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Pentax ME F
The Pentax ME F was an amateur level, interchangeable lens, 35 mm film, single-lens reflex (SLR) camera. It was manufactured by Asahi Optical Co., Ltd. of Japan from November 1981 to 1984. The ME F was a heavily modified version of the Pentax ME-Super, and a member of the Pentax M-series family of SLRs (see List of Pentax products). It was the first mass-produced SLR camera to come with an autofocus system. Significance and market position The ME F is a historically significant camera. It was the first autofocus (AF) 35 mm SLR camera to reach production. It had a built-in through-the-lens (TTL) electronic contrast detection system to automatically determine proper subject focus and drive a lens to that focus point. Although it autofocused poorly and was a commercial failure, the pioneering ME F was a major milestone in the history of camera technology that pointed the way to all present day AF SLRs. Most new cameras today, whether film, video or digital, have some sort of ...
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Pentax
is a brand name used primarily by the Japanese multinational imaging and electronics company Ricoh for DSLR cameras, lenses, sport optics (including binoculars and rifle scopes), and CCTV optics. The Pentax brand is also used by Hoya Corporation for medical products & services, TI Asahi for surveying instruments, and Seiko Optical Products for certain optical lenses. Corporate history Early history The company was founded as Asahi Kogaku Goshi Kaisha in November 1919 by Kumao Kajiwara, at a shop in the Toshima suburb of Tokyo, and began producing spectacle lenses (which it still manufactures). In 1938 it changed its name to , and by this time it was also manufacturing camera/cine lenses. In the lead-up to World War II, Asahi Optical devoted much of its time to fulfilling military contracts for optical instruments. At the end of the war, Asahi Optical was disbanded by the occupying powers, being allowed to re-form in 1948. The company resumed its pre-war activities, manufactur ...
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Pentax MX
The Pentax MX was a 35 mm single-lens reflex camera produced by Asahi Optical Co, later Pentax of Japan between 1976 and 1985. It was Pentax's flagship professional SLR until the introduction of the Pentax LX. Internally, the MX is essentially a smaller, lighter version of the Pentax KX, and otherwise has little in common with the rest of the Pentax M-series. However, the MX was designed as the mechanical twin sister of the remarkably successful entry-level Pentax ME. The MX was solidly built, and featured a fully mechanical construction, including a mechanical shutter of the horizontal cloth type. Only the light metering system was dependent on batteries. The MX is all manual: it does not feature autofocus or autoexposure modes such as aperture-priority, shutter-speed priority, or full program. A number of accessories were produced, among those: Focusing Screens * SC1: ground glass, split image device, microprism ring (standard) * SA1: ground glass, microprism patch * ...
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Light Meter
A light meter is a device used to measure the amount of light. In photography, a light meter (more correctly an exposure meter) is used to determine the proper exposure (photography), exposure for a photograph. The meter will include either a Digital data, digital or analog calculator which displays the correct shutter speed and f-number for optimum exposure, given a certain lighting situation and film speed. Similarly, exposure meters are also used in the fields of cinematography and scenic design, in order to determine the optimum light level for a scene. Light meters are used in the general field of architectural lighting design to verify proper installation and performance of a building lighting system, and in assessing the light levels for growing plants. Use in photography The earliest type of light meters were called ''Complex index of refraction, extinction meters'' and contained a numbered or lettered row of neutral density filters of increasing density. The p ...
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Photodiode
A photodiode is a light-sensitive semiconductor diode. It produces current when it absorbs photons. The package of a photodiode allows light (or infrared or ultraviolet radiation, or X-rays) to reach the sensitive part of the device. The package may include lenses or optical filters. Devices designed for use specially as a photodiode use a PIN junction rather than a p–n junction, to increase the speed of response. Photodiodes usually have a slower response time as their surface area increases. A photodiode is designed to operate in reverse bias. A solar cell used to generate electric solar power is a large area photodiode. Photodiodes are used in scientific and industrial instruments to measure light intensity, either for its own sake or as a measure of some other property (density of smoke, for example). A photodiode can be used as the receiver of data encoded on an infrared beam, as in household remote controls. Photodiodes can be used to form an optocoupler, allowing tra ...
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Light-emitting Diode
A light-emitting diode (LED) is a semiconductor Electronics, device that Light#Light sources, emits light when Electric current, current flows through it. Electrons in the semiconductor recombine with electron holes, releasing energy in the form of photons. The color of the light (corresponding to the energy of the photons) is determined by the energy required for electrons to cross the band gap of the semiconductor. White light is obtained by using multiple semiconductors or a layer of light-emitting phosphor on the semiconductor device. Appearing as practical electronic components in 1962, the earliest LEDs emitted low-intensity infrared (IR) light. Infrared LEDs are used in Remote control, remote-control circuits, such as those used with a wide variety of consumer electronics. The first visible-light LEDs were of low intensity and limited to red. Early LEDs were often used as indicator lamps, replacing small Incandescent light bulb, incandescent bulbs, and in seven- ...
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Metal Oxide Semiconductor
The metal–oxide–semiconductor field-effect transistor (MOSFET, MOS-FET, or MOS FET) is a type of field-effect transistor (FET), most commonly fabricated by the controlled oxidation of silicon. It has an insulated gate, the voltage of which determines the conductivity of the device. This ability to change conductivity with the amount of applied voltage can be used for amplifying or switching electronic signals. A metal-insulator-semiconductor field-effect transistor (MISFET) is a term almost synonymous with MOSFET. Another synonym is IGFET for insulated-gate field-effect transistor. The basic principle of the field-effect transistor was first patented by Julius Edgar Lilienfeld in 1925.Lilienfeld, Julius Edgar (1926-10-08) "Method and apparatus for controlling electric currents" upright=1.6, Two power MOSFETs in V_in_the_''off''_state,_and_can_conduct_a_con­ti­nuous_current_of_30  surface-mount_packages._Operating_as_switches,_each_of_these_components_can ...
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Focus Assistance
Focus, or its plural form foci may refer to: Arts * Focus or Focus Festival, former name of the Adelaide Fringe arts festival in South Australia Film *''Focus'', a 1962 TV film starring James Whitmore * ''Focus'' (2001 film), a 2001 film based on the Arthur Miller novel * ''Focus'' (2015 film), a 2015 film about con artists Music * Focus (music), a musical technique also known as modal frame * Focus..., American music producer * Focus (band), Dutch progressive rock band Albums * ''Focus'' (Stan Getz album), 1961 jazz album * ''Focus'' (Bill Hardman album), 1984 jazz album * ''Focus'' (Jan Akkerman & Thijs van Leer album), 1985 * ''Focus'' (Cynic album), 1993 metal album * ''Focus'' (Chico Freeman album), 1994 jazz album * ''Focus'' (Souls of Mischief album), 1998 alternative hip-hop album * ''Focus'' (Holly Starr album), 2012 CCM album * ''Focus'' (Arthur Blythe album), 2002 jazz album * ''Focus'' (Diaura album), 2013 Japanese visual kei album Songs * "Focus" (Ari ...
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K Mount
The Pentax K-mount, sometimes referred to as the "PK-mount", is a bayonet lens mount standard for mounting interchangeable photographic lenses to 35 mm single-lens reflex (SLR) cameras. It was created by Pentax in 1975, and has since been used by all Pentax 35 mm and digital SLRs and also the MILC Pentax K-01. A number of other manufacturers have also produced many K-mount lenses and K-mount cameras. Mounts The Pentax K-mount has undergone a number of evolutions over the years as new functionality has been added. In general, the term K-mount may refer to the original K-mount, or to all its variations. Originally designed by Zeiss for an alliance with Pentax, it was intended to be a common lens mount for a proposed series of cameras and lenses. However, the plan failed to work out and the two firms parted company amicably, but Pentax retained the lens mount and at least one Zeiss lens design for its own use. K-mount The original K-mount is a simple bayonet c ...
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Focal Plane Shutter
In camera design, a focal-plane shutter (FPS) is a type of photographic shutter that is positioned immediately in front of the focal plane of the camera, that is, right in front of the photographic film or image sensor. Two-curtain shutters The traditional type of focal-plane shutter in 35 mm cameras, pioneered by Leitz for use in its Leica cameras, uses two shutter curtains, made of opaque rubberised fabric, that run horizontally across the film plane. For slower shutter speeds, the first curtain opens (usually) from right to left, and after the required time with the shutter open, the second curtain closes the aperture in the same direction. When the shutter is cocked again the shutter curtains are moved back to their starting positions, ready to be released. Focal-plane shutter at low speed ''Figure 1:'' The black rectangle represents the frame aperture through which the exposure is made. It is currently covered by the first shutter curtain, shown in red. The se ...
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Seiko
, commonly known as Seiko ( , ), is a Japanese maker of watches, clocks, electronic devices, semiconductors, jewelry, and optical products. Founded in 1881 by Kintarō Hattori in Tokyo, Seiko introduced one of the first quartz watches and the first quartz watch with a chronograph complication. Seiko was a wristwatch manufacturer for Japanese soldiers during World War II. History 1881 founding to 1929 In 1881, Seiko founder Kintarō Hattori opened a watch and jewelry shop called "K. Hattori" () in Tokyo. Kintarō Hattori had been working as clockmaker apprentice since the age of 13, with multiple stints in different watch shops, such as “Kobayashi Clock Shop”, ran by an expert technician named Seijiro Sakurai; “Kameda Clock Shop” in Nihonbashi; and “Sakata Clock Shop” in Ueno, where he learned how to both sell and repair timepieces. Around the time of Seiko's founding, watchmakers in Tokyo, Osaka, and Nagoya were studying and producing pocket watches based on We ...
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Pentax ME-F (2243693437)
is a brand name used primarily by the Japanese multinational imaging and electronics company Ricoh for DSLR cameras, lenses, sport optics (including binoculars and rifle scopes), and CCTV optics. The Pentax brand is also used by Hoya Corporation for medical products & services, TI Asahi for surveying instruments, and Seiko Optical Products for certain optical lenses. Corporate history Early history The company was founded as Asahi Kogaku Goshi Kaisha in November 1919 by Kumao Kajiwara, at a shop in the Toshima suburb of Tokyo, and began producing spectacle lenses (which it still manufactures). In 1938 it changed its name to , and by this time it was also manufacturing camera/cine lenses. In the lead-up to World War II, Asahi Optical devoted much of its time to fulfilling military contracts for optical instruments. At the end of the war, Asahi Optical was disbanded by the occupying powers, being allowed to re-form in 1948. The company resumed its pre-war activities, manufactu ...
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United States
The United States of America (U.S.A. or USA), commonly known as the United States (U.S. or US) or America, is a country Continental United States, primarily located in North America. It consists of 50 U.S. state, states, a Washington, D.C., federal district, five major unincorporated territories, nine United States Minor Outlying Islands, Minor Outlying Islands, and 326 Indian reservations. The United States is also in Compact of Free Association, free association with three Oceania, Pacific Island Sovereign state, sovereign states: the Federated States of Micronesia, the Marshall Islands, and the Palau, Republic of Palau. It is the world's List of countries and dependencies by area, third-largest country by both land and total area. It shares land borders Canada–United States border, with Canada to its north and Mexico–United States border, with Mexico to its south and has maritime borders with the Bahamas, Cuba, Russia, and other nations. With a population of over 333 m ...
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