Glossary of Photographic Terms

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  Albumen Print
  Albumen prints were invented in 1850 by Louis-Desiré Blanquart-Evrard and popular until approximately 1890. The prints are always in black and white, although they may be toned to a monochrome hue (the finished prints range in color from reddish to purplish brown). If the print has deteriorated, the highlights can look yellowish. The word “albumen” references the use of egg white to prepare the paper for printing.
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  Ambrotype
  Ambrotypes were developed as negative images on glass. When backed with an opaque coating, the negative then appears to be a positive image, thus making each ambrotype a unique object. (For an example of an ambrotype with part of its backing removed, thus revealing the negative surface) Ambrotypes were used primarily for portraiture. Ambrotypes are similar to daguerreotypes in their size and packaging; however, they are easier to tint, faster as well as cheaper to make than daguerreotypes, thus replacing daguerreotypes in the 1850s. They were later replaced by tintypes and carte-de-visites in the 1860s.
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  Calotype
  The calotype was invented by William Henry Fox Talbot in 1840, patented in 1841 and remained popular until the early 1850s. It has been identified as the direct ancestor of modern photograph because of its use of both a positive and negative. Because of the existence of the negative, multiple prints could be made (unlike the daguerreotype and ambrotype which was a singular, unique object). Because of the use of a paper negative, the positive image can often appear a bit fuzzy due to the presence of paper fibers in the negative. The term “calotype” was coined by Talbot from the Greek kalos (beautiful) and Latin typus (image).
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  Carbon Print
  Several people are credited with the development of the carbon print (patented by Alphonse Louis Poitevin in 1855; improved by John Pouncy in 1858; additional developments in process and printing papers by Joseph Wilson Swann in 1864). Carbon prints derive their name from the use of carbon particles mixed with gelatin and bichromate to from the emulsion. Through the use of carbon and the removal of all chemicals in the washing process, carbon print images are permanent. They are also rich in tonal scale, from black to a deep rich brown. Carbon prints were popular between 1870 and 1910.
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  Chromogenic Color Print
  A chromogenic color print, otherwise known as a “C-print,” is a color print made from either a color transparency or color negative. The print paper has at least three layers of emulsion – each sensitized to a different color wavelength. Thus, once the negative image is exposed to the paper, each color layer records different information.
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  Cliché Verre
  Cliché Verre is a French term which refers to the use of a piece of glass as a surface for drawing. Typically this drawing is done on a glass plate coated with an opaque layer (such as paint or smoke) which is then scratched through. Once the image has been drawn, the glass plate is then used as a negative to print onto light-sensitive paper. The process was used by William Henry Fox Talbot as early as 1835, and continues to be used today.
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  Contact print
  A contact print is made by interfacing the negative of any material with printing paper, and exposing the two to light (either natural or artificial). The resulting print is the exact same size as the negative.
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  Cyanotype
  Invented by Sir John Herschel in 1842, the cyanotype process involves brushing light-sensitive solutions onto a sheet of paper. The item to be reproduced – either a drawing, negative or three-dimensional object (such as a plant specimen) – is then placed upon the sheet and exposed to direct sunlight. After a long exposure (approximately fifteen minutes), the impression forms on the paper; wherever the object blocked the light, the paper will remain white. When washed with water, through an oxidation process, the paper turns blue; the name “cyanotype” references this brilliant blue color (cyan). Early architectural drawings used a duplication similar process – hence the term “blueprints.”
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  Daguerreotype
  The daguerreotype’s invention by Louis-Jacques-Mandé Daguerre was announced in 1839 and was popular until the 1850s, when it was replaced by the ambrotype. The direct-positive images are highly detailed and were most popularly used for portraits. Because of the delicate nature of the daguerreotype’s surface, the images were stored in protective cases made up of a metal mat, a glass cover, and book-like binding made of leather or plastic and lined with colored velvet.
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  Dye transfer print
  A method of making color prints or transparencies that gives control of color balance and contrasts. Dye transfer prints are longer lasting than color prints, though like all color images they are subject to fading in strong light. The original color image is divided into its primary colors by making separation negatives (three black and white negatives individually exposed through red, green and blue filters). The negatives are used to make separation positives, or matrices, which are gelatin relief images that soak up dyes in proportion to the thickness of the gelatin. The dye-soaked images are transferred to exact alignment onto another sheet to reproduce the original color image.
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  Gelatin silver print
  Gelatin silver prints are prints on papers coated with a gelatin which contains silver salts. The paper is used to make black-and-white prints. The paper was first invented in 1873, but not in general use until the 1880s, and is still generally in use today. Because of the variety of papers on the market, the tones can range from a neutral black to a bluish black or a brownish black.
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  Gum bichromate print
  The gum bichromate process was favored in the later-portion of the nineteenth century for the level of control over to the final print offered to the artist. A sheet of paper was brushed with a coating of gum arabic and potassium bichromate, allowed to dry, and then exposed to a negative. Because the gum arabic hardened in accordance to the amount of light exposure, the artist could either brush or wash away portions of the gum that remained, thus altering the contrast of the print. The resulting prints often resemble crayon or charcoal drawings because of the broad areas of diffused detail.
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  Hand coloring
  Hand coloring is a method of applying color to the surface of a black and white photograph utilizing watercolor, paint, or dye. It has been in use since the time of daguerotypes.
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  Photogravure
  A means of printing a photographic image by the intaglio process, developed in the 1850s and used through the mid-twentieth century. The photographic negative (which may be of an artist's drawing) is projected onto a sensitized gelatin emulsion or carbon tissue that is transferred to a copper plate. After washing the plate areas that correspond to the image on the negative are dissolved and the plate can be bitten by acid as in routine etching. In hand photogravure, which is most commonly used in printmaking, the copper plate is first prepared for aquatint etching. The end result can closely resemble a traditional linear etching or soft ground etching.
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  Platinum Print
  Platinum prints were invented in 1873 by William Willis, became commercially available in 1878, and was widely in use until the 1920s. Platinum prints have subtle tonal ranges, usually silver-gray.
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  Polaroid™ print
  Polaroid™ is a brand of camera and film which produces self-developing pictures. Available for commercial use by 1950, Polaroid™ instant film remained popular through the remainder of the twentieth century, and was discontinued from production in 2008.
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  Stereograph
  Especially popular during the Victorian period, stereograph images are taken with a two-lens camera. The resulting print is a double photograph of the same image, and when viewed through a stereoscope, a three-dimensional view of the photograph appears (thereby approximating human binocular vision). The popular children’s toy, the View-Master, is another example of such technology.
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  Tintype
  Tintypes were patented by William Neff and his son Peter in 1856 and were popular through the end of the nineteenth century. A tintype is made up an iron surface upon which a light-sensitive emulsion is applied and then exposed in a camera (hence the term “tintype” is actually a misnomer). Tintypes quickly replaced ambrotypes because of the cheap cost of the metal; in addition, tintypes appealed to consumers because they were not fragile and thus could be sent through the mail (unlike images on glass such as ambrotypes or daguerreotypes).
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  Woodburytype
  The Woodburytype was patented by Walter Bentley Woodbury in 1864 and was popular until around 1900. It is a photomechanical means of reproducing a photograph. The resulting prints are often highly luminous in tone. Woodburytypes were often used to illustrate fine books of the late nineteenth century.

• Baldwin, Gordon. Looking at Photographs: A Guide to Technical Terms (Los Angeles: The J. Paul Getty Museum), 1991.
• Gernsheim, Helmut and Alison, The History of Photography (New York: Grosset & Dunlap),1969.
• Jeffrey, Ian, Photography: A Concise History (London: Thames and Hudson) 1981.
• Newhall, Beaumont. The History of Photography (New York: Museum of Modern Art), c.1982.
• Szarkowski, John, Looking at Photographs (New York; distributed by New York Graphic Society, Greenwich, CT) 1973