exposure meter

exposure meter
an instrument for measuring the intensity of light in a certain place or upon a certain object, having an adjustable scale for determining the optimum relations of shutter speeds and stops at each intensity. Also called light meter.
[1890-95]

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▪ photographic technology
also called  Light Meter,  

      photographic auxiliary device that measures the intensity of light and indicates proper exposure (i.e., the combination of aperture and shutter speed) for film of a specific sensitivity. Modern instruments are of two basic types: the self-generating, or photovoltaic, and the variable resistance, or photoconductive.

      The photovoltaic type, usually with a selenium element, converts the incoming light directly into an electric current. A microammeter measures this current and is calibrated to indicate the intensity of the light. Exposure is then set by adjusting dials to control aperture opening and shutter speed, taking into consideration the specific sensitivity of the film.

      In the photoconductive type, the element, a cadmium sulfide cell or silicon photodiodes, is connected to a battery-powered circuit and changes its resistance with variations in the light intensity. The change in current is measured by a milliammeter calibrated to read light intensity.

      The exposure meter is incorporated into the camera mechanism of most modern hand cameras. The operator of a semiautomatic camera model sets the correct exposure by adjusting the exposure controls to align two pointers in the viewfinder; in fully automatic cameras, the exposure is adjusted by the camera mechanism itself.

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Universalium. 2010.

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Look at other dictionaries:

  • exposure meter — n. Photog. an instrument that measures the intensity of light striking, or reflecting from, the subject, used to find the correct exposure settings; light meter …   English World dictionary

  • exposure meter — noun photographic equipment that measures the intensity of light • Syn: ↑light meter, ↑photometer • Hypernyms: ↑photographic equipment • Hyponyms: ↑cytophotometer * * * exˈposure meter 7 [ …   Useful english dictionary

  • exposure meter — eksponometras statusas T sritis Standartizacija ir metrologija apibrėžtis Įtaisas eksponavimo trukmei ir diafragmos skersmeniui nustatyti fotografuojant arba filmuojant. atitikmenys: angl. exposure meter vok. Belichtungsmesser, m rus. экспонометр …   Penkiakalbis aiškinamasis metrologijos terminų žodynas

  • exposure meter — eksponometras statusas T sritis fizika atitikmenys: angl. exposure meter vok. Belichtungsmesser, m; Exponometer, n rus. экспонометр, m pranc. exposimètre, m …   Fizikos terminų žodynas

  • exposure meter — noun An instrument that measures the intensity of the light reflected from or falling on a subject, and calculates the optimum exposure depending on the film speed. Syn: light meter, lux meter …   Wiktionary

  • exposure meter —    An instrument with a light sensitive cell that measures the light reflected from or falling on a subject; used as an aid to selecting the exposure setting. The same as a light meter …   Forensic science glossary

  • exposure meter — expo′sure me ter n. pht an instrument that measures the intensity of light in a certain place and indicates the proper photographic exposure setting Also called light meter Etymology: 1890–95 …   From formal English to slang

  • exposure meter — noun Date: 1891 a device for indicating correct photographic exposure under varying conditions of illumination …   New Collegiate Dictionary

  • exposure meter — noun Photography a light meter …   English new terms dictionary

  • exposure meter — /əkˈspoʊʒə mitə/ (say uhk spohzhuh meetuh) noun → light meter …  

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