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Rodinal is the trade name of a black and white developing agent produced originally by the German company Agfa based on the chemical 4-aminophenol. [1] Rodinal is a popular high acutance black and white developer and is used at different dilutions for development in rotary machines, by agitation, as well as for stand development.
Rodinal was patented on 27 January 1891, making it the oldest film developer which is still available to purchase. Novel at the time of its invention was that it is delivered as a liquid concentrate and not as a powder.
During the division of Germany the original manufacturer Agfa was split, becoming the ORWO company in East Germany, where it was sold under the name ORWO R09.
After the insolvency of Agfa in 2004, production was taken over by the re-formed ADOX, which also purchased the trademark rights in the name in Europe (excluding France) and continues to sell the product under this name.
Film stock is an analog medium that is used for recording motion pictures or animation. It is recorded on by a movie camera, developed, edited, and projected onto a screen using a movie projector. It is a strip or sheet of transparent plastic film base coated on one side with a gelatin emulsion containing microscopically small light-sensitive silver halide crystals. The sizes and other characteristics of the crystals determine the sensitivity, contrast and resolution of the film. The emulsion will gradually darken if left exposed to light, but the process is too slow and incomplete to be of any practical use. Instead, a very short exposure to the image formed by a camera lens is used to produce only a very slight chemical change, proportional to the amount of light absorbed by each crystal. This creates an invisible latent image in the emulsion, which can be chemically developed into a visible photograph. In addition to visible light, all films are sensitive to X-rays and high-energy particles. Most are at least slightly sensitive to invisible ultraviolet (UV) light. Some special-purpose films are sensitive into the infrared (IR) region of the spectrum.
Agfa-Gevaert N.V. (Agfa) is a Belgian-German multinational corporation that develops, manufactures, and distributes analogue and digital imaging products, software, and systems. It has three divisions:
ORWO is a brand of black and white film products, made in Germany.
In photography, reversal film or slide film is a type of photographic film that produces a positive image on a transparent base. Instead of negatives and prints, reversal film is processed to produce transparencies or diapositives. Reversal film is produced in various sizes, from 35 mm to roll film to 8×10 inch sheet film.
C-41 is a chromogenic color print film developing process introduced by Kodak in 1972, superseding the C-22 process. C-41, also known as CN-16 by Fuji, CNK-4 by Konica, and AP-70 by AGFA, is the most popular film process in use, with most photofinishing labs devoting at least one machine to this development process.
Technical Pan is an almost panchromatic black-and-white film that was produced by Kodak. While it can reproduce the visible light spectrum, it leans to the red, and so unfiltered outdoor shots render blues, most notably the sky, with additional darkening and reds with some lightening. It was generally used as a very slow film, rated at EI 25 or even 16, although it could be rated at up to EI 320 with a distinct loss of tonal range and a bunching of shadow and highlight detail. This film has unmatched fine grain, especially when rated at a low speed, and makes excellent enlargements while preserving fine details. Kodak stopped selling it in 2004. It has not been replaced by a film with its characteristics. Although some of its particularities were unique and no emulsion in actual production could replace it, its resolution capabilities were surpassed by another film by ADOX, CMS 20 II.
Agfacolor was the name of a series of color film products made by Agfa of Germany. The first Agfacolor, introduced in 1932, was a film-based version of their Agfa-Farbenplatte, a "screen plate" product similar to the French Autochrome. In late 1936, Agfa introduced Agfacolor Neu, a pioneering color film of the general type still in use today. The new Agfacolor was originally a reversal film used for making "slides", home movies and short documentaries. By 1939, it had also been adapted into a negative film and a print film for use by the German motion picture industry. After World War II, the Agfacolor brand was applied to several varieties of color negative film for still photography, in which the negatives were used to make color prints on paper. The reversal film was then marketed as Agfachrome. These films use Color Developing Agent 1 in their color developer.
The Sabatier effect, also known as pseudo-solarization and erroneously referred to as the Sabattier effect, is a phenomenon in photography in which the image recorded on a negative or on a photographic print is wholly or partially reversed in tone. Dark areas appear light or light areas appear dark. Solarization and pseudo-solarization are quite distinct effects. Over time, the "pseudo" has been dropped in many photographic darkroom circles and discussions, but the effect that is meant is the Sabattier effect and not the solarization by extreme overexposure.
The ADOX brand for photographic purposes has been used by three different companies since its original conception over one hundred fifty years ago. ADOX was originally a brand name used by the German company, Fotowerke Dr. C. Schleussner GmbH of Frankfurt am Main, the world's first photographic materials manufacturer. In 1962 the Schleussner family sold its photographic holdings to DuPont, an American company. DuPont used the brand for its subsidiary, Sterling Diagnostic Imaging for X-ray films. In 1999, Sterling was bought by the German company Agfa. Agfa did not use the brand and allowed its registration to lapse in 2003. Fotoimpex of Berlin, Germany, a company founded in 1992 to import photographic films and papers from former eastern Europe immediately registered the brand and today ADOX is a brand of black and white films, photographic papers and photochemistry produced by ADOX Fotowerke GmbH based in Bad Saarow near Berlin.
Wolfen is a town in the district Anhalt-Bitterfeld, Saxony-Anhalt, Germany. Since 1 July 2007 it is part of the town Bitterfeld-Wolfen. It is situated approximately 6 kilometres northwest of Bitterfeld, and 20 kilometres south of Dessau.
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.
A chromogenic print, also known as a C-print or C-type print, a silver halide print, or a dye coupler print, is a photographic print made from a color negative, transparency or digital image, and developed using a chromogenic process. They are composed of three layers of gelatin, each containing an emulsion of silver halide, which is used as a light-sensitive material, and a different dye coupler of subtractive color which together, when developed, form a full-color image.
RA-4 is Kodak's proprietary name for the chemical process most commonly used to make color photographic prints. It is used for both minilab wet silver halide digital printers of the types most common today in photo labs and drug stores, and for prints made with older-type optical enlargers and manual processing.
Momme Andresen was a Danish-German industrial research chemist. His main area of work was to formulate better developers and fixers for black-and-white photographs.
The South Indian film industry produced colour films since the 40s, especially the Kollywood. The earliest colour films in India were also produced in South India.
Agfacontour Professional was a special emulsion sheet film which, after exposure and development in the Agfacontour developer, produced direct equidensities.
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