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Mordançage
Mordançage is an alternative photographic process that alters silver gelatin prints to give them a degraded effect. The mordançage solution works in two ways: it chemically bleaches the print so that it can be redeveloped, and it lifts the black areas of the emulsion away from the paper, giving the appearance of veils. Once the emulsion is lifted, it can then be removed or manipulated depending on the desired outcome. Areas where the emulsion was removed appear to be in relief. These prints can become oxidized during their creation, further altering the tonality of the image. History Mordançage was created by Jean-Pierre Sudre during the 1960s. While he is credited with the creation of Mordançage, it is based on a late 19th-century process known as etch-bleach. This process has also been referred to as bleach-etch, gelatin relief, or reverse relief. Etch-bleach was first documented in 1897 by Paul Liesegang and was originally used as a reversal process for film negatives. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Jean-Pierre Sudre
Jean-Pierre Sudre (; September 27, 1921 – September 6, 1997) was a commercial photographer. Biography Sudre was born in Paris but later moved to the south of France. There he devoted his life to workshops of fine art photography. Photography Sudre's subject-matter was mainly the still-life and figure. He is best known for his experimentation with chemicals, and is credited with the creation of Mordançage (tr. 'etching', ' scouring'), though he built the process on the film reversal technique first documented in 1897 by Paul Liesegang and known as etch-bleach, bleach-etch, gelatin relief, or reverse relief. Recognition On its foundation in 1952, Sudre was invited to become the honorary president of Les 30 x 40, Club Photographique de Paris in 1957 Sudre was awarded the Lion d'Or at the first Biennale Internationale de la Photographie at Venice, Italy. In 1970, at the invitation of writer Michel Tournier, Sudre participated in the first Rencontres d'Arles as a guest of honou ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Self Portrait (8618889472)
Self-portraits are Portrait painting, portraits artists make of themselves. Although self-portraits have been made since the earliest times, the practice of self-portraiture only gaining momentum in the Early Renaissance in the mid-15th century that artists can be frequently identified depicting themselves as either the main subject, or as important characters in their work. With better and cheaper mirrors, and the advent of the panel painting, panel portrait, many painters, sculptors and printmakers tried some form of self-portraiture. ''Portrait of a Man in a Turban'' by Jan van Eyck of 1433 may well be the earliest known panel self-portrait. He painted a separate portrait of his wife, and he belonged to the social group that had begun to commission portraits, already more common among wealthy Netherlanders than south of the Alps. The genre is venerable, but not until the Renaissance, with increased wealth and interest in the individual as a subject, did it become truly popular. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hydrogen Peroxide
Hydrogen peroxide is a chemical compound with the formula . In its pure form, it is a very pale blue liquid that is slightly more viscosity, viscous than Properties of water, water. It is used as an oxidizer, bleaching agent, and antiseptic, usually as a dilute solution (3%–6% by weight) in water for consumer use and in higher concentrations for industrial use. Concentrated hydrogen peroxide, or "high-test peroxide", decomposes explosively when heated and has been used as both a monopropellant and an oxidizer in rocketry. Hydrogen peroxide is a reactive oxygen species and the simplest peroxide, a compound having an oxygen–oxygen single bond. It decomposes slowly into water and elemental oxygen when exposed to light, and rapidly in the presence of organic or reactive compounds. It is typically stored with a Stabilizer (chemistry), stabilizer in a weakly acidic solution in an opaque bottle. Hydrogen peroxide is found in biological systems including the human body. Enzymes that u ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stop Bath
A stop bath is an acidic solution used for processing black-and-white photographic film, plates, and paper. It is used to neutralize the alkaline developer, thus halting development. A stop bath is commonly a 2% dilution of acetic acid in water, though a 2.5% solution of potassium Potassium is a chemical element; it has Symbol (chemistry), symbol K (from Neo-Latin ) and atomic number19. It is a silvery white metal that is soft enough to easily cut with a knife. Potassium metal reacts rapidly with atmospheric oxygen to ... or sodium metabisulfite works just as well. Because organic developers only work in alkaline solutions, stop baths halt the development process almost immediately and provides precise control of development time. Neutralizing the alkalinity of basic developers also helps to preserve the strength of the fixer, making it last longer. Stop baths account for the vinegar-like odor of the darkroom. In its concentrated form it can cause chemical burns, but ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Photographic Fixer
Photographic fixer is a mixture of chemicals used in the final step in the photographic processing of film or paper. The fixer stabilises the image, removing the unexposed silver halide remaining on the photographic film or photographic paper, leaving behind the reduced metallic silver that forms the image. By fixation, the film or paper is insensitive to further action by light. Without fixing, the remaining silver halide would darken and cause fogging of the image. Chemistry Fixation is commonly achieved by treating the film or paper with a solution of thiosulfate salt. Popular salts are sodium thiosulfate—commonly called hypo—and ammonium thiosulfate—commonly used in modern rapid fixer formulae. Fixation by thiosulfate involves these chemical reactions (X = halide, typically Br−):Karlheinz Keller et al. "Photography" in Ullmann's Encyclopedia of Industrial Chemistry, 2005, Wiley-VCH, Weinheim. . :AgX + 2 S2O32− → g(S2O3)2sup>3− + X− :AgX + 3 S2O32− → ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Photographic Developer
In the Photographic processing, processing of photographic films, plates or papers, the photographic developer (or just developer) is one or more chemicals that convert the latent image to a visible image. Developing agents achieve this conversion by Redox, reducing the silver halides, which are pale-colored, into silver metal, which is black when in the form of fine particles.Karlheinz Keller et al. ''Photography'' in ''Ullmann's Encyclopedia of Industrial Chemistry'', 2005, Wiley-VCH, Weinheim. . The conversion occurs within the gelatine matrix. The special feature of photography is that the developer acts more quickly on those particles of silver halide that have been exposed to light. When left in developer, all the silver halides will eventually be reduced and turn black. Generally, the longer a developer is allowed to work, the darker the image. Chemical composition of developers The developer typically consists of a mixture of chemical compounds prepared as an aqueous solut ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Photographic Paper
Photographic paper is a coated paper, paper coated with a light-sensitive chemical, used for making photographic prints. When photographic paper is exposed to light, it captures a latent image that is then Photographic developer, developed to form a visible image; with most papers the image density from exposure can be sufficient to not require further development, aside from fixing and clearing, though latent exposure is also usually present. The light-sensitive layer of the paper is called the emulsion, and functions similarly to photographic film. The most common chemistry used is Gelatin silver print, gelatin silver, but other alternatives have also been used. The print image is traditionally produced by interposing a Negative (photography), photographic negative between the light source and the paper, either by direct contact with a large negative (forming a contact print) or by projecting the shadow of the negative onto the paper (producing an enlargement). The initial light ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Distilled Water
Distilled water is water that has been purified by boiling it into vapor then condensing it back into liquid in a separate container. Impurities in the original water that do not boil below or near the boiling point of water remain in the original container. History Drinking water has been distilled from seawater since at least about AD 200, when the process was clearly described by Alexander of Aphrodisias. Its history predates this, as a passage in Aristotle's '' Meteorologica'' refers to the distillation of water. Captain Israel Williams of the ''Friendship'' (1797) improvised a way to distill water, which he described in his journal. Applications In chemical and biological laboratories, as well as in industry, in some appliances, deionized water or reverse osmosis water can be used instead of distilled water as a cheaper alternative. If exceptionally high-purity water is required, double distilled water is used. In general, non-purified water could cause or interfere ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Glacial Acetic Acid
Acetic acid , systematically named ethanoic acid , is an acidic, colourless liquid and organic compound with the chemical formula (also written as , , or ). Vinegar is at least 4% acetic acid by volume, making acetic acid the main component of vinegar apart from water. Historically, vinegar was produced from the third century BC and was likely the first acid to be produced in large quantities. Acetic acid is the second simplest carboxylic acid (after formic acid). It is an important chemical reagent and industrial chemical across various fields, used primarily in the production of cellulose acetate for photographic film, polyvinyl acetate for wood glue, and synthetic fibres and fabrics. In households, diluted acetic acid is often used in descaling agents. In the food industry, acetic acid is controlled by the food additive code E260 as an acidity regulator and as a condiment. In biochemistry, the acetyl group, derived from acetic acid, is fundamental to all forms of life. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gelatin Silver Print
The gelatin silver print is the most commonly used chemical process in black-and-white photography, and is the fundamental chemical process for modern analog color photography. As such, films and printing papers available for analog photography rarely rely on any other chemical process to record an image. A suspension of silver salts in gelatin is coated onto a support such as glass, flexible plastic or film, baryta paper, or resin-coated paper. These light-sensitive materials are stable under normal keeping conditions and are able to be exposed and processed even many years after their manufacture. The "dry plate" gelatin process was an improvement on the collodion wet-plate process dominant from the 1850s–1880s, which had to be exposed and developed immediately after coating. History Gelatine was used to copy the images of Daguerreotypes by 1845 and Alphonse Louis Poitevin wrote about positive proofs of negatives on dry gelatine plates in 1850. In the 1860s, the dry ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Copper(II) Chloride
Copper(II) chloride, also known as cupric chloride, is an inorganic compound with the chemical formula . The monoclinic crystal system, monoclinic yellowish-brown anhydrous form slowly absorbs moisture to form the orthorhombic blue-green hydrate, dihydrate , with two water of crystallization, water molecules of hydration. It is industrially produced for use as a catalyst, co-catalyst in the Wacker process. Both the anhydrous and the dihydrate forms occur naturally as the rare minerals tolbachite and eriochalcite, respectively. Structure Anhydrous copper(II) chloride adopts a distorted cadmium iodide structure. In this structure, the copper centers are octahedral molecular geometry, octahedral. Most copper(II) compounds exhibit distortions from idealized Octahedral molecular geometry, octahedral geometry due to the Jahn-Teller effect, which in this case describes the localization of one electron, d-electron into a molecular orbital that is strongly antibonding molecular orbital, an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
