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Ilfochrome
Ilfochrome (also commonly known as Cibachrome) is a dye destruction positive-to-positive photographic process used for the reproduction of film transparencies on photographic paper. The prints are made on a dimensionally stable polyester base as opposed to traditional paper base. Since it uses 13 layers of azo dyes sealed in a polyester base, the print will not fade, discolour, or deteriorate for an extended time. Accelerated aging tests conducted by Henry Wilhelm rated the process as producing prints which, framed under glass, would last for 29 years before color shifts could be detected. Characteristics of Ilfochrome prints are image clarity, color purity, and being an archival process able to produce critical accuracy to the original transparency. History Dr. Bela Gaspar created Gasparcolor, the dye bleach process upon which the Cibachrome process was originally based. It was considered vital to the war effort in the 1940s. Gaspar turned down many offers to sell the rights ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Photographic Paper
Photographic paper is a paper coated with a light-sensitive chemical formula, like photographic film, used for making photographic prints. When photographic paper is exposed to light, it captures a latent image that is then 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. The most common chemistry was based on silver halide (the focus of this page) but other alternatives have also been used. The print image is traditionally produced by interposing a 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 exposure is carefully controlled to produce a gray scale image on th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dye Destruction
Dye destruction or dye bleach is a photographic printing process, in which dyes embedded in the paper are bleached (destroyed) in processing. Because the dyes are fully formed in the paper prior to processing, they may be formulated with few constraints, compared to the complex dye couplers that must react in chromogenic processing. This method has allowed the use of richly colored, highly stable dyes. It is a reversal process, meaning that it is used in printing transparencies (diapositives). Ilfochrome (originally Cibachrome) is currently the only widely available dye destruction process, and is known for its intense colors and archival qualities. Older dye destruction processes included Utocolor (early 1900s) and Gasparcolor Gasparcolor was a color motion picture film system, developed in Berlin in 1933 by the Hungarian chemist Dr. Béla Gáspár ( Oraviczbánya, Transylvania 1898-1973). It used a subtractive 3-color process on a single film strip, one of the earli ... (1930s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ilford Photo
Harman Technology, trading as Ilford Photo, is a UK-based manufacturer of photographic materials known worldwide for its ILFORD branded black-and-white film, papers and chemicals. Historically it also published the '' Ilford Manual of Photography'', a comprehensive manual of everything photographic, including the optics, physics and chemistry of photography, along with recipes for many developers. Under the ownership of the industrial conglomerate ICI in the 1960s, the company produced a range of Ilfochrome (Cibachrome) and Ilfocolor colour printing materials at a new plant in Switzerland developed in partnership with the Swiss company CIBA-Geigy, which later acquired ICIs shares. By the 2000s, as the UK - Swiss company Ilford Imaging, the decline of the film market saw the UK company in receivership by 2004, but rescued by a management buy out; Harman Technology Ltd, which today continues the production of traditional black-and-white photographic materials, under the ILFORD, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Focal Press
Focal Press is a publisher of creative and applied media books and it is an imprint of Routledge/Taylor & Francis. Company history The firm was founded in London in 1938 by Andor Kraszna-Krausz, a Hungarian photographer who migrated to England in 1937 and eventually published over 1,200 books on photography, cinematography and broadcasting. It "published practical guides to photography at affordable prices for the general public". One of the books published by Kraszna-Krausz's Focal Press was ''The All-in-One Camera Book'' by E. Emanuel and W. D. Dash, which was one of the earliest books on photography written for the general public. First published in 1939 it had gone through 81 editions by 1978. Book series published by the firm included Masters of the Camera and Classics of Photography. There was a second firm named Focal Press which was founded by George Bernhard Eisler in London in 1937 and later opened a branch in New York. It is unclear if there was a connection betwe ... [...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 camera len ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Daguerreotype
Daguerreotype (; french: daguerréotype) was the first publicly available photographic process; it was widely used during the 1840s and 1850s. "Daguerreotype" also refers to an image created through this process. Invented by Louis Daguerre and introduced worldwide in 1839, the daguerreotype was almost completely superseded by 1860 with new, less expensive processes, such as ambrotype ( collodion process), that yield more readily viewable images. There has been a revival of the daguerreotype since the late 20th century by a small number of photographers interested in making artistic use of early photographic processes. To make the image, a daguerreotypist polished a sheet of silver-plated copper to a mirror finish; treated it with fumes that made its surface light-sensitive; exposed it in a camera for as long as was judged to be necessary, which could be as little as a few seconds for brightly sunlit subjects or much longer with less intense lighting; made the resulting lat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Photographic Plate
Photographic plates preceded photographic film as a capture medium in photography, and were still used in some communities up until the late 20th century. The light-sensitive emulsion of silver salts was coated on a glass plate, typically thinner than common window glass. History Glass plates were far superior to film for research-quality imaging because they were stable and less likely to bend or distort, especially in large-format frames for wide-field imaging. Early plates used the wet collodion process. The wet plate process was replaced late in the 19th century by gelatin dry plates. A view camera nicknamed "The Mammoth" weighing was built by George R. Lawrence in 1899, specifically to photograph "The Alton Limited" train owned by the Chicago & Alton Railway. It took photographs on glass plates measuring × . Glass plate photographic material largely faded from the consumer market in the early years of the 20th century, as more convenient and less fragile fil ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Large Format
Large format refers to any imaging format of or larger. Large format is larger than "medium format", the or size of Hasselblad, Mamiya, Rollei, Kowa, and Pentax cameras (using 120- and 220-roll film), and much larger than the frame of 35 mm format. The main advantage of a large format, film or digital, is a higher resolution at the same pixel pitch, or the same resolution with larger pixels or grains which allows each pixel to capture more light enabling exceptional low-light capture. A 4×5 inch image (12.903 mm²) has about 15 times the area, and thus 15× the total resolution, of a 35 mm frame (864 mm²). Large format cameras were some of the earliest photographic devices, and before enlargers were common, it was normal to just make 1:1 contact prints from a 4×5, 5×7, or 8×10-inch negative. Formats The most common large format is 4×5 inches (10.2x12.7 cm), which was the size used by cameras like the Graflex Speed Graphic and Crown Gr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chromogenic
In chemistry, the term chromogen refers to a colourless (or faintly coloured) chemical compound that can be converted by chemical reaction into a compound which can be described as "coloured". There is no universally agreed definition of the term. Various dictionaries give the following definitions: * A substance capable of conversion into a pigment or dye. * Any substance that can become a pigment or coloring matter, a substance in organic fluids that forms colored compounds when oxidized, or a compound, not itself a dye, that can become a dye. * Any substance, itself without color, giving origin to a coloring matter. In biochemistry the term has a rather different meaning. The following are found in various dictionaries. * A precursor of a biochemical pigment * A pigment-producing microorganism * Any of certain bacteria that produce a pigment * A strongly pigmented or pigment-generating organelle, organ, or microorganism. Applications in chemistry *In chromogenic photography, f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Azo Dye
Azo dyes are organic compounds bearing the functional group R−N=N−R′, in which R and R′ are usually aryl and substituted aryl groups. They are a commercially important family of azo compounds, i.e. compounds containing the C-N=N-C linkage. Azo dyes are synthetic dyes and do not occur naturally. Most azo dyes contain only one azo group, but some dyes called "disazo dyes" contain two azo groups, some dyes called "trisazo dyes" contain three azo groups and are or more. Azo dyes comprise 60-70% of all dyes used in food and textile industries. Azo dyes are widely used to treat textiles, leather articles, and some foods. Chemically related derivatives of azo dyes include azo pigments, which are insoluble in water and other solvents. Classes Many kinds of azo dyes are known, and several classification systems exist. Some classes include disperse dyes, metal-complex dyes, reactive dyes, and substantive dyes. Also called direct dyes, substantive dyes are employed for ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Emulsion
An emulsion is a mixture of two or more liquids that are normally immiscible (unmixable or unblendable) owing to liquid-liquid phase separation. Emulsions are part of a more general class of two-phase systems of matter called colloids. Although the terms ''colloid'' and ''emulsion'' are sometimes used interchangeably, ''emulsion'' should be used when both phases, dispersed and continuous, are liquids. In an emulsion, one liquid (the dispersed phase) is dispersed in the other (the continuous phase). Examples of emulsions include vinaigrettes, homogenized milk, liquid biomolecular condensates, and some cutting fluids for metal working. Two liquids can form different types of emulsions. As an example, oil and water can form, first, an oil-in-water emulsion, in which the oil is the dispersed phase, and water is the continuous phase. Second, they can form a water-in-oil emulsion, in which water is the dispersed phase and oil is the continuous phase. Multiple emulsions are also pos ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
