Calotype or talbotype is an early photographic process introduced in 1841 by William Henry Fox Talbot, [1] using paper [2] 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 καλός (kalos), "beautiful", and τύπος (typos), "impression".
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 invisible latent image had to be produced in the camera, which could be done in a minute or two if the subject was in bright sunlight. The paper, shielded from further exposure to daylight, was then removed from the camera and the latent image was chemically developed into a fully visible image. This major improvement was introduced to the public as the calotype or talbotype process in 1841. [3]
The light-sensitive silver halide in calotype paper was silver iodide, created by the reaction of silver nitrate with potassium iodide. First, "iodised paper" was made by brushing one side of a sheet of high-quality writing paper with a solution of silver nitrate, drying it, dipping it in a solution of potassium iodide, then drying it again. At this stage, the balance of the chemicals was such that the paper was practically insensitive to light and could be stored indefinitely. When wanted for use, the side initially brushed with silver nitrate was now brushed with a "gallo-nitrate of silver" solution consisting of silver nitrate, acetic acid and gallic acid, then lightly blotted and exposed in the camera. Development was effected by brushing on more of the "gallo-nitrate of silver" solution while gently warming the paper. When development was complete, the calotype was rinsed, blotted, then either stabilized by washing it in a solution of potassium bromide, which converted the remaining silver iodide into silver bromide in a condition such that it would only slightly discolour when exposed to light, or "fixed" in a hot solution of sodium thiosulphate, then known as hyposulphite of soda and commonly called "hypo", which dissolved the silver iodide and allowed it to be entirely washed out, leaving only the silver particles of the developed image and making the calotype completely insensitive to light.
The calotype process produced a translucent original negative image from which multiple positives could be made by simple contact printing. This gave it an important advantage over the daguerreotype process, which produced an opaque original positive that could be duplicated only by copying it with a camera.
Although calotype paper could be used to make positive prints from calotype negatives, Talbot's earlier silver chloride paper, commonly called salted paper, was normally used for that purpose. It was simpler and less expensive, and Talbot himself considered the appearance of salted paper prints to be more attractive. The longer exposure required to make a salted print was at worst a minor inconvenience when making a contact print by sunlight. Calotype negatives were often impregnated with wax to improve their transparency and make the grain of the paper less conspicuous in the prints.
Talbot is sometimes erroneously credited with introducing the principle of latent image development. The bitumen process used in private experiments by Nicéphore Niépce during the 1820s involved the chemical development of a latent image, as did the widely used daguerreotype process introduced to the public by Niépce's partner and successor Louis Daguerre in 1839. Talbot was, however, the first to apply it to a paper-based process and to a negative-positive process, thereby pioneering the various developed-out negative-positive processes which have dominated non-electronic photography up to the present.
Despite their flexibility and the ease with which they could be made, calotypes did not displace the daguerreotype. [4] In part, this was the result of Talbot having patented his processes in England and beyond. Unlike Talbot, Daguerre who had been granted a stipend by the French state in exchange for making his process publicly available, did not patent his invention. [4] In Scotland, where the English patent law was not applicable at the time, members of the Edinburgh Calotype Club and other Scottish early photographers successfully adopted the paper-negative photo technology. [5] In England, the Calotype Society was organized in London around 1847 attracting a dozen enthusiasts. [6] In 1853, twelve years after the introduction of paper-negative photography to the public, Talbot's patent restriction was lifted. [7]
In addition, the calotype produced a less clear image than the daguerreotype. The use of paper as a negative meant that the texture and fibers of the paper were visible in prints made from it, leading to an image that was slightly grainy or fuzzy compared to daguerreotypes, which were usually sharp and clear. [4] [8] Nevertheless, calotypes—and the salted paper prints that were made from them—remained popular in the United Kingdom and on the European continent outside France in the 1850s, especially among the amateur calotypists, who prized the aesthetics of calotypes and also wanted to differentiate from commercial photographers, [9] until the collodion process enabled both to make glass negatives combining the sharpness of a daguerreotype with the replicability of a calotype later in the nineteenth century. British photographers also brought the calotype to India, where, for example, in 1848, John McCosh, a surgeon in the East India Company, took the first image of the Maharajah Duleep Singh. [10]
Photography is the art, application, and practice of creating images by recording light, either electronically by means of an image sensor, or chemically by means of a light-sensitive material such as photographic film. It is employed in many fields of science, manufacturing, and business, as well as its more direct uses for art, film and video production, recreational purposes, hobby, and mass communication.
The following list comprises significant milestones in the development of photography technology.
William Henry Fox Talbot FRS FRSE FRAS was an English scientist, inventor, and photography pioneer who invented the salted paper and calotype processes, precursors to photographic processes of the later 19th and 20th centuries. His work in the 1840s on photomechanical reproduction led to the creation of the photoglyphic engraving process, the precursor to photogravure. He was the holder of a controversial patent that affected the early development of commercial photography in Britain. He was also a noted photographer who contributed to the development of photography as an artistic medium. He published The Pencil of Nature (1844–1846), which was illustrated with original salted paper prints from his calotype negatives and made some important early photographs of Oxford, Paris, Reading, and York.
Daguerreotype 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.
The collodion process is an early photographic process. The collodion process, mostly synonymous with the "collodion wet plate process", requires the photographic material to be coated, sensitized, exposed, and developed within the span of about fifteen minutes, necessitating a portable darkroom for use in the field. Collodion is normally used in its wet form, but it can also be used in its dry form, at the cost of greatly increased exposure time. The increased exposure time made the dry form unsuitable for the usual portraiture work of most professional photographers of the 19th century. The use of the dry form was mostly confined to landscape photography and other special applications where minutes-long exposure times were tolerable.
Louis-Jacques-Mandé Daguerre was a French artist and photographer, recognized for his invention of the eponymous daguerreotype process of photography. He became known as one of the fathers of photography. Though he is most famous for his contributions to photography, he was also an accomplished painter, scenic designer, and a developer of the diorama theatre.
The albumen print, also called albumen silver print, is a method of producing a photographic print using egg whites. Published in January 1847 by Louis Désiré Blanquart-Evrard, it was the first commercial process of producing a photo on a paper base from a negative, previous methods - such as the daguerreotype and the tintype - having been printed on metal. It became the dominant form of photographic positives from 1855 to the start of the 20th century, with a peak in the 1860–90 period. During the mid-19th century, the carte de visite became one of the more popular uses of the albumen method. In the 19th century, E. & H. T. Anthony & Company were the largest makers and distributors of albumen photographic prints and paper in the United States.
An enlarger is a specialized transparency projector used to produce photographic prints from film or glass negatives, or from transparencies.
The ambrotype, 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.
A tintype, also known as a melanotype or ferrotype, is a photograph made by creating a direct positive on a thin sheet of metal, colloquially called 'tin', coated with a dark lacquer or enamel and used as the support for the photographic emulsion. It was introduced in 1853 by Adolphe Alexandre Martin in Paris, like the daguerreotype was fourteen years before by Daguerre. The daguerreotype was established and most popular by now, though the primary competition for the tintype would have been the ambrotype, that shared the same collodion process, but on a glass support instead of metal. Both found unequivocal, if not exclusive, acceptance in North America. Tintypes enjoyed their widest use during the 1860s and 1870s, but lesser use of the medium persisted into 1930s and it has been revived as a novelty and fine art form in the 21st century. It has been described as the first "truly democratic" medium for mass portraiture.
Erotic photography is a style of art photography of an erotic, sexually suggestive or sexually provocative nature.
The history of photography began with the discovery of two critical principles: The first is camera obscura image projection, the second is the discovery that some substances are visibly altered by exposure to light. There are no artifacts or descriptions that indicate any attempt to capture images with light sensitive materials prior to the 18th century.
Hand-colouring refers to any method of manually adding colour to a monochrome photograph, generally either to heighten the realism of the image or for artistic purposes. Hand-colouring is also known as hand painting or overpainting.
Thomas Wedgwood was an English photographer and inventor. He is most widely known as an early experimenter in the field of photography.
The following outline is provided as an overview of and topical guide to photography:
The salt print was the dominant paper-based photographic process for producing positive prints from 1839 until approximately 1860.
Paper texture effects in calotype photography limit the ability of this early process to record low contrast details and textures. A calotype is a photographic negative produced on uncoated paper. An important feature is that a relatively short exposure in a camera produces a latent image that is subsequently made visible by development. Then positive images for viewing are obtained by contact printing. This technique was in use principally from 1840 into the 1850s, when it was displaced by photography on glass. Skilled photographers were able to achieve dramatic results with the calotype process, and the reason for its eclipse may not be evident from viewing reproductions of early work.
Peter Wickens Fry was a pioneering English amateur photographer, although professionally he was a London solicitor. In the early 1850s, Fry worked with Frederick Scott Archer, assisting him in the early experiments of the wet collodion process. He was also active in helping Roger Fenton to set up the Royal Photographic Society in 1853. Several of his photographs are in the Victoria and Albert Museum in London.
Samuel Buckle was an early English photographer.
John McCosh or John MacCosh or James McCosh was a Scottish army surgeon who made documentary photographs whilst serving in India and Burma. His photographs during the Second Anglo-Sikh War (1848–1849) of people and places associated with the British rule in India, and of the Second Burmese War (1852–1853), count as sufficient grounds, some historians maintain, to recognise him as the first war photographer known by name. McCosh wrote a number of books on medicine and photography, as well as books of poetry.
