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Photographic Studio
A photographic studio is often a business owned and represented by one or more photographers, possibly accompanied by assistants and pupils, who create and sell their own and sometimes others’ photographs. Since the early years of the 20th century the business functions of a photographic studio have increasingly been called a photographic agency leaving the term "photographic studio" to refer almost exclusively to the workspace. The history of photographic studios and photography dates back to the 1840s with the invention of processes for recording camera pictures, by Henry Fox Talbot and Louis Daguerre. The earliest photographic studios made use of natural daylight to create photographic portraits. As already used by artists, a northern light with no direct sunlight was favoured. The first use of a "flash" dates back to 1839 when L. Ibbetson used limelight to photograph very small objects. Limelight was produced by placing a piece of lime into a flame fuelled with oxy-h ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Photo Studio - 22 Feb
A photograph (also known as a photo, image, or picture) is an image created by light falling on a photosensitive surface, usually photographic film or an electronic image sensor, such as a CCD or a CMOS chip. Most photographs are now created using a smartphone/camera, which uses a lens to focus the scene's visible wavelengths of light into a reproduction of what the human eye would see. The process and practice of creating such images is called photography. Etymology The word ''photograph'' was coined in 1839 by Sir John Herschel and is based on the Greek φῶς (''phos''), meaning "light," and γραφή (''graphê''), meaning "drawing, writing," together meaning "drawing with light." History The first permanent photograph, a contact-exposed copy of an engraving, was made in 1822 using the bitumen-based "heliography" process developed by Nicéphore Niépce. The first photographs of a real-world scene, made using a camera obscura, followed a few years later at Le Gras, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Magnesium
Magnesium is a chemical element with the symbol Mg and atomic number 12. It is a shiny gray metal having a low density, low melting point and high chemical reactivity. Like the other alkaline earth metals (group 2 of the periodic table) it occurs naturally only in combination with other elements and it almost always has an oxidation state of +2. It reacts readily with air to form a thin passivation coating of magnesium oxide that inhibits further corrosion of the metal. The free metal burns with a brilliant-white light. The metal is obtained mainly by electrolysis of magnesium salts obtained from brine. It is less dense than aluminium and is used primarily as a component in strong and lightweight alloys that contain aluminium. In the cosmos, magnesium is produced in large, aging stars by the sequential addition of three helium nuclei to a carbon nucleus. When such stars explode as supernovas, much of the magnesium is expelled into the interstellar medium where it m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ambrotype
The ambrotype (from grc, ἀμβροτός — “immortal”, and — “impression”) also known as a collodion positive in the UK, is a positive photograph on glass made by a variant of the wet plate collodion process. Like a print on paper, it is viewed by reflected light. Like the daguerreotype, which it replaced, and like the prints produced by a Polaroid camera, each is a unique original that could only be duplicated by using a camera to copy it. The ambrotype was introduced in the 1850s. During the 1860s it was superseded by the tintype, a similar photograph on thin black-lacquered iron, hard to distinguish from an ambrotype if under glass. Process One side of a clean glass plate was coated with a thin layer of iodized collodion, then dipped in a silver nitrate solution. The plate was exposed in the camera while still wet. Exposure times varied from five to sixty seconds or more depending on the brightness of the lighting and the speed of the came ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Calotype
Calotype or talbotype is an early photographic process introduced in 1841 by William Henry Fox Talbot, using paper coated with silver iodide. Paper texture effects in calotype photography limit the ability of this early process to record low contrast details and textures. The term ''calotype'' comes from the Ancient Greek (), "beautiful", and (), "impression". The process Talbot made his first successful camera photographs in 1835 using paper sensitised with silver chloride, which darkened in proportion to its exposure to light. This early "photogenic drawing" process was a ''printing-out'' process, i.e., the paper had to be exposed in the camera until the image was fully visible. A very long exposure—typically an hour or more—was required to produce an acceptable negative. In late 1840, Talbot worked out a very different ''developing-out'' process (a concept pioneered by the daguerreotype process introduced in 1839), in which only an extremely faint or completely ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Portrait
A portrait is a painting, photograph, sculpture, or other artistic representation of a person, in which the face and its expressions are predominant. The intent is to display the likeness, personality, and even the mood of the person. For this reason, in photography a portrait is generally not a snapshot, but a composed image of a person in a still position. A portrait often shows a person looking directly at the painter or photographer, in order to most successfully engage the subject with the viewer. History Prehistorical portraiture Plastered human skulls were reconstructed human skulls that were made in the ancient Levant between 9000 and 6000 BC in the Pre-Pottery Neolithic B period. They represent some of the oldest forms of art in the Middle East and demonstrate that the prehistoric population took great care in burying their ancestors below their homes. The skulls denote some of the earliest sculptural examples of portraiture in the history of art. Historical portrait ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Flash Powder
Flash powder is a pyrotechnic composition, a mixture of oxidizer and metallic fuel, which burns quickly and produces a loud noise regardless of confinement. It is widely used in theatrical pyrotechnics and fireworks (namely salutes, e.g., cherry bombs, M-80s, firecrackers, and cap gun shots) and was once used for flashes in photography. Different varieties of flash powder are made from different compositions; most common are potassium perchlorate and aluminium powder. Sometimes, sulfur is included in the mixture to increase the sensitivity. Early formulations used potassium chlorate instead of potassium perchlorate. Flash powder compositions are also used in military pyrotechnics when production of large amount of noise, light, or infrared radiation is required, e.g., missile decoy flares and stun grenades. History Lycopodium powder is a yellow-tan dust-like powder historically used as a flash powder. Today, the principal use of the powder is to create flashes or flames t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Strobe Light
A strobe light or stroboscopic lamp, commonly called a strobe, is a device used to produce regular flashes of light. It is one of a number of devices that can be used as a stroboscope. The word originated from the Ancient Greek ('), meaning "act of whirling". A typical commercial strobe light has a flash energy in the region of 10 to 150 joules, and discharge times as short as a few milliseconds, often resulting in a flash power of several kilowatts. Larger strobe lights can be used in “continuous” mode, producing extremely intense illumination. The light source is commonly a xenon flash lamp, or ''flashtube'', which has a complex spectrum and a color temperature of approximately 5,600 kelvins. To obtain colored light, colored gels may be used. Scientific explanation of flashtubes Strobe lights usually use flashtubes with energy supplied from a capacitor, an energy storage device much like a battery, but capable of charging and releasing energy much faster. In a c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tungsten
Tungsten, or wolfram, is a chemical element with the symbol W and atomic number 74. Tungsten is a rare metal found naturally on Earth almost exclusively as compounds with other elements. It was identified as a new element in 1781 and first isolated as a metal in 1783. Its important ores include scheelite and wolframite, the latter lending the element its alternate name. The free element is remarkable for its robustness, especially the fact that it has the highest melting point of all known elements barring carbon (which sublimes at normal pressure), melting at . It also has the highest boiling point, at . Its density is , comparable with that of uranium and gold, and much higher (about 1.7 times) than that of lead. Polycrystalline tungsten is an intrinsically brittle and hard material (under standard conditions, when uncombined), making it difficult to work. However, pure single-crystalline tungsten is more ductile and can be cut with a hard-steel hacksaw. Tungsten occ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oxyhydrogen
Oxyhydrogen is a mixture of hydrogen (H2) and oxygen (O2) gases. This gaseous mixture is used for torches to process refractory materials and was the first gaseous mixture used for welding. Theoretically, a ratio of 2:1 hydrogen:oxygen is enough to achieve maximum efficiency; in practice a ratio 4:1 or 5:1 is needed to avoid an oxidizing flame. This mixture may also be referred to as ' (Scandinavian and German Knallgas: "bang-gas"), although some authors define knallgas to be a generic term for the mixture of fuel with the precise amount of oxygen required for complete combustion, thus 2:1 oxyhydrogen would be called "hydrogen-knallgas". "Brown's gas" and HHO are terms for oxyhydrogen mainly encountered in fringe science. Properties Oxyhydrogen will combust when brought to its autoignition temperature. For the stoichiometric mixture, 2:1 hydrogen:oxygen, at normal atmospheric pressure, autoignition occurs at about 570 °C (1065 °F). The minimum energy required ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Limelight
Limelight (also known as Drummond light or calcium light)James R. Smith (2004). ''San Francisco's Lost Landmarks'', Quill Driver Books. is a type of stage lighting once used in theatres and music halls. An intense illumination is created when a flame fed by oxygen and hydrogen is directed at a cylinder of quicklime (calcium oxide), which can be heated to before melting. The light is produced by a combination of incandescence and candoluminescence. Although it has long since been replaced by electric lighting, the term has nonetheless survived, as someone in the public eye is still said to be "in the limelight". The actual lamps are called "limes", a term which has been transferred to electrical equivalents. History Discovery and invention The limelight effect was discovered in the 1820s by Goldsworthy Gurney, based on his work with the "oxy-hydrogen blowpipe", credit for which is normally given to Robert Hare. In 1825, a Scottish engineer, Thomas Drummond (1797–1840 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Levett Landon Boscawen Ibbetson
Captain Levett Landon Boscawen Ibbetson (1799 – 8 September 1869) was an English 19th century geologist, inventor, organiser and soldier. He is particularly associated with early developments in photography. He was a member of the London Electrical Society and later a Fellow of the Royal Society (elected 6 June 1850). Life From his London home (46 Margaret Street, near Cavendish Square), Ibbetson corresponded with William Henry Fox Talbot in 1842, having spent some years trying to produce a lithograph from an original daguerrotype, writing "I have been going on with experiments in the Callotype & have had some very good results as to depth of Colour." Ten years later, in 1852, Ibbetson exhibited work produced using the Talbot calotype process, called ''Le Premier Livre Imprimè par le Soleil'', at a London Society of Arts exhibition. This book, originally published in 1840, was an album of contact prints of ferns, grasses and flowers and used "the independently invented ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
