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In photography, a viewfinder is a device on a camera that a photographer uses to determine exactly where the camera is pointed, and approximately how much of that view will be photographed. A viewfinder can be mechanical (indicating only direction and approximate view), with simple optical components, with precision optics and optical functions, or a digital accessory device used with digital cameras.
These cameras had no separate viewfinder. The exact image (although upside-down and reversed left-right) was viewed on a ground glass installed either in a replaceable plateholder, or in a spring back where springs hold the ground glass at the focus plane until a photographic plateholder is slid in front of it. Spring backs usually had a flip-up cover protecting the ground glass. A black focusing cloth was used with larger models.
Later referred to as "sports finders", for many sports and newspaper applications optical viewfinders gave too small an image and were inconvenient to use for scenes that were changing rapidly. For these purposes a simple arrangement of two wire rectangles, a smaller one nearer the eye[ citation needed ] and a larger one further away, was used, without optics; the two rectangles were aligned so the smaller one was centered in the larger, and the larger rectangle would give an indication of what would be included. Cameras with sportsfinders usually had optical viewfinders also.
A single divergent (plano-concave) lens, in front of a frame, when close to the eye, acts as a viewfinder. Adding a convergent (plano-convex) lens makes a very short reversed Galilean (upright image) telescope. For movie camera or others with changeable lenses, outline marks on one of the viewfinder lenses could show the different fields of view for the different camera lenses.
Simple reflecting viewfinders, known also as "brilliant finders", comprised a small forward-looking lens, a small mirror at 45° behind it, and a lens at the top; the user held the camera at waist level and looked down into the lens, where a small image could be seen. Such viewfinders were integrated into box cameras, and fitted to the side of folding cameras. These viewfinders were fitted to inexpensive cameras.
Twin-lens reflex (TLR) cameras use a viewfinding lens with the same focal length as the camera lens, so it has the same field of view and focus properties. With a mirror, of similar size to the film, held at 45°, it projects an upright image onto a focusing ground glass screen viewable from above. The camera can be then be held steady at waist level. Although the viewfinder lens was similar to the camera lens, the optical quality was less important and so the cost is reduced. TLR viewfinders do not have the interrupted viewing and shutter lag of the SLR type and so is preferred for dance photography. [2] Reinhold Heidecke cited his experience with periscope focusing from the German trenches in 1916 as the inspiration for the Rolleiflex line in 1929. [3] Some similar-looking cameras are actually simple box cameras with a waist-level viewfinder.
Single-lens reflex (SLR) cameras use the camera lens itself, to completely eliminate parallax, the significant field-of-view error for close subjects caused by the offset distance between the viewfinder's lens and the camera's lens. Early SLRs were plate cameras, with a mechanism to insert a mirror between the lens and the film which reflected the light upwards, where it could be seen at waist level on a ground glass screen. When ready to take the picture, the mirror was pivoted out of the way (without moving the camera). Later SLR still cameras had a mechanism which flipped the mirror out of the way when the shutter button was pressed, opened and closed the shutter, and then moved the mirror back. The Zeiss Ikon Contax S was the first SLR camera to allow easy eye-level viewing by using a roof pentaprism to laterally reverse the inverted camera image (the reflex mirror had already vertically reversed the image).[ citation needed ] SLR movie cameras used a beamsplitter partial mirror to split the camera image between the shutter and film, and the viewfinder.[ citation needed ] A major advantage of SLR viewfinders is that any change of camera lens did not affect the viewing accuracy, and accurate camera focus did not depend on correct linking or calibration.
Some sophisticated 20th century cameras with direct viewfinders had coincidence (split-image) rangefinders, initially with separate windows from the viewfinder, later integrated with it; they were called rangefinder cameras. Cameras with interchangeable lenses had to indicate the field of view of each lens in the viewfinder; more usually, interchangeable viewfinders to match the lenses were used. [4]
Viewfinders can be optical or electronic. An optical viewfinder is simply a reversed telescope mounted to see what the camera will see. Its drawbacks are many, but it also has advantages; it consumes no power, it does not wash out in sunlight, and it has "full resolution" (i.e. the resolution of the photographer's eye). An electronic viewfinder (EVF) is a CRT, LCD or OLED based display device. In addition to its primary purpose, an electronic viewfinder can be used to replay previously captured material, and as an on-screen display to browse through menus.
A still camera's optical viewfinder typically has one or more small supplementary LED displays surrounding the view of the scene. On a film camera, these displays show shooting information such as the shutter speed and aperture and, for autofocus cameras, provide an indication that the image is correctly focussed. Digital still cameras will typically also display information such as the current ISO setting and the number of remaining shots which can be taken in a burst. Another display which overlays the view of the scene is often provided. It typically shows the location and state of the camera's provided auto-focus points. This overlay can also provide lines or a grid which assist in picture composition.
It is not uncommon for a camera to have two viewfinders. For example, a digital still camera may have an optical viewfinder and an electronic one. The latter can be used to replay previously captured material, has an on-screen display, and can be switched off to save power. A camcorder may have two viewfinders, both electronic. The first is viewed through a magnifying eyepiece, and due to a rubber eyepiece it can be viewed perfectly even in bright light. The second viewfinder would be larger, of a higher resolution, and may be mounted on the side of the camera. Because it consumes more power, a method is often provided to turn it off to save energy.
In late 2010, Fujifilm announced hybrid viewfinder of optical viewfinder and electronic viewfinder in one viewfinder for its highend compact cameras. There is a half mirror prism that reflect data from LCD to the optical viewfinder, so we can see both the shooting frame and the shooting data. A button can change the hybrid function to electronical viewfinder by blocking the image through the optical viewfinder with moving a half mirror prism to be a straight up mirror. [5]
Viewfinders are used for virtually all cameras whether still or movie, film, electronic analog (Television) or digital. Many digital sensor cameras do not have a separate viewfinder. For those cameras, the electronic image is shown on a small accessory screen for composition and focusing purposes. [6] CCTVs and webcams do not need any viewfinding device.
A single-lens reflex camera (SLR) is a camera that typically uses a mirror and prism system that permits the photographer to view through the lens and see exactly what will be captured. With twin lens reflex and rangefinder cameras, the viewed image could be significantly different from the final image. When the shutter button is pressed on most SLRs, the mirror flips out of the light path, allowing light to pass through to the light receptor and the image to be captured.
A camera is an instrument used to capture and store images and videos, either digitally via an electronic image sensor, or chemically via a light-sensitive material such as photographic film. As a pivotal technology in the fields of photography and videography, cameras have played a significant role in the progression of visual arts, media, entertainment, surveillance, and scientific research. The invention of the camera dates back to the 19th century and has since evolved with advancements in technology, leading to a vast array of types and models in the 21st century.
A rangefinder camera is a camera fitted with a rangefinder, typically a split-image rangefinder: a range-finding focusing mechanism allowing the photographer to measure the subject distance and take photographs that are in sharp focus.
A twin-lens reflex camera (TLR) is a type of camera with two objective lenses of the same focal length. One of the lenses is the photographic objective or "taking lens", while the other is used for the viewfinder system, which is usually viewed from above at waist level.
An electronic viewfinder (EVF) is a camera viewfinder where the image captured by the lens is displayed on a small screen which the photographer can look through when composing their shot. It differs from a live preview screen in being smaller and shaded from ambient light, and may also use less power. The sensor records the view through the lens, the view is processed, and finally projected on a miniature display which is viewable through the eyepiece.
A point-and-shoot camera, also known as a compact camera and sometimes abbreviated to P&S, is a still camera designed primarily for simple operation. Most use focus free lenses or autofocus for focusing, automatic systems for setting the exposure options, and have flash units built in. They are popular for vernacular photography by people who do not consider themselves photographers but want easy-to-use cameras for snapshots of vacations, parties, reunions and other events.
A digital single-lens reflex camera is a digital camera that combines the optics and mechanisms of a single-lens reflex camera with a solid-state image sensor and digitally records the images from the sensor.
Contax began as a German camera model in the Zeiss Ikon line in 1932, and later became a brand name. The early cameras were among the finest in the world, typically featuring high quality Zeiss interchangeable lenses. The final products under the Contax name were a line of 35 mm, medium format, and digital cameras engineered and manufactured by Japanese multinational Kyocera, and featuring modern Zeiss optics. In 2005, Kyocera announced that it would no longer produce Contax cameras. The rights to the brand are currently part of Carl Zeiss AG, but no Contax cameras are currently in production, and the brand is considered dormant.
The Canon F-1 is a 35 mm single-lens reflex camera produced by Canon of Japan from March 1971 until the end of 1981, at which point it had been superseded by the New F-1 launched earlier that year. The Canon FD lens mount was introduced along with the F-1, but the previous Canon FL-mount lenses and older R- series lenses were also compatible with the camera with some limitations. The Canon F-1 was marketed as a competitor to the Nikon F and Nikon F2 single lens reflex cameras by Nikon.
The Canon New F-1 replaced the F-1n as Canon's top-of-the-line 35mm single-lens reflex camera in September 1981. Like the earlier models, the New F-1 takes FD-mount lenses. Although no date has ever been confirmed, it is thought that the last New F-1 was made in 1992. It was officially discontinued in 1994, and factory support ended in 2004.
The history of the single-lens reflex camera (SLR) begins with the use of a reflex mirror in a camera obscura described in 1676, but it took a long time for the design to succeed for photographic cameras. The first patent was granted in 1861, and the first cameras were produced in 1884, but while elegantly simple in concept, they were very complex in practice. One by one these complexities were overcome as optical and mechanical technology advanced, and in the 1960s the SLR camera became the preferred design for many high-end camera formats.
The Pentax LX is a 35mm single-lens reflex camera produced by Pentax in Japan. It was introduced in 1980 to commemorate the 60th anniversary of Asahi Optical Co., and was produced until 2001. It is the top-of-the-line professional, or "system", camera in the Pentax manual focus range, with manual and aperture priority automatic exposure modes and an advanced light metering system. The LX uses the K mount, which is the Pentax proprietary bayonet lens mount, and has a large body of accessories. The camera has several unique or uncommon features, and compared with contemporary professional camera bodies from rival manufacturers, like the Canon New F-1 or Nikon F3, the LX body is smaller and lighter, weighing in at 570 grams with its standard FA-1 finder.
A reflex finder is a viewfinder system with a mirror placed behind a lens. The light passing through the lens is reflected by the mirror to a focusing screen, usually ground glass. The image formed on this ground glass can be observed directly, giving a waist-level reflex finder, or through a redressing optical device for eye-level viewing, giving an eye-level reflex finder.
The Mamiya C220 is a lightweight twin-lens reflex camera made in the early 1970s by the Japanese camera manufacturer Mamiya. The camera has interchangeable lenses ranging from 55 mm wide-angle to 250 mm telephoto and accepts 120 and 220 rollfilms. The rack and pinion focusing system with a bellows makes it possible for close-up photography without attachments. The straight film path has no sharp turns for absolute flatness of the film.
A pellicle mirror is an ultra-thin, ultra-lightweight semi-transparent mirror employed in the light path of an optical instrument, splitting the light beam into two separate beams, both of reduced light intensity. Splitting the beam allows its use for multiple purposes simultaneously. The thinness of the mirror practically eliminates beam or image doubling due to a non-coincident weak second reflection from the nominally non-reflecting surface, a problem with mirror-type beam splitters. The name pellicle is a diminutive of pellis, a skin or film.
The Leica M5 is a 35 mm camera by Leica Camera AG, introduced in 1971. It was the first Leica rangefinder camera to feature through-the-lens (TTL) metering and the last to be made entirely in Wetzlar by hand using the traditional "adjust and fit" method.
The Micro Four Thirds system is a standard released by Olympus Imaging Corporation and Panasonic in 2008, for the design and development of mirrorless interchangeable lens digital cameras, camcorders and lenses. Camera bodies are available from Blackmagic, DJI, JVC, Kodak, Olympus, OM System, Panasonic, Sharp, and Xiaomi. MFT lenses are produced by Cosina Voigtländer, Kowa, Kodak, Mitakon, Olympus, Panasonic, Samyang, Sharp, Sigma, SLR Magic, Tamron, Tokina, TTArtisan, Veydra, Xiaomi, Laowa, Yongnuo, Zonlai, Lensbaby, Venus Optics and 7artisans amongst others.
Through the Viewfinder (TtV) photography is a photographic or videographic technique in which a photograph or video or motion picture film is shot with one camera through the viewfinder of a second camera. The viewfinder thus acts as a kind of lens filter. The most popular method involves using a digital camera as the image taking camera and an intact twin-lens reflex camera (TLR) or pseudo-TLR as the "viewfinder" camera. TLRs typically have square waist-level viewfinders, with the viewfinder plane at 90 degrees to the image plane. The image in a TLR viewfinder is laterally reversed, i.e. it is a mirror image. Most photographers use a cardboard tube or other apparatus connecting the two cameras in order to eliminate stray light and prevent reflections from appearing on the viewfinder glass or on the lens of the imaging camera.
The Fuji GX680 is a series of single lens reflex system cameras for medium format film produced by Fujifilm with interchangeable camera lenses and interchangeable film holders for the unusual film format 6×8 cm on 120 and 220 roll film. The distinguishing feature of the Fuji GX680 is the articulating front standard, which runs on a rail connecting lens and camera body by a bellows; the interchangeable lens is permanently mounted to a lens board.
The Mamiya 645 camera systems are a series of medium format film and digital cameras and lenses manufactured by Mamiya and its successors. They are called "645" because they use the nominal 6 cm x 4.5 cm film size from 120 roll film. They came in three major generations: first-generation manual-focus film cameras, second-generation manual-focus film cameras, and autofocus film/digital cameras.