită după aceste principii nu va fi ratată. Îndepărtarea de la aceste principii poate conduce la o fotografie foarte bună sau foarte rea.
    (19E+13E+5E+1W)*(H-H)@1m + SS2/TeViiS660 + DigiBox + AKTA on 42LD650 3GS

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    by Klaus Schroiff Topics: The very Basics ... or 18% gray

    Metering systems are calibrated to a certain light value in order to gurantee constant exposure settings: 18% gray is commonly accepted because a typical scene seems reflect the same amount of light as this gray value. As a framework for comparison all these colors reflect light like 18% gray:

    Usually this assumption works pretty good but if you expose a scene with a majority of bright colors/grays without compensation in spot or center-weighted mode the camera will darken the picture to 18% gray - the result is under-exposed. On the contrary a scene with lots of very dark colors/grays will be lightened up to this gray value - the result is over-exposed. The camera cannot differ between a white wall in shade or a gray wall in sunshine because the amount of incoming ligth is identical. Most cameras are blind in regard to colors - with just one exception (the Nikon F5) they analyse the world based on different light values.
    Negative Example (w/single segment metering system):
    real scene with -say-
    10% gray on the avarage
    the camera sees image as if it's 18% gray ------>
    resulting image
    18% gray
    Typical spots with risks for under-exposure:
    • Beach
    • Snow
    • cloudy Sky
    Examples with risks for over-exposure:
    • Forest
    • Lakes
    • Dusk or dawn (lots of shadows)
    Dependent on the situations you'll have to compensate up to 2 EV to longer or shorter shutter speeds (fixed aperture) or more or less f-stops (fixed shutter speed). Just "shifting the program" doesn't change the amount of light transmitted to the film.
    Note: Print films are very tolerant to wrong exposure while slide films require an accurate metering result. 1-2 EV difference compared to the optimal setting doesn't make a difference with prints whereas a slide image is usually quality for the trash bin in such a case.

    Common Metering Modes (SLR-cameras)

    Metering Modes Spot/Partial Center-weighted Multi-zone/Matrix Metering characteristic Technical: This mode limits the metering area to the central part of the viewfinder. Spot metering covers about 1% to 3.5% of the image area (typically 3.5%). Partial metering covers about 9.5%. Metering is averaged over the entire scene with emphasis placed on the center area (typically 75% center - marked dark gray and black in the icon, 25% outside). The exposure setting is calculated based on data from matrix/segment elements (3 to 16 or more, typically 6) taking into account such factors as the focusing point in use, subject size, position, distance, overall lighting level, front and back lighting and color. Use this mode ... ... when there're big differences in brightness
    (e.g. between foreground and background) or for subjects that require precise measurement, such as close-up photography. ... when you main subject covers a large portion of your image (e.g. with peripheral shadows) ... for general subjects without larger shadowed or extreme bright areas. Action photography. Advantages: Precise metering in your control. Metering mode for general scenes with relatively easy exposure compensation control. Comfortable with good reliability. Problems: Heavy variations in metering results. Bracketing is surely a good idea for the more extreme situations. Without compensation risk of over-exposing for scenes with major picture areas covered by sky. No control of the exposure settings - you simply don't exactly know how the camera weights the elements. The following illustation provides an impression about the way modern matrix metering systems work. Basically the camera processes the metering pattern by weighting the data with the selected AF sensor(s) and compares this information with an an internal scene database. Usually it'll try to avoid extreme compensation factors to reduce the risk of a total misinterpretation of a scene. Unfortunate this policy will often fail especially in contra light situations.

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    Typical scenes for Spot or Partial Metering

    You should be aware of the followings points:
    • Don't meter to the brightest spot of the scene - this would lead to underexposed results. Try to find a place which has to be exposed right but always think of the limitation of the metering system.
    • Even spot or partial metering cover a substantial area of the picture (up to 9.5%). E.g. the partial metering in the big picture (slot canyon) above points to a very bright spot but it surely contains some of the shadowed areas - in this special case it leads to a correct result.
    • Normally print films can process a range of around 7 EV=f-stops (slide film: up to 5 EV) so you should choose spots which are a little bit darker than shown in the pictures above. If the amount of contrast in a scene exceeds the limitations of the film your main subject will be outshined or a "skyline"-effect will occure. You can use the latter as a stylistic element like in the picture to the lower left (looks better projected than scanned).
      You can gain 1 EV by pre-exposing the film:
      • switch to multi-exposure mode (#2)
      • pre-expose with a high-shutter speed and small aperture to a blank paper (e.g. 1/2000s, f/22)
      • expose your picture (non-compensated)
      "Black" will probably not as dense as normal but there shouldn't be any further side-effects.

    Typical scenes for Center-weighted Metering

    Try to find a larger area which has to be exposed right and -again- think of the limitation of the metering system. In critical situations try to compensate manually which can be well controlled in this mode or change to spot metering.

    Typical scenes for Matrix or Multi-zone Metering

    Multi-zone metering systems are very easy to use. In primitive cases just POINT & SHOOT. Manual compensation isn't very reliable with difficult scenes because you simply don't know exactly how the camera calculates the settings. After some usage you may get a certain feeling for its reactions in certain situations.

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    Si acum un exemplu practic despre influenta aperturii asupra adancimii de focalizare. Pozele de mai jos le-am facut fara
    stativ, la repezeala, fiinca ploua.
    Ambele sunt in modul AV, distanta focala 34 mm, ISO 200.
    Prima poza are F5,6 si T1/80 Observati fundalul neclar din cauza aperturii mari:

    Si acum cu F29 si T1/3. Fundalul e mai clar, dar datorita timpului mare de expunere iti trebuie mana buna sau stativ (sau
    sa rogi vantul sa nu bata):

    Din ciclul "copacii mei e cei mai frumosi". Copacelul din imagine are 1,5 m inaltime si se numeste "acer palmatus japonicus".

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    Lenses can be categorized in two ways: whether it's focal length is fixed or changeable and its focal length measurement.

    Fixed vs. Changeable Focal Length

    Let's say you are taking a picture of a group. How you take their picture is totally dependent on what type of lens your camera has. Prime lenses have a fixed focal length which means that you cannot change your field of view. If you want to to fill the frame with your friends then you have to physically move closer to them. The zoom lenses'focal length, on the other hand, can be changed. You can just stay put and zoom into your subject.

    Focal Length Measurements
    Lenses can also be categorized as either wide angle, standard or telephoto with regards to their focal length measurement in millimeters. Wide Angle Lens
    Any lens less than 28mm is considered a wide angle lens. These types of lenses are popular with landscape photographers since it allows them to take pictures that show more of the scene.

    Standard Lens
    Lenses whose focal length is between 28mm to 80mm are considered standard lenses. These are usually the ones that are bundled with new cameras or what are called kit lenses.

    Telephoto Lens
    These are the bigger lenses whose focal length is more than 80mm. These lenses are usually used by wild life and sports photographers, whose works do not allow them to get physically close to their subject.

    All the three categories above can either be a prime or a zoom lens. For example, a lens that is fixed at 50mm is called a standard prime lens, a lens that is marked as 80-200mm is called a telephoto zoom since you are able to change the focal length between 80 to 200mm.

    Another factor to consider when looking at lenses is the aperture. The aperture is basically just the opening that allows light to hit you camera's sensor which, in turn, creates the image. You can compare the aperture to the iris in your eyes. The more open it is, the more light gets in. Now you will not see any aperture value on your lens or camera but instead you will see something called a f-stop. All you need to understand as you begin learning about photography is that the lower the f-stop, the bigger the aperture opening. You can use the picture below to see the relationship between the two.

    If you set your aperture at f/2, your camera will be able to capture the image faster than it would if it was at f/8 since more light hits your sensor at f/2. If you want to learn more details about apertures and f-stops then you can go here.

    The maximum aperture opening or lowest f-stop is clearly marked on camera lenses. It is the number found after the mark "1:". The reason for this is that not all lenses have the same maximum aperture but all can go to at least f/22 on the other end. Some lenses can only go up to f/3.5 while some can go to f/1.8. The lower the maximum aperture, the faster the lens is (again because it can open wider to let in more light).

    It's an ongoing joke that the maximum aperture is stated on the lens because, the lower the f-stop, the more expensive the lens is. On some zoom lenses, you can see two maximum aperture numbers. Let's take the Canon lens 18-55mm 1:3.5-5.6. This means that the maximum aperture depends on what you set your focal length to. The first number, in this case 3.5, is the maximum aperture setting at the wide-angle side of the lens i.e. 18mm. The second number, 5.6, is the maximum at it's telephoto side i.e. 55mm. The difference due to the movement of the lenses when you're actually zooming in or out.

    Depth of Field
    What's useful about understanding even just a little bit about f-stops is that it controls how much of your picture is in focus or the depth of field. For the picture below, an f-stop of f/11 was selected and the light green pencil in the middle was the point of focus. You can see that all the pencils in frame are in focus. This is what is called a deep depth of field.

    For the next picture, an f-stop of f/1.8 was selected and the light green pencil was again the point of focus. What you'll notice is that the farther you move away from the point of focus, the less sharp the image becomes. This is called a shallow depth of field.

    The lower the f-stop, the more shallow your depth of field is and vice versa. So if you want to take a landscape picture with everything in focus, you will need to select a high f-stop like f/16. If you want to focus on one specific object and throw everything else out of focus then select a low f-stop.

    Lens Markings

    - Using the picture on the left, you can tell that it is a zoom lens since you can change the focal length between 24-120mm.

    - Since the focal length 24-120mm mainly falls within the standard range, this is considered a standard zoom lens.

    - The maximum aperture of the lens if it's at 24mm us 3.5.

    -The maximum aperture of the lens when it's at 120mm is 5.6.



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