Kallitype is a process for making photographic prints.
Patented in 1889 by W. W. J. Nicol (1855-1929), the Kallitype print is an iron-silver process. A chemical process similar to the Van Dyke brown based on the use of a combination of ferric and silver salts. While Van Dyke brown and argyrotype use ferric ammonium citrate, the light-sensitive element used for the Kallitype is ferric oxalate. [1] The use of ferric oxalate allows for both extended shadow definition (higher DMAX) and contrast control. [1]
Many developing solutions can be used to give a different image color (brown, sepia, blue, maroon and black). Kallitype images generally have a richer tonal range than the cyanotype. These prints were popular in the 19th century, and then their popularity faded away. Sometimes known as "the poor man's platinum print", when the image is toned in platinum or palladium the result is nearly chemically identical to a true Platinotype. It is believed that many Kallitypes were passed off as true Platinotypes and remain in collections as so. Kallitypes have had a reputation over the years as having poor archival qualities and often fading. When properly cleared, Kallitypes are completely archivable and will not fade. Toning with a metal such as gold, platinum, or palladium will give extra image permanence. Ferrous ions embedded in the paper as a result of poor clearing is the cause of the lack of belief in image permanence. This can be easily identified by a yellow stain in the highlights.
Like the Platinotype and Cyanotype, the kallitype is a contact printing process and the printer must have a negative of equal size to print from. Modern kallitypes are generally made from either a large format camera negative, an enlarged internegative from a traditional wet darkroom, or a digital negative. Cotton rag paper is generally recommended for printing kallitypes, [2] although multiple paper types will lead to satisfactory results. [3] Gloves should be worn during coating and when handling sensitizer as the sensitizer chemicals can be quite toxic. While the Van Dyke Brown and Argyrotype are both "printing out" processes (with the complete image being formed during exposure), the Kallitype is a "develop out" process that requires the print to be submerged in a developer solution to make the image visible after exposure. [4] Like the Platinotype, the image will appear instantly when the paper is submerged in the developer.
The final tone of the print is controlled both via the developer choice [5] and through the use of toning solutions such as gold and platinum toners. [1]
A blueprint is a reproduction of a technical drawing or engineering drawing using a contact print process on light-sensitive sheets. Introduced by Sir John Herschel in 1842, the process allowed rapid and accurate production of an unlimited number of copies. It was widely used for over a century for the reproduction of specification drawings used in construction and industry. The blueprint process was characterized by white lines on a blue background, a negative of the original. The process was not able to reproduce color or shades of grey.
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 but other alternatives have also been used.
The cyanotype is a slow-reacting, economical photographic printing formulation sensitive to a limited near ultraviolet and blue light spectrum, the range 300 nm to 400 nm known as UVA radiation. It produces a cyan-blue print used for art as monochrome imagery applicable on a range of supports, and for reprography in the form of blueprints. For any purpose, the process usually uses two chemicals: ferric ammonium citrate or ferric ammonium oxalate, and potassium ferricyanide, and only water to develop and fix. Announced in 1842, it is still in use.
The gelatin silver process 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.
A contact print is a photographic image produced from film; sometimes from a film negative, and sometimes from a film positive or paper negative. In a darkroom an exposed and developed piece of film or photographic paper is placed emulsion side down, in contact with a piece of photographic paper, light is briefly shone through the negative or paper and then the paper is developed to reveal the final print.
Photographic printing is the process of producing a final image on paper for viewing, using chemically sensitized paper. The paper is exposed to a photographic negative, a positive transparency , or a digital image file projected using an enlarger or digital exposure unit such as a LightJet or Minilab printer. Alternatively, the negative or transparency may be placed atop the paper and directly exposed, creating a contact print. Digital photographs are commonly printed on plain paper, for example by a color printer, but this is not considered "photographic printing".
Platinum prints, also called platinotypes, are photographic prints made by a monochrome printing process involving platinum.
Sun printing may refer to various printing techniques which use sunlight as a developing or fixative agent.
The term alternative process refers to any non-traditional or non-commercial photographic printing process. Currently, the standard analog photographic printing process for black-and-white photographs is the gelatin silver process. Standard digital processes include the pigment print, and digital laser exposures on traditional color photographic paper.
In photography, toning is a method of altering the color of black-and-white photographs. In analog photography, it is a chemical process carried out on metal salt-based prints, such as silver prints, iron-based prints, or platinum or palladium prints. This darkroom process cannot be performed with a color photograph. The effects of this process can be emulated with software in digital photography. Sepia is considered a form of black-and-white or monochrome photography.
Gum bichromate is a 19th-century photographic printing process based on the light sensitivity of dichromates. It is capable of rendering painterly images from photographic negatives. Gum printing is traditionally a multi-layered printing process, but satisfactory results may be obtained from a single pass. Any color can be used for gum printing, so natural-color photographs are also possible by using this technique in layers.
Chrysotype is a photographic process invented by John Herschel in 1842. Named from the Greek for "gold", it uses colloidal gold to record images on paper.
The following outline is provided as an overview of and topical guide to photography:
Architectural reprography, the reprography of architectural drawings, covers a variety of technologies, media, and supports typically used to make multiple copies of original technical drawings and related records created by architects, landscape architects, engineers, surveyors, mapmakers and other professionals in building and engineering trades.
Photographic emulsion is a light-sensitive colloid used in film-based photography. Most commonly, in silver-gelatin photography, it consists of silver halide crystals dispersed in gelatin. The emulsion is usually coated onto a substrate of glass, films, paper, or fabric. The substrate is often flexible and known as a film base.
Argyrotype is an iron-based silver printing process that produces brown images on plain paper. It is an alternative process derived from the Argentotype, Kallitype, and Van Dyke processes of the 19th century, but has greater simplicity, improved image stability, and longer sensitizer shelf-life. The Argyrotype process was developed by Mike Ware in the 1990s.
Ferric oxalate, also known as iron(III) oxalate, is a chemical compound composed of ferric ions and oxalate ligands; it may also be regarded as the ferric salt of oxalic acid. The anhydrous material is pale yellow; however, it may be hydrated to form several hydrates, such as potassium ferrioxalate, or Fe2(C2O4)3 · 6 H2O, which is bright green in colour.
A heliographic copier or heliographic duplicator is an apparatus used in the world of reprography for making contact prints on paper from original drawings made with that purpose on tracing paper, parchment paper or any other transparent or translucent material using different procedures. In general terms some type of heliographic copier is used for making: Hectographic prints, Ferrogallic prints, Gel-lithographs or Silver halide prints. All of them, until a certain size, can be achieved using a contact printer with an appropriate lamp but for big engineering and architectural plans, the heliographic copiers used with the cyanotype and the diazotype technologies, are of the roller type, which makes them completely different from contact printers.
Van Dyke brown is a printing process named after Anthony van Dyck.