A carbon arc lamp, cover removed, on the point of ignition. This model requires manual adjustment of the electrodes An electric arc, demonstrating the “arch” effect. Early experimental carbon arc light powered by liquid batteries, similar to Davy's Medical carbon arc lamp used to treat skin conditions, 1909 William Petrie in 1847 In popular use, the term arc lamp means carbon arc lamp only. In a carbon arc lamp, the electrodes are carbon rods in free air.
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Pavel Nikolayevich Yablochkov (also transliterated as Jablochkoff) (Павел Николаевич Яблочков in Russian) ( - ) was a Russian electrical engineer, businessman and the inventor of the Yablochkov candle (a type of electric carbon arc lamp) and the transformer.
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These are usually large portable devices that combine an extremely luminous source (usually a carbon arc lamp) with a mirrored parabolic reflector to project a powerful beam of light of approximately parallel rays in a particular direction. They have been used to create "artificial moonlight" on battlefields.
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Yablochkov candle with part of the bulb removed to show the two parallel carbon rods separated slightly from each other by a layer of plaster of Paris. A Yablochkov candle (sometimes electric candle) is a type of electric carbon arc lamp, invented in 1876 by the Russian electrical engineer Pavel Yablochkov.
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Later, a cross slide stage was used for this purpose. Vogt introduced Koehler illumination, and the reddish Nernst glower was replaced with the brighter and whiter incandescent lamp. Special mention should be paid to the experiments that followed Henker's improvements in 1919. On his improvements the Nitra lamp was replaced with a carbon arc lamp with a liquid filter.
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ATS officers-in-training crew a 90 cm searchlight in Western Command, 1944 A searchlight (or spotlight) is an apparatus that combines an extremely bright source (traditionally a carbon arc lamp) with a mirrored parabolic reflector to project a powerful beam of light of approximately parallel rays in a particular direction, usually constructed so that it can be swiveled about.
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Poulsen's first arc converter, from 1903 Elihu Thomson discovered that a carbon arc shunted with a series tuned circuit would "sing". This "singing arc" was probably limited to audio frequencies. Bureau of Standards credits William Duddell with the shunt resonant circuit around 1900. The English engineer William Duddell discovered how to make a resonant circuit using a carbon arc lamp.
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Kliegl Brothers logo from the 1922 catalog A Klieg light is an intense carbon arc lamp especially used in filmmaking. It is named after inventor John Kliegl and his brother Anton Kliegl. Klieg lights usually have a Fresnel lens with a spherical reflector or an ellipsoidal reflector with a lens train containing two plano-convex lenses or a single step lens.
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Limelight illumination was replaced by the electrically powered carbon arc lamp, and with the arrival of sound electric motors were installed to drive projectors (a more constant speed was required for sound playback than could be achieved by hand cranking). The operation and basic maintenance of audio equipment also became part of the projectionist's job following the introduction of sound.
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Carbon arc lamp spots were common until the 1990s, using the arc between carbon rods as their light source. These follow spots required special installations that include high volume ventilation due to the hazardous fumes produced by the carbon arc. The current generation, xenon, has extremely high internal pressure in the lamp and thus has its own safety concerns. Followspots contain a variety of operator-controlled optical mechanisms.
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In 2013, movie studios announced that they would be switching from 35 millimeter films to digital distribution –exclusively – by the end of the year. The average cost for an outdoor or single-screen theater to convert to digital projection is approximately $75,000. As of 2013, Cumberland Drive-In was using the same movie projector it used in 1952. The only major change is that in 2003 the lamp houses were changed from carbon arc lamp to powerful light bulbs.
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A discharge lamp has a glass or silica envelope containing two metal electrodes separated by a gas. Gases used include, neon, argon, xenon, sodium, metal halide, and mercury. The core operating principle is much the same as the carbon arc lamp, but the term "arc lamp" normally refers to carbon arc lamps, with more modern types of gas discharge lamp normally called discharge lamps. With some discharge lamps, very high voltage is used to strike the arc.
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Basically, sheets of clear polyester were coated with UV-sensitive pigmented emulsions in the four process colors, cyan, magenta, yellow and black. Later, spot colors were created (Color Key Custom Colors). The sheets were exposed to the artwork via a carbon arc lamp, washed with water and process chemicals, and then dried. As of 2010, overlay proofs are still created, for example for small single-drum presses where each color has to be a separate run.
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While there was no way to control the gas lights, this was soon to change as well. In Britain, theatres in London developed limelight for the stage in the late 1830s. In Paris, the electric carbon arc lamp first came into use in the 1840s. Both of these types of lighting were able to be hand-operated and could be focused by means of an attached lens, thus giving the theatre an ability to focus light on particular performers for the first time.
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Where the need for lighting was mobile, as for the construction of railways or canals, the Wells light had a clear advantage. Secondly, although the carbon arc lamp was bright, and relatively economical for the illumination produced, individual lamps were expensive and complicated, although powerful. This encouraged their use as the minimum number of large lamps to cover an entire work site. As the arc lamp also has a very small source of light, this gave a particularly harsh lighting.
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Yablochkov's demonstration of his brilliant arc lights at the 1878 Paris Exposition along the Avenue de l'Opéra triggered a steep sell off of gas utility stocks. Sir Humphry Davy invented the carbon arc lamp in 1802 upon discovering that electricity could produce a light arc with carbon electrodes. However, it was not used to any great extent until a practical means of generating electricity was developed. Carbon arc lamps were started by making contact between two carbon electrodes, which were then separated to within a narrow gap.
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In 1888 a carbon arc lamp was installed, linked to a powerful set of De Méritens magneto-electric machines, powered by three Robey non-condensing compound steam engines. (St Catherine's was the last English lighthouse to be provided with an arc lamp). A new optic was also provided (a second-order 16-sided revolving dioptric lens array by Chance & co.) which showed a five-second flash every thirty seconds. As well as a new Engine House, more cottages were built, to accommodate the additional staff required to operate the generating plant.
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Soon afterwards an underwater bell was set up two miles south of the Lizard, operated by an electric striker controlled from the lighthouse via a submarine cable. A carbon arc lamp continued to provide the light source until it was superseded in 1926 by an electric filament lamp,Plaque on magneto machine which enabled a reduction in the number of personnel at the lighthouse from five to three.'Lighthouses' in Encyclopaedia Britannica, 1961 edition, volume 14. The engines and magneto generators continued in daily use until 1950, when the lighthouse was connected to mains electricity.
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Variations and alternatives were touted from time to time and a few found a measure of success, especially for amateur use. In 1905, one French photographer was using intense non-explosive flashes produced by a special mechanized carbon arc lamp to photograph subjects in his studio, but more portable and less expensive devices prevailed. On through the 1920s, flash photography normally meant a professional photographer sprinkling powder into the trough of a T-shaped flash lamp, holding it aloft, then triggering a brief and (usually) harmless bit of pyrotechnics.
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The technology was the predominant form of light source in lighthouses from the 1900s through the 1960s, when electric lighting had become dominant. The first electrically illuminated lighthouse was the tower at Dungeness, Kent in 1862. It was powered by a large carbon arc lamp, although it was later converted back to oil, as the arc lamps were difficult to operate (needing twice the number of keepers) and were not as cost-effective as oil lamps. South Foreland Lighthouse was the first tower to successfully use an electric light in 1875.
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Camp Bouse was home to a secret program to see if a very bright arc lamp could be used to temporary blind the enemy in battle at night. The Desert Training Center was built to prepare troops to do battle in North Africa to fight the Nazis during World War 2. When completed the camp had shower buildings, latrines, wooden tent frames, and a 500,000 gallon water reservoir. The top secret weapon was a 13 million candlepower carbon arc lamp mounted on US Medium Tank M3Canal Defence Light (CDL).
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Sunlamp in the Netherlands, 1930 In 1890 the Danish physician Niels Ryberg Finsen developed a carbon arc lamp ("Finsen's light" or a "Finsen lamp") that produced ultraviolet radiation for use in skin therapy, including to treat lupus vulgaris. He won the 1903 Nobel Prize in Physiology or Medicine for his work. Until the late 19th century in Europe and the United States, pale skin was a symbol of high social class among white people. Victorian women would carry parasols and wear wide-brimmed hats and gloves; their homes featured heavy curtains that kept out the sun.
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The hundred and forty stagehands supposedly employed on this production were described by the Literary Gazette as "unseen ... but alas never unheard". Hans Christian Andersen also saw this production and described Ariel as "isolated by the electric ray", referring to the effect of a carbon arc lamp directed at the actress playing the role. The next generation of producers, which included William Poel and Harley Granville-Barker, returned to a leaner and more text-based style. In the late 19th and early 20th centuries, Caliban, not Prospero, was perceived as the star act of The Tempest, and was the role which the actor-managers chose for themselves.
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He could use this to send simple Morse signals to the generator operator, requesting, for example, more or less power. The searchlight included a sophisticated system to control the carbon arc lamp, extending the carbon electrodes to keep a constant arc distance as the ends of the electrodes burned away. The 8 kilowatt, direct current generator that powered the searchlight was driven by a six-cylinder, BMW engine, of a type used in pre-war cars. Typical tactics were to sweep the search light in an S-shaped pattern along the targets' expected course with the beam dispersed, once the target was detected, it was then tracked using the focused beam.
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Yablochkov's arc lamp on the Avenue de l'Opera in Paris (1878), the first form of electric street lighting Heritage lamp post in the City Botanic Gardens, Brisbane The first electric street lighting employed arc lamps, initially the 'Electric candle', 'Jablotchkoff candle' or 'Yablochkov candle' developed by a Russian, Pavel Yablochkov, in 1875. This was a carbon arc lamp employing alternating current, which ensured that both electrodes were consumed at equal rates. In 1876, the common council of the City of Los Angeles ordered four arc lights installed in various places in the fledgling town for street lighting.William H. Workman, The City That Grew (1929) Mirror-Press, Los Angeles, p.
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On December 27, 1902, Kliegl married Leopoldine Helfrich. The marriage remained childless. In 1911 Kliegl invented the carbon arc lamp still known as Klieg light, which produced double the brightness with the same energy needs as contemporary lamps of that time, and was specifically used for stage lighting and filming. In the silent film era he developed many new special effects for movies such as Ben Hur and Wizard of Oz. Kliegl gave generous donations to his home town of Bad Kissingen – the Kliegl children's park, the Anton Kliegl Elementary School, feeding the poor, a nursery, a children's recreation center, and the interior of the council hall in the Old Town Hall benefited from his generosity.
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An arc lamp or arc light is a lamp that produces light by an electric arc (also called a voltaic arc). The carbon arc light, which consists of an arc between carbon electrodes in air, invented by Humphry Davy in the first decade of the 1800s, was the first practical electric light. It was widely used starting in the 1870s for street and large building lighting until it was superseded by the incandescent light in the early 20th century. It continued in use in more specialized applications where a high intensity point light source was needed, such as searchlights and movie projectors until after World War II. The carbon arc lamp is now obsolete for most of these purposes, but it is still used as a source of high intensity ultraviolet light.
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In the late nineteenth century. Finsen successfully demonstrated phototherapy by employing heat-filtered light from a carbon-arc lamp (the "Finsen lamp") in the treatment of a tubercular condition of the skin known as lupus vulgaris, for which he won the 1903 Nobel Prize in Physiology or Medicine. In 1913 another German scientist, Meyer-Betz, described the major stumbling block of photodynamic therapy. After injecting himself with haematoporphyrin (Hp, a photosensitiser), he swiftly experienced a general skin sensitivity upon exposure to sunlight—a recurrent problem with many photosensitisers. The first evidence that agents, photosensitive synthetic dyes, in combination with a light source and oxygen could have potential therapeutic effect was made at the turn of the 20th century in the laboratory of Hermann von Tappeiner in Munich, Germany.
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The late 1870s and early 1880s saw electricity starting to be generated at power stations. These were initially set up to power arc lighting (a popular type of street lighting) running on very high voltage (usually higher than 3000 volt) direct current or alternating current.The First Form of Electric Light History of the Carbon Arc Lamp (1800–1980s) This was followed by the wide spread use of low voltage direct current for indoor electric lighting in business and homes after inventor Thomas Edison launched his incandescent bulb based electric "utility" in 1882. Because of the significant advantages of alternating current over direct current in using transformers to raise and lower voltages to allow much longer transmission distances, direct current was replaced over the next few decades by alternating current in power delivery.
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A small motor-generator set A motor-generator set, or the similar rotary converter, is not strictly a rectifier as it does not actually rectify current, but rather generates DC from an AC source. In an "M-G set", the shaft of an AC motor is mechanically coupled to that of a DC generator. The DC generator produces multiphase alternating currents in its armature windings, which a commutator on the armature shaft converts into a direct current output; or a homopolar generator produces a direct current without the need for a commutator. M-G sets are useful for producing DC for railway traction motors, industrial motors and other high-current applications, and were common in many high-power D.C. uses (for example, carbon-arc lamp projectors for outdoor theaters) before high-power semiconductors became widely available.
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Nevertheless, the Elder Brethren maintained that electricity 'may still become a most valuable element in lighthouse illumination in some few special cases; but to enable it to become so, or to give a fair estimate of its powers, it must be exhibited under entirely changed conditions from those which now exist'. Lessons learned from the difficulties with electric light at Dungeness led to far more reliable systems being installed in 1871 at Souter Point (the first purpose-built electrically- lit lighthouse) and in 1872 at South Foreland. Costs were also progressively reduced: the operating cost per unit of light of the electric system installed at the Lizard Lighthouses in 1874 was one ninth that of Dungeness. The carbon arc lamp remained in use at Dungeness until 1 October 1875,London Gazette, Issue 24251, Page 4726, 5 October 1875.
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Extremely bright arc lights were too bright, and with the high voltages and sparking/fire hazard, too dangerous to use indoors.The First Form of Electric Light History of the Carbon Arc Lamp (1800 – 1980s) In 1878 inventor Thomas Edison saw a market for a system that could bring electric lighting directly into a customer's business or home, a niche not served by arc lighting systems.Howard B. Rockman, Intellectual Property Law for Engineers and Scientists, John Wiley – 2004, page 131 After devising a commercially viable incandescent light bulb in 1879, Edison went on to develop the first large scale investor-owned electric illumination "utility" in lower Manhattan, eventually serving one square mile with 6 "jumbo dynamos" housed at Pearl Street Station.Ahmad Faruqui, Kelly Eakin, Pricing in Competitive Electricity Markets, Springer Science & Business Media – 2000, page 67 When service began in September 1882, there were 85 customers with 400 light bulbs.
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Initially, the Super Trouper utilized a high-intensity carbon arc lamp, which produced an almost snow white spot that set the performer apart from ambient stage lighting. In the 1980s and as carbon arc lamps fell into decreasing use, the spotlight began to employ a high-intensity xenon lamp as its light source. Because of the Super Trouper's brilliant light field, many performers specify it in their technical riders. A large segment of U.S. entertainment venues, including proscenium theaters and arenas, continue to utilize Strong Super Troupers as their primary follow spotlights and it remains the "standard" that all other spotlights are generally judged against. The Super Trouper line of xenon follow spots is inclusive of four production models: Super Trouper Long Throw, Super Trouper Short Throw, Super Trouper Medium Throw, and Super Trouper II. Each model is available in either a 1600 watt or a 2000 watt variety.
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