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115-579: All enlargers consist of a light source, normally an incandescent light bulb shining though a condenser or translucent screen to provide even illumination, a holder for the negative or transparency, and a specialized lens for projection, though some, such as the Rapid Rectilinear or Aplanat could be used in both camera and enlarger. Enlarger lenses, like the dialyte construction, are generally symmetrical in design or nearly so, optimised for sharp focus at 2x to 10x magnification. The light passes through

230-424: A billboard to be viewed no closer than 5 metres. Since the inverse square law applies to illumination intensity at increasing distance, enlargement beyond a certain size becomes impractical, requiring extended exposure times and dependent on the extent to which dampening of enlarger supports may eliminate vibration causing blur in the resulting print. The claim for the biggest analogue enlargement ever made from

345-417: A contact print —by placing the negative in contact with the albumen paper under glass and exposing the sandwiched materials to a light source. No enlarger was required. Nevertheless, the development of the solar camera enabled enlargements of cartes up to life-size, often hand-coloured and retouched so that they rivalled the painted portrait, and could be framed and displayed. Prominent London photographer

460-429: A film holder, which holds the exposed and developed photographic negative or transparency. Prints made with an enlarger are called enlargements . Typically, enlargers are used in a darkroom , an enclosed space from which extraneous light may be excluded; some commercial enlargers have an integral dark box so that they can be used in a light-filled room. Josef Maria Eder , in his History of Photography attributes

575-407: A phase-out of incandescent light bulbs to reduce energy consumption. Historians Robert Friedel and Paul Israel list inventors of incandescent lamps prior to Joseph Swan and Thomas Edison of General Electric . They conclude that Edison's version was the first practical implementation, able to outstrip the others because of a combination of four factors: an effective incandescent material;

690-434: A vacuum higher than other implementations which was achieved through the use of a Sprengel pump ; a high resistance that made power distribution from a centralized source economically viable, and the development of the associated components required for a large-scale lighting system. Historian Thomas Hughes has attributed Edison's success to his development of an entire, integrated system of electric lighting. The lamp

805-565: A 35mm photograph is that for and Ernst Haas wildlife picture taken in Kenya in 1970. It required a 5-hour exposure using the Kodak Colorama process, for a giant transparency. The 508-times enlargement consisted of 20 vertical panels of 3 feet width and 18 feet height (91.4 x 548.6 cm) for a total size of 18 x 60 feet (5.48 m x 18.28 m). Displayed at Grand Central Station in New York city in 1977, it

920-428: A Canadian patent was filed by Henry Woodward and Mathew Evans for a lamp consisting of carbon rods mounted in a nitrogen-filled glass cylinder. They were unsuccessful at commercializing their lamp, and sold rights to their patent to Thomas Edison in 1879. (Edison needed ownership of the novel claim of lamps connected in a parallel circuit.) The government of Canada maintains that it is Woodward and Evans who invented

1035-488: A Hungarian patent (No. 34541) for a tungsten filament lamp that lasted longer and gave brighter light than the carbon filament. Tungsten filament lamps were first marketed by the Hungarian company Tungsram in 1904. This type is often called Tungsram-bulbs in many European countries. Filling a bulb with an inert gas such as argon or nitrogen slows down the evaporation of the tungsten filament compared to operating it in

1150-538: A base neutral filtration from the negative rebate. The enlarger's lamp or shutter mechanism is controlled either by an electronic timer, or by the operator – who marks time with a clock, metronome or simply by counting seconds – shuttering or turning off the lamp when the exposure is complete. The exposed paper can be processed immediately or placed in a light-tight container for later processing. Digitally controlled commercial enlargers typically adjust exposure in steps known as printer points ; twelve printer points makes

1265-469: A broader array of light sources. The spectrum of light produced by an incandescent lamp closely approximates that of a black body radiator at the same temperature. The basis for light sources used as the standard for color perception is a tungsten incandescent lamp operating at a defined temperature. Carte de visite The carte de visite ( French: [kaʁt də vizit] , English: ' visiting card ', abbr. 'CdV', pl. cartes de visite )

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1380-508: A carbon conductor, and platinum lead-in wires. This bulb lasted about 40 hours. Swan then turned his attention to producing a better carbon filament and the means of attaching its ends. He devised a method of treating cotton to produce 'parchmentised thread' in the early 1880s and obtained British Patent 4933 that same year. From this year he began installing light bulbs in homes and landmarks in England. His house, Underhill, Low Fell, Gateshead ,

1495-465: A carbonized bamboo filament could last more than 1200 hours. In 1880, the Oregon Railroad and Navigation Company steamer, Columbia , became the first application for Edison's incandescent electric lamps (it was also the first ship to use a dynamo ). Albon Man, a New York lawyer, started Electro-Dynamic Light Company in 1878 to exploit his patents and those of William Sawyer . Weeks later

1610-466: A coiled platinum filament in a vacuum tube and passed an electric current through it. The design was based on the concept that the high melting point of platinum would allow it to operate at high temperatures and that the evacuated chamber would contain fewer gas molecules to react with the platinum, improving its longevity. Although a workable design, the cost of the platinum made it impractical for commercial use. In 1841, Frederick de Moleyns of England

1725-477: A color print or one on variable-contrast black-and-white paper. A series of test strips, and/or a stepped series of exposures made on the one sheet of paper, are undertaken to determine ideal exposure, and then contrast or colour filtration. Alternatively a custom incident light meter ( densitometer or 'colour-' or 'darkroom analyser') may be used in setting exposure once the degree of enlargement has been decided, and in colour printing may also be used to establish

1840-496: A constant electric light at a public meeting in Dundee, Scotland . He stated that he could "read a book at a distance of one and a half feet". However he did not develop the electric light any further. In 1838, Belgian lithographer Marcellin Jobard invented an incandescent light bulb with a vacuum atmosphere using a carbon filament. In 1840, British scientist Warren De la Rue enclosed

1955-581: A cook. Amongst other applications in answer to his advertisement was one from a "young lady" of the profession, enclosing her carte de visite and stating her salary." Now regarded as an early manifestation of "social media", cartes-de-visite were an adjunct to letter-writing; unlike the fragile daguerreotypes which preceded them and which also were used predominantly for portraits, they could be posted in regular manufactured envelopes which had become available only ten years before. For example, as Belknap notes, Charles Darwin exchanged in his correspondence

2070-452: A factor of two change in exposure. If a greater or lesser enlargement from the same negative is then required, a calculator – analogue, digital or in app format – may be used to quickly extrapolate from the original settings the exposure without the need for labour-intensive re-testing. After exposure, photographic paper is developed, fixed, washed and dried using the gelatin silver or C-print process. Automated photo print machines have

2185-669: A fixed size. Some cameras were made convertible to use in a similar manner. In the 1870s hand-coloured enlargements from carte-de-visite prints and daguerreotypes as well as existing negatives were offered for sale in London, England for two shillings for an A4 print, and three pounds for a life size bust. R. L. Elliot & Company, of King's Road could print up to 25" x 20" from quarter plate negatives in 1878 using limelight , as suggested by John Benjamin Dancer . Fast bromide and chloride printing papers largely superseded albumen emulsions in

2300-475: A glass receiver, hermetically sealed, and filled with nitrogen, electrically arranged so that the current could be passed to the second carbon when the first had been consumed. Later he lived in the US, changed his name to Alexander de Lodyguine and applied for and obtained patents for incandescent lamps having chromium , iridium , rhodium , ruthenium , osmium , molybdenum and tungsten filaments. On 24 July 1874,

2415-448: A lamp with inert gas instead of a vacuum resulted in twice the luminous efficacy and reduced bulb blackening. In 1917, Burnie Lee Benbow was granted a patent for the coiled coil filament , in which a coiled filament is then itself wrapped into a coil by use of a mandrel . In 1921, Junichi Miura created the first double-coil bulb using a coiled coil tungsten filament while working for Hakunetsusha (a predecessor of Toshiba ). At

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2530-407: A large number; 132 photographic portraits before 1882. Their value to him was demonstrated in his response to their gift of an album by Dutch naturalists containing 217 carte de visites; "...for the few remaining years of my life, whenever I want cheering, I will look at the portraits of my distinguish co-workers in the field of science, and remember their generous sympathy. When I die the album will be

2645-405: A lens, typically fitted with an adjustable aperture marked with f/ stops, onto a flat surface bearing the sensitized photographic paper . By adjusting the ratio of distance from film to lens to the distance from lens to paper, various degrees of enlargement may be obtained, with the physical enlargement ratio limited only by the structure of the enlarger and the size of the paper. As the image size

2760-406: A lower resistivity than carbon, the tantalum lamp filament was quite long and required multiple internal supports. The metal filament gradually shortened in use; the filaments were installed with large slack loops. Lamps used for several hundred hours became quite fragile. Metal filaments had the property of breaking and re-welding, though this would usually decrease resistance and shorten the life of

2875-455: A magnificent device, consisting of 4 identical double lenses mounted on a double frame camera built by M. Besson. This device, in a single operation, provides a plate on which 8 copies of the same image appear with perfect clarity. It seems that in the big cities, such as Paris, London, Berlin, St. Petersburg, these cartes de visite are widely used, so the device we saw at M. Hermagis' enjoys considerable success. Cartes de visite were made using

2990-481: A meeting of the Literary and Philosophical Society of Newcastle upon Tyne on 3 February 1879. These lamps used a carbon rod from an arc lamp rather than a slender filament. Thus they had low resistance and required very large conductors to supply the necessary current, so they were not commercially practical, although they did furnish a demonstration of the possibilities of incandescent lighting with relatively high vacuum,

3105-422: A portrait of himself that he found unflattering and tried to prevent further sales. Women in particular found themselves vulnerable to having their pictures purchased by 'cads' who would boast that she had gifted them the image and, given the moral standards of the day, discovered their reputations 'tarnished'. Photographers were in effect publishers, distributing thousands of copies of their images. They would pay

3220-528: A present from H.R.H. Prince Alfred in February 1861. The carte de visite was introduced in New York, probably by Charles DeForest Fredricks , late in the summer of 1859 and proved immediately popular in the era of the Civil War . During the war years, photography studios across the country generated hundreds of thousands of carte-de-visite portraits in decorative pressed-paper and tooled-leather albums prized by

3335-694: A process of introducing red phosphorus as the so-called getter inside the bulb ), which allowed obtaining economic bulbs lasting 800 hours; his patent was acquired by Edison in 1898. In 1897, German physicist and chemist Walther Nernst developed the Nernst lamp , a form of incandescent lamp that used a ceramic globar and did not require enclosure in a vacuum or inert gas. Twice as efficient as carbon filament lamps, Nernst lamps were briefly popular until overtaken by lamps using metal filaments. US575002A patent on 01.Dec.1897 to Alexander Lodyguine (Lodygin, Russia) describes filament made of rare metals, amongst them

3450-399: A rigid stand. This method will probably contribute very much to the practice of the art." In March 1843 Americans Wolcott and Johnson patented a means of copying and enlarging daguerreotypes. In June 1843, Henry Fox Talbot in his patent for an enlarger for his calotype process which produced a paper negative , mentions that using lenses it is possible to produce a large negative from

3565-402: A ruling 8 October 1883, that Edison's patents were based on the prior art of William Sawyer and were invalid. Litigation continued for a number of years. Eventually on 6 October 1889, a judge ruled that Edison's electric light improvement claim for "a filament of carbon of high resistance" was valid. The main difficulty with evacuating the lamps was moisture inside the bulb, which split when

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3680-500: A series of portraits which had been previously taken of the Royal family and of several other illustrious personages who have the honour of being intimate friends of her Majesty. These charming portraits are of miniature size; some of them are mounted on cards, and opposite to that of the Queen in the catalogue we find it described as a carte de visite . A complete series is placed upon a screen, in

3795-560: A single print would cost 50 to 100 francs, so that portraits were suddenly available at a cost that the lower middle classes could afford. The new invention was so popular that "cardomania" spread quickly throughout Europe and then to the rest of the world. In England John Jabez Edwin Mayall in Regent Street announced in August 1860 that he had; ...just received the Royal permission to publish

3910-447: A smaller one, so having made such enlargements has a priority claim to be the inventor of a system for making an enlarged print from a negative, though it did not go into production and was not practical given the lengthy exposures required. In 1848, Talbot recommended to fellow photographer Thomas Malon the enlarging camera made by Thomas Ross of lens manufacturers Ross, Andrew & Thomas. The advent of collodion negatives on glass in

4025-421: A source is defined as the ratio of its luminous efficacy to the maximum possible luminous efficacy, which is 683 lm/W. An ideal white light source could produce about 250 lumens per watt, corresponding to a luminous efficiency of 37%. For a given quantity of light, an incandescent light bulb consumes more power and emits more heat than most other types of electric light. In buildings where air conditioning

4140-518: A successful version of this the first synthetic filament. The light bulb invented by Cruto lasted five hundred hours as opposed to the forty of Edison's original version. In 1882 Munich Electrical Exhibition in Bavaria, Germany Cruto's lamp was more efficient than the Edison's one and produced a better, white light. In 1893, Heinrich Göbel claimed he had designed the first incandescent light bulb in 1854, with

4255-481: A symbol of the lost colonial Lima. The tapada – meaning “covered” or “veiled” - refers to a type of traditional dress. The costume consisted of the manto (“shawl”) and saya (a close-fitting pleated skirt), both in conservative dark colors. The manto covered the head and was drawn to completely cover the face, leaving a triangular window exposing a single eye. In Australia Manchester -born William Davies began his photographic career with Walter Woodbury (inventor of

4370-480: A system of lighting . In 1761, Ebenezer Kinnersley demonstrated heating a wire to incandescence . However such wires tended to melt or oxidize very rapidly (burn) in the presence of air. Limelight became a popular form of stage lighting in the early 19th century, by heating a piece of calcium oxide to incandescence with an oxyhydrogen torch . In 1802, Humphry Davy used what he described as "a battery of immense size", consisting of 2,000 cells housed in

4485-472: A thin carbonized bamboo filament of high resistance, platinum lead-in wires in an all-glass envelope, and a high vacuum. Judges of four courts raised doubts about the alleged Göbel anticipation , but there was never a decision in a final hearing due to the expiration of Edison's patent. Research work published in 2007 concluded that the story of the Göbel lamps in the 1850s is fictitious. Joseph Swan (1828–1914)

4600-453: A vacuum. This allows for greater temperatures and therefore greater efficacy with less reduction in filament life. In 1906, William D. Coolidge developed a method of making "ductile tungsten" from sintered tungsten which could be made into filaments while working for General Electric Company . By 1911 General Electric had begun selling incandescent light bulbs with ductile tungsten wire. In 1913, Irving Langmuir found that filling

4715-473: A well-known sitter in return for the right to publish their photograph; “the person photographed was offered a flat fee ranging from 25 to 1000 dollars, depending upon notoriety, or a royalty based upon the number of copies sold”. Those whose faces attracted sales, or who already had some incidental notoriety, earned further celebrity and might thus trade on it. However, copyright laws enacted contemporaneously in England protected photographers' rights over those of

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4830-566: A wide range of sizes, light output, and voltage ratings, from 1.5 volts to about 300 volts. They require no external regulating equipment , have low manufacturing costs , and work equally well on either alternating current or direct current . As a result, the incandescent bulb became widely used in household and commercial lighting, for portable lighting such as table lamps, car headlamps , and flashlights , and for decorative and advertising lighting. Incandescent bulbs are much less efficient than other types of electric lighting. Less than 5% of

4945-418: Is diffused by translucent glass or plastic, providing even illumination for the film. Diffusion enlargers produce an image of the same contrast as a contact print from the negative. Cold light or cold cathode enlargers employ diffusion enlarger heads with a coiled Fluorescent lamp tube rather than a conventional light bulb. Their light is blue-rich, in an area of the spectrum to which silver gelatin paper

5060-458: Is a variation of the condenser enlarger designed to cut light diffusion above the negative. Contrast is enhanced and grain in the resultant print is sharper than with a conventional enlarger, and the transition from light to dark at the edge of the shadow areas is dramatic. An unfrosted clear lamp with a tiny filament is used without diffusers. As the illuminant is narrow, the lamp must be precisely positioned both vertically and horizontally, because

5175-413: Is an electric light with a filament that is heated until it glows . The filament is enclosed in a glass bulb that is either evacuated or filled with inert gas to protect the filament from oxidation . Electric current is supplied to the filament by terminals or wires embedded in the glass. A bulb socket provides mechanical support and electrical connections. Incandescent bulbs are manufactured in

5290-423: Is changed it is also necessary to change the focus of the lens. Some enlargers, such as Leica's "Autofocus" enlargers, perform this automatically. An easel is used to hold the paper perfectly flat. Some easels are designed with adjustable overlapping flat steel "blades" to crop the image on the paper to the desired size while keeping an unexposed white border about the image. Paper is sometimes placed directly on

5405-422: Is sensitive, and therefore exposure is shorter compared to other light sources, ideal for making large mural prints which require extended exposure, and heat is reduced which is beneficial in avoiding buckling or 'popping' of negatives, and also are Newton's rings ' where a glass negative carrier is used. They produce a softer (less contrast) print. Color enlargers typically contain an adjustable filter mechanism –

5520-431: Is then rendered by passing light through the negative and a built-in computer-controlled enlarger optically projects this image to the paper for final exposure. As a byproduct of the process a compact disc recording may be made of the digital images, although a subsequent print made from these may be inferior to an image made from the negative due to digitization noise and lack of dynamic range which are characteristics of

5635-402: Is used when high quality, large format enlargements are required such as when photographs are taken from aircraft for mapping and taxation purposes. The parts of the enlarger include baseboard, enlarger head, elevation knob, filter holder, negative carrier, glass plate, focus knob, girder scale, timer, bellows, and housing lift. The image from the negative or transparency is projected through

5750-411: Is used, incandescent lamps' heat output increases load on the air conditioning system. While heat from lights will reduce the need to run a building's heating system, the latter can usually produce the same amount of heat at lower cost than incandescent lights. The chart below lists the luminous efficacy and efficiency for several types of incandescent bulb. A longer chart in luminous efficacy compares

5865-464: The 1862 World Fair , which were praised as 'magnificent' and 'without distortion'. The carte de visite was slow to gain widespread use until 1859, when Disdéri published Emperor Napoleon III 's photos in this format. This made the format an overnight success; as Disdéri was to boast; "Everyone knows how I suddenly became popular by inventing the carte de visite which I had patented in 1854." He charged 20 francs for twelve photographs when previously

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5980-593: The Easy-Bake Oven toy. Quartz envelope halogen infrared heaters are used for industrial processes such as paint curing and space heating. Incandescent bulbs typically have shorter lifetimes compared to other types of lighting; around 1,000 hours for home light bulbs versus typically 10,000 hours for compact fluorescents and 20,000–30,000 hours for lighting LEDs. Most incandescent bulbs can be replaced by fluorescent lamps , high-intensity discharge lamps , and light-emitting diode lamps (LED). Some governments have begun

6095-588: The Edison and Swan United Electric Company (later known as Ediswan, and ultimately incorporated into Thorn Lighting Ltd ). Edison was initially against this combination, but Edison was eventually forced to cooperate and the merger was made. Eventually, Edison acquired all of Swan's interest in the company. Swan sold his US patent rights to the Brush Electric Company in June 1882. The United States Patent Office gave

6210-746: The United States Electric Lighting Company was organized. This company did not make their first commercial installation of incandescent lamps until the fall of 1880, at the Mercantile Safe Deposit Company in New York City, about six months after the Edison incandescent lamps had been installed on the Columbia . Hiram S. Maxim was the chief engineer at the US Electric Lighting Co. After the great success in

6325-623: The Woodburytype ) and established several studios in Melbourne from 1858. William Davies and Co at 98 Bourke St ., being opposite the Theatre Royal , sold cartes de visite of famous actors, actresses and opera singers. The company also specialised in carte de visite portraits of Protestant clergymen posed as if writing their sermons. The Albury Banner and Wodonga Express of May 1863 finds it noteworthy that "a gentleman had occasion to advertise for

6440-498: The anthropometric genre—standardised poses of naked or semi-naked bodies—of slaves and freed people. As such they were not portraits since they lack any contextual information, or the name of the person; they illustrate contemporaneous biological theories of race being disseminated in Brazil, though not yet widely accepted. Stahl's were shown at the second National Exhibition in 1866. Such cartes de visites were circulated in Brazil between

6555-570: The electric arc , by passing high current between two pieces of charcoal. For the next 40 years much research was given to turning the carbon arc lamp into a practical means of lighting. The carbon arc itself was dim and violet in color, emitting most of its energy in the ultraviolet, but the positive electrode was heated to just below the melting point of carbon and glowed very brightly with incandescence very close to that of sunlight. Arc lamps burned up their carbon rods very rapidly, expelled dangerous carbon monoxide, and tended to produce outputs in

6670-476: The film plane , to produce a photographic enlargement from a digital file. Most modern enlargers are vertically mounted with the lens pointing downward. Moving the head on the column up or down changes the size of the image projected onto the enlarger's base, or a work table if the unit is mounted to the wall. A horizontal enlarger consists of a trestle, with the head mounted on crossbars between two or more posts for extra stability. A horizontal enlarger structure

6785-454: The portrait miniature and its cheaper versions, the silhouette and the physionotrace . However its technologies were limited; a single copy was made in the camera could be reproduced only by copying the original onto another plate. The carte-de-visite provided a wet collodion negative from which could be made multiple prints, in a standardised format, with cheaper materials, thus permitting production on an industrial scale. Consequently it

6900-701: The "professors" of New York, Boston, and Philadelphia send their representatives to pick up whatever is left, and to follow the camps as well as they can. Major studios producing cartes de visite included Brady & Company , Samuel Masury , J. Hall & Company, and N A. & R.A. Moore. Americans, as with citizens of other countries, were also not only buying photographs of themselves, but also collecting photographs of celebrities. Portuguese-born Cristiano Júnior in Argentina, and German-born Alberto Henschel and Italian-born photographer Auguste Stahl in Brazil, made carte de visite pictures of “racial types” in

7015-489: The 1850s made enlargement more practical. Achille Quinet's invention of 1852 used artificial light, but was inefficient, requiring very extended exposures. David Acheson Woodward's 1857 'solar enlarging camera' addressed that problem by tapping the brightest light-source then available – the Sun – with mirrors and a condenser. Solar cameras , introduced in the late 1850s, and ancestors of the darkroom enlarger, were necessary because of

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7130-603: The 1860s and 1880s, as were caste-paintings in late 18th-century Spanish America, but Stahl's were exhibited only once as photographs. Even though praised for their “exceptionally high quality” by the painter Victor Meirelles they were excluded from the Brazilian representation at the London Exhibition of 1862 , but at subsequent world's fairs they were present as engraved copies illustrating Swiss-American naturalist Louis Agassiz ’ A Journey in Brazil (1868) circulated at

7245-573: The 1880s. A condenser enlarger consists of a light source, a condensing lens , a holder for the negative and a projecting lens. The condenser provides even illumination to the negative beneath it. Condenser enlargers produce higher contrast than diffusion enlargers because light is scattered from its path by the negative's image silver; this is called the Callier effect . The condenser's increased contrast emphasises any negative defects, such as dirt and scratches, and image grain. A point source enlarger

7360-724: The French-born Antoine Claudet lectured on the technology to the British Association in Oxford in June 1860, and in 1862 presented "On the means of following the small divisions of the scale regulating the distances and enlargement in the solar camera" at the British Association for the Advancement of Science in October. Earlier that year he exhibited a number of life-size portrait enlargements from carte de visite negatives at

7475-806: The United States, the incandescent light bulb patented by Edison also began to gain widespread popularity in Europe as well; among other places, the first Edison light bulbs in the Nordic countries were installed at the weaving hall of the Finlayson 's textile factory in Tampere, Finland in March 1882. Lewis Latimer , employed at the time by Edison, developed an improved method of heat-treating carbon filaments which reduced breakage and allowed them to be molded into novel shapes, such as

7590-612: The Vienna Universal Exhibition (1873) and the Philadelphia Centennial Exhibition (1876). From 1854 through the end of the century, the Peruvian photographic firm C. Clavijo produced carte de visite . This unique calling card depicts an unidentified woman as a tapada. The tapada was the most widespread “tipo de antano” or a sentimental, nostalgic stereotype of traditional stock characters from times gone by,

7705-461: The basement of the Royal Institution of Great Britain, to create an incandescent light by passing the current through a thin strip of platinum , chosen because the metal had an extremely high melting point . It was not bright enough nor did it last long enough to be practical, but it was the precedent behind the efforts of scores of experimenters over the next 75 years. Davy also demonstrated

7820-478: The centre of which are large portraits of his Royal Highness the Prince of Wales in military uniform, and his Royal Highness Prince Alfred in the dress of a midshipman in the Royal navy. Besides the single.figure portraits of the Royal family, there are several most delightful groups of them variously arranged [...] These portraits having been entirely divested of all appearance of Royal state, possess an air of novelty, and

7935-507: The characteristic "M" shape of Maxim filaments. On 17 January 1882, Latimer received a patent for the "Process of Manufacturing Carbons", an improved method for the production of light bulb filaments, which was purchased by the United States Electric Light Company. Latimer patented other improvements such as a better way of attaching filaments to their wire supports. In Britain, the Edison and Swan companies merged into

8050-542: The cheaper tintypes franchised as the "American Gem," and by " cabinet cards " (the term established in Cabinet painting ), which were also usually albumen prints, but larger, and mounted on cardboard backs measuring 110 mm (4.5 in) by 170 mm (6.5 in). Nevertheless, while larger framed prints became available at photography studios, the two smaller formats were the main trade of professional portrait photographers even between 1888, when George Eastman introduced

8165-588: The color head – between the light source and the negative, enabling the user to adjust the amount of cyan , magenta and yellow light reaching the negative to control color balance . Other models have a drawer where cut filters can be inserted into the light path, synthesize colour by additive mixing of light from colored lamps with adjustable intensity or duty cycle, or expose the receiving medium sequentially using red, green and blue light. Such enlargers can also be used with variable-contrast monochrome papers. Digital enlargers project an image from an LCD screen at

8280-408: The condensers project only that single small filament rather than light that fills the whole housing. However the lens must be kept at full aperture to avoid projecting an image of the light source restricted to the centre of the baseboard, which will cause vignetting and falloff in the print. Exposure is controlled through duration or using a variable transformer. A diffusion enlarger's light source

8395-579: The cost of providing a given quantity of light by a factor of thirty, compared with the cost at introduction of Edison's lighting system. Consumption of incandescent light bulbs grew rapidly in the US. In 1885, an estimated 300,000 general lighting service lamps were sold, all with carbon filaments. When tungsten filaments were introduced, about 50 million lamp sockets existed in the US. In 1914, 88.5 million lamps were used, (only 15% with carbon filaments), and by 1945, annual sales of lamps were 795 million (more than 5 lamps per person per year). Less than 5% of

8510-424: The digitizing process. For better images, the negatives may be reprinted using the same automated machine under operator selection of the print to be made. The practical amount of enlargement (irrespective of the enlarger structure) will depend upon the grain size of the negative, the sharpness (accuracy) of both the camera and projector lenses, blur in the image due to subject motion, focus, and camera shake during

8625-447: The energy they consume is converted into visible light; the rest is lost as heat. The luminous efficacy of a typical incandescent bulb for 120 V operation is 16 lumens per watt (lm/W), compared with 60 lm/W for a compact fluorescent bulb or 100 lm/W for typical white LED lamps . The heat produced by filaments is used in some applications, such as heat lamps in incubators , lava lamps , Edison effect bulbs, and

8740-421: The exposure. The intended viewing distance for the final product is a consideration. For example, an enlargement from a certain negative as a 12 x 18 cm (approx. 5 by 7 inch) print may be sufficient for a scrapbook viewed at 50 cm (20 inches), but insufficiently detailed for an A4 print hung on a hallway wall to be viewed at the same distance, though usable at a larger 120 x 180 cm (ten times larger) on

8855-611: The filament. General Electric bought the rights to use tantalum filaments and produced them in the US until 1913. From 1898 to around 1905, osmium was also used as a filament in lamps made by Carl Auer von Welsbach . The metal was so expensive that used lamps could be returned for partial credit. It could not be made for 110 V or 220 V so several lamps were wired in series for use on standard voltage circuits. These were primarily sold in Europe. On 13 December 1904, Hungarian Sándor Just and Croatian Franjo Hanaman were granted

8970-407: The format and its rapid uptake worldwide were due to their relative cheapness, which made portrait photographs accessible to a broader demographic, and prior to the advent of mechanical reproduction of photographs, led to the publication and collection of portraits of prominent persons. It was the success of the carte de visite that led to photography's institutionalisation. The carte de visite

9085-478: The help of Charles Stearn, an expert on vacuum pumps, in 1878, Swan developed a method of processing that avoided the early bulb blackening. This received a British Patent in 1880. On 18 December 1878, a lamp using a slender carbon rod was shown at a meeting of the Newcastle Chemical Society , and Swan gave a working demonstration at their meeting on 17 January 1879. It was also shown to 700 who attended

9200-420: The illustrious personages being represented as if perfectly unconscious of the photographer's presence, and engaged in their ordinary occupations, seem to afford the public a legitimate peep into the privacy of the Royal apartments, and give a decided charm to this publication [...] purchasers may, while they have the satisfaction of displaying their loyalty, also have the pleasure of selecting those arrangements of

9315-530: The imprimatur of Hofphotograph (court photographer), based on the cartes that each had made of the kaiser, flatteringly posed with his gloved right fist planted powerfully on a table bearing his plumed helmet, and of his family. Millions of his photographs were collected in German family albums. By the late 1850s the carte-de-visite had been taken up in India, particularly among the wealthy of Bombay. Hurrychind Chintamon

9430-518: The inside of lamp bulbs without weakening them. In 1947, he patented a process for coating the inside of lamps with silica . In 1930, Hungarian Imre Bródy filled lamps with krypton gas rather than argon, and designed a process to obtain krypton from air. Production of krypton filled lamps based on his invention started at Ajka in 1937, in a factory co-designed by Polányi and Hungarian-born physicist Egon Orowan . By 1964, improvements in efficiency and production of incandescent lamps had reduced

9545-654: The invention of photographic enlargement to Humphry Davy who realised the idea of using a solar microscope to project images onto sensitised paper. In June 1802, Davy published in the first issue of the Journals of the Royal Institution of Great Britain his An Account of a Method of Copying Paintings upon Glass, and of Making Profiles, by the Agency of Light upon Nitrate of Silver. Invented by T. Wedgwood, Esq. With Observations by H. Davy in which he described their experiments with

9660-415: The lamp was lit, with resulting oxygen attacking the filament. In the 1880s, phosphoric anhydride was used in combination with expensive mercury vacuum pumps . However, about 1893, Italian inventor Arturo Malignani  [ it ] (1865–1939), who lacked these pumps, discovered that phosphorus vapours did the job of chemically binding the remaining amounts of water and oxygen. In 1896 he patented

9775-592: The late Qing Dynasty from c.1870, and was photographer to Governor of Hong Kong Sir Arthur Kennedy KCB and Grand Duke Alexei Alexandrovich of Russia . Other Chinese photo studios producing cartes de visite in the 1890s include those of Kung Tai (公泰照相樓) and Sze Yuen Ming (上洋耀華照相) in Shanghai , and Pun Lun (繽綸) in Hong Kong. Frederick York of Cape Town received the first carte-de-visite camera in South Africa as

9890-468: The length of a light-tight bellows with a geared rack and pinion mechanism. The lens is set to its working aperture. Enlarging lenses have an optimum range of apertures which yield a sharp image from corner to corner, which is 3 f/ stops smaller than the maximum aperture of the lens. For an enlarging lens with a maximum aperture of f/2.8, the optimal aperture would be f/8. The lens is normally set to this aperture and any color filtration dialed in, if making

10005-442: The lightbulb. On 4 March 1880, just five months after Edison's light bulb, Alessandro Cruto created his first incandescent lamp. Cruto produced a filament by deposition of graphite on thin platinum filaments, by heating it with an electric current in the presence of gaseous ethyl alcohol . Heating this platinum at high temperatures leaves behind thin filaments of platinum coated with pure graphite. By September 1881 he had achieved

10120-434: The low light sensitivity of albumen and calotype materials used. A larger version of the 18th century solar microscope , they were first freestanding, a design analogous to picture-taking cameras but with the relative position of negative and lens reversed so that sunlight shone through the glass plate to be projected onto photo-sensitive paper inside the instrument. Mounted on a stand, they could be rotated to continuously face

10235-536: The most precious bequest to my children." However, as a Saturday Review , of 1862 notes; "The demand for photographs is not limited to relations or friends. […] Anyone who has seen you, or has seen anybody that has seen you, or knows anyone that says he has seen a person who thought he had seen you, considers himself entitled to ask you for your photograph." John Ruskin considered a photograph of him taken by William Downey as ʻvisible libelʼ, while Punch illustrator John Tenniel discovered John Watkins selling

10350-534: The museum of the Château de Blois . In 1859, Moses G. Farmer built an electric incandescent light bulb using a platinum filament. Thomas Edison later saw one of these bulbs in a shop in Boston, and asked Farmer for advice on the electric light business. In 1872, Russian Alexander Lodygin invented an incandescent light bulb and obtained a Russian patent in 1874. He used as a burner two carbon rods of diminished section in

10465-463: The photosensitivity of silver nitrate. Eder credits the first mention of enlargements after the announcement of the daguerreotype (unique images on metal plates) to John William Draper who in 1840, wrote prophetically in the American Repository of Arts ; "Exposures are made with a very small camera on very small plates. These are subsequently enlarged to the required size in a larger camera on

10580-585: The portraits to which they may give a preference. The whole series, including the personal friends of her Majesty, amounts to 32 portraits, and are very beautiful specimens of the photographic art. Mayall's publication of a carte-de-visite album of the Royal Family influenced the growing demand from the Victorian public for their own family photographic albums. In Germany, Emperor Wilhelm I encouraged this pictorial culture by investing approximately 120 studios with

10695-412: The power consumed by a typical incandescent light bulb is converted into visible light, with most of the rest being emitted as invisible infrared radiation. Light bulbs are rated by their luminous efficacy , which is the ratio of the amount of visible light emitted ( luminous flux ) to the electrical power consumed. Luminous efficacy is measured in lumens per watt (lm/W). The luminous efficiency of

10810-410: The same basic elements and integrate each of the steps outlined above in a single complex machine under operator and computer control. Rather than project directly from the film negative to the print paper, a digital image may first be captured from the negative. This allows the operator or computer to quickly determine adjustments to brightness, contrast, clipping, and other characteristics. The image

10925-425: The soldiers, and their families,  thousands of which artefacts survive intact today. As The Times of London reported on August 30, 1862: America swarms with the members of the mighty tribe of cameristas, and the civil war has developed their business in the same way that it has given an impetus to the manufacturers of metallic air-tight coffins and embalmers of the dead. The young Volunteer rushes off at once to

11040-413: The studio when he puts on his uniform, and the soldier of a year's campaign sends home his likeness that the absent ones may see what changes have been produced in him by war's alarms. In every glade and by the roadsides of the camp may be seen all kinds of covered carts and portable sheds for the worker in metal acid and sun-ray. Washington has burst out into signboards of ambrotypists and collodionists, and

11155-434: The subject. Andrew Wynter noted in 1862 that: "The commercial value of the human face was never tested to such an extent as it is at the present moment in these handy photographs. No man, or woman either, knows but some accident may elevate them to the position of hero of the hour and send up the value their countenances to a degree they never dreamed of." By the early 1870s, cartes de visite began to be supplanted by

11270-438: The sun. Woodward's 1857 solar enlarging camera was a large instrument operated out-of-doors that could produce life size prints from quarter plate and half plate negatives with an exposure of about forty-five minutes, improved in the 1860s and 1870s with a clockwork heliostat to rotate the mirror in synchronisation with the sun's passage to concentrate its light on the condenser lens, while Désiré van Monckhoven 's 1863 patent

11385-410: The table or enlarger base, and held down flat with metal strips. The enlargement is made by first focusing the image with the lamp on, the lens at maximum aperture and the easel empty, usually with the aid of a focus finder . The lamp is turned off, or in some cases, shuttered by a light-tight mechanism. The image is focused by changing the distance between the lens and the film, achieved by adjusting

11500-471: The tens of kilowatts. Therefore, they were only practical for lighting large areas, so researchers continued to search for a way to make lamps suitable for home use. Over the first three-quarters of the 19th century, many experimenters worked with various combinations of platinum or iridium wires, carbon rods, and evacuated or semi-evacuated enclosures. Many of these devices were demonstrated and some were patented. In 1835, James Bowman Lindsay demonstrated

11615-560: The time, machinery to mass-produce coiled coil filaments did not exist. Hakunetsusha developed a method to mass-produce coiled coil filaments by 1936. Between 1924 and the outbreak of the Second World War, the Phoebus cartel attempted to fix prices and sales quotas for bulb manufacturers outside of North America. In 1925, Marvin Pipkin , an American chemist, patented a process for frosting

11730-690: Was Illuminated from behind with 61,000 watts of incandescent light; it was the first time a 35 mm picture had been used for an ongoing series of Kodak advertising displays there c.1950–1990. The transparency print was destroyed after exhibition. As the photographic market shifts away from film-based towards electronic imaging technology, many manufacturers no longer make enlargers for the professional photographer. Durst , which made high quality enlargers, stopped producing them in 2005, but still supports already sold models. Manufacturers old and new include: Incandescent light bulb An incandescent light bulb , incandescent lamp or incandescent light globe

11845-419: Was a British physicist and chemist. In 1850, he began working with carbonized paper filaments in an evacuated glass bulb. By 1860, he was able to demonstrate a working device but the lack of a good vacuum and an adequate supply of electricity resulted in a short lifetime for the bulb and an inefficient source of light. By the mid-1870s better pumps had become available, and Swan returned to his experiments. With

11960-492: Was a format of small photograph which was patented in Paris by photographer André Adolphe Eugène Disdéri in 1854, although first used by Louis Dodero . Each photograph was the size of a visiting card, and such photograph cards, in an early form of social media , were commonly traded among friends and visitors in the 1860s. Albums for the collection and display of cards became a common fixture in Victorian parlors. The popularity of

12075-456: Was a small component in his system of electric lighting, and no more critical to its effective functioning than the Edison Jumbo generator , the Edison main and feeder, and the parallel-distribution system. Other inventors with generators and incandescent lamps, and with comparable ingenuity and excellence, have long been forgotten because their creators did not preside over their introduction in

12190-582: Was a successful early Indian photographers who made carte-de visite portraits of literary, political, and business figures, the most famous of which was of the Maharaja of Baroda , thousands of which were circulated. While numbers of European photographers visited and practiced in the country, Lai Afong ( Chinese : 黎芳 ) was a successful Chinese-born photographer who, after working at the studio of Portuguese photographer José Joaquim Alves de Silvieria between 1865 and 1867, established Afong Studio in Hong Kong in

12305-472: Was even more affordable than the daguerreotype. Special cameras were designed with multiple lenses for their efficient production. Disdéri's 1854 patent was a camera of taking eight separate negatives on a single plate in a special holder. Rather than one large collodion plate being used to produce one image of the posed subject, Disdéri's design initially exposed ten images on one plate, exposed either simultaneously or in sequence. Each individual carte print

12420-446: Was for a modification of Woodward's design that had an appearance more like a modern horizontal enlarger. The instrument was used by significant photographers Disderi and Nadar. By 1890, artificial light sources – gas, petroleum, limelight, magnesium, and electric light bulb – were commonly used in enlargers, but even at the turn of the century simple folding daylight enlargers still found a use among amateurs to easily produce prints of

12535-493: Was granted the first patent for an incandescent lamp, with a design using platinum wires contained within a vacuum bulb. He also used carbon. In 1845, American John W. Starr patented an incandescent light bulb using carbon filaments. His invention was never produced commercially. In 1851, Jean Eugène Robert-Houdin publicly demonstrated incandescent light bulbs on his estate in Blois, France. His light bulbs are on display in

12650-500: Was lit by Joseph Swan's incandescent lamp on 3 February 1879. Thomas Edison began serious research into developing a practical incandescent lamp in 1878. Edison filed his first patent application for "Improvement in Electric Lights" on 14 October 1878. After many experiments, first with carbon in the early 1880s and then with platinum and other metals, in the end Edison returned to a carbon filament. The first successful test

12765-509: Was made at a fraction of the cost of producing one full-plate picture and ten were printed at once, saving time and thus efficiently serving the burgeoning consumer market for photography. Disdéri's patent was modified when making four images was found to be more practical, and in March 1860 optician Hyacinthe Hermagis patented a four-lens camera with a sliding back that became the standard. Désiré Monckhoven reported in 1859; We saw at M. Hermagis'

12880-448: Was on 22 October 1879, and lasted 13.5 hours. Edison continued to improve this design and by 4 November 1879, filed for a US patent for an electric lamp using "a carbon filament or strip coiled and connected ... to platina contact wires." Although the patent described several ways of creating the carbon filament including using "cotton and linen thread, wood splints, papers coiled in various ways," Edison and his team later discovered that

12995-549: Was the first in the world to be lit by a lightbulb. In the early 1880s he had started his company. In 1881, the Savoy Theatre in the City of Westminster , London was lit by Swan incandescent lightbulbs, which was the first theatre, and the first public building in the world, to be lit entirely by electricity. The first street in the world to be lit by an incandescent lightbulb was Mosley Street, Newcastle upon Tyne , United Kingdom . It

13110-492: Was tungsten. Lodygin invented a process where rare metals such as tungsten can be chemically treated and heat-vaporized onto an electrically heated thread-like wire (platinum, carbon, gold) acting as a temporary base or skeletal form. (US patent 575,002). Lodygin later sold the patent rights to GE. In 1902, Siemens developed a tantalum lamp filament that was more efficient than even graphitized carbon filaments since they could operate at higher temperature. Since tantalum metal has

13225-656: Was usually an albumen print from a collodion negative on thin paper glued onto a thicker paper card. The size of a carte de visite is 54 mm (2.125 in) × 89 mm (3.5 in) (approximately the size of a business card ), mounted on a card sized 64 mm (2.5 in) × 100 mm (4 in). The reverse was generally printed with the logo of the photographer or the photography studio from which it came, as both protection of copyright and advertising, and sometimes carried instructions for effective posing. The daguerreotype for portrait photography had met with immediate and widespread popularity and quickly displaced

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