The numerous photographic processes employed in the 19th century may seem daunting to the uninitiated. Indeed, what follows is merely an introduction. Further information about 19th and early 20th century processes can be gleaned from the bibliographic references listed at the end of this section. It might be reassuring, however, to know that by far the greatest proportion of 19th century photographs made prior to 1885 were simply albumen prints made from glass negatives.
Nineteenth century prints were seldom enlarged from smaller negatives. The surviving contact prints of that era also typically possess very broad tonal ranges compared with much modern photography. These factors are responsible for the striking beauty of much 19th century imagery that can be a revelation to observers encountering the field for the first time. The overwhelming majority of 19th century negatives have long ago been destroyed so that cases of much later prints produced from early negatives is rarely an issue.
Invented by L.J.M. Daguerre in the late 1830s, the daguerreotype was the first photographic process to be publicly announced to the world. This historic event took place in Paris in 1839, the same year as W.H. Fox Talbot was to later announce his much different photogenic drawing process. The daguerreotype was produced on a silvered copper plate that was made sensitive to light by iodine fumes and, after exposure in a camera, then developed by mercury vapour. Each plate is unique, there being no negative. The image from a fine daguerreotype can be impeccably sharp with great tonal range, though the image can be difficult to view due to the highly polished silver surface of the plate. Daguerreotypes, which can be damaged by the slightest touch, are usually housed behind glass in cases or frames. Examples were common until about 1856, generally dying out by the early 1860s.
Ambrotype was a term invented in America to describe a positive glass process using collodion (gun cotton dissolved in ether). The negative 'wet collodion' technique, invented by Frederick Scott Archer in 1851, was an important development in photographic history, the glass negative providing very sharp detail for the first time in a practical process. Utilising an underexposed collodion negative that was, subsequently, merely painted black on the back of the glass or, alternatively, backed by a piece of black paper or cloth, created a positive image in practice. This ambrotype or collodion positive was put into a leather case or frame in the same way as a daguerreotype, but was far easier to view as it was on glass rather than highly reflective silver and was a true positive rather than a postive and negative at the same time. The ambrotype process thrived from 1852 to 1890.
The 'calotype' process, announced in 1841, was the first practical process for making positive prints from negatives. It quickly followed, and was an improvement on, William Henry Fox Talbot's invention of the photogenic drawing process in the 1830s. Talbot's improved negatives were used to produce positive salt prints (or salted paper prints) by soaking a sheet of plain writing paper in a solution of salt and then sensitising one side of the paper with silver nitrate. The paper was then put into contact with a negative and printed out in a printing frame in sunlight. When the print was deemed to be sufficiently dark, it was fixed, usually with hyposulfite of soda (hypo), washed thoroughly and dried.
Salt prints of the 1840s-50s were made from paper negatives (the 'calotype' and 'waxed paper process' were the most common) or from glass negatives (the 'wet collodion' process was the most common). Salt print positives made from calotype paper negatives are often loosely referred to by the name of the negative process, i.e., calotype.
A salt print has a completely matt surface with the photographic image appearing to be slightly sunken into the fibres of the paper. When a paper negative, in particular, is used to make a salt print, the resultant print possesses a diffuse artistic quality that was admired by painters in the 19th century and is prized today by many collectors and museums. Salt prints were common from approximately 1840-55, dying out, except for the odd revival, in around 1860.
The albumen print, invented by Louis-Desiré Blanquart-Evrard in 1850, was essentially the same as the salt print process, but before sensitisation, the paper surface was coated with a film of albumen (egg white). This gave the resulting print a sheen that made the image appear to be resting on the surface of the paper. Albumen prints were often made utilising glass negatives (most often 'wet collodion'), giving the image a sharpness of definition not usually present in salt prints. Albumen prints were common from 1850-1900 and were the most dominant process between 1856 and1885.
These two terms describe the often confusing range of very low gloss prints, produced usually during the 1850s, which have neither quite the classic matt characteristics of a salt print nor the higher sheen of an albumen print. Both these types of prints display a much lower sheen than a normal albumen print but a higher sheen than a salt print. A non-matt salt print most closely retains the aesthetic 'feel' of a salt print in that it has the image structure largely sunken into the fibres of the paper. A light albumen print has the aesthetic 'feel' of an albumen print with the image appearing to be perched on the surface of the paper.
The woodburytype was a photomechanical process which used pigmented gelatin to form a gelatin mould which could subsequently be printed onto paper. Invented by Walter Woodbury in 1864, the woodburytype prints had to be mounted on to card before they were usable. The quality of this process could be extremely high, often producing beautiful impressions, despite the fact that the woodburytype is not technically a true photograph, the final print being mechanical. Woodburytypes were commonly used for book illustration from 1870 until about 1900.
Many variations of carbon printing were invented from the 1850s onwards, but Joseph Wilson Swan patented the most practical process in 1864. Like the woodburytype, the process depends on a complex of gelatin with added potassium bichromate being sensitive to light. As there are no light-sensitive silver salts in the final print, carbon prints are considered “permanent”. Like woodburytypes, with which they are sometimes confused, the prints are usually very dark and there is often a slight relief to the print. Also, like the woodburytype, prints could be produced in different hues. Carbon prints were common between 1870 and 1910.
The platinum print or platinotype invented by William Willis in 1873 was another non-silver process which depended on the light-sensitivity of certain iron salts. This quite stable process produced a print characterised by a matt surface and, usually, silvery-grey mid-tones. Platinum prints were common from 1880 to 1920, with the delicate shades of grey inherent in the process being favoured by 'art' photographers. Originally not an expensive process, the high price of platinum led to it becoming rarely used after 1920, except by a few fine art photographers.
A photomechanical process invented by W.H. Fox Talbot in the 1850s and improved by Karl Klic in 1879, photogravure is a mechanical method of reproducing photographs. A copper plate is first etched by the use of a gelatin relief image that has been produced photographically. The resultant etching is then inked and printed on a press. The fine etching-like qualities of good examples were often preferred by 'art' photographers and were commonly used between the years 1890 and 1915. Prominent examples of photogravure can be seen in books by P.H. Emerson and in many plates published in Alfred Steiglitz's groundbreaking American journal, Camera Work. The use of photogravure has continued to the present.
This term refers to an array of processes, such as those using silver-chloride and silver-bromide developing-out paper and gelatin-bromide printing-out paper. The surface of this family of prints might vary from highly glossy to completely matt. These prints generally arrived after the albumen era, though also overlapped with it, gelatin silver papers beginning to replace albumen as the dominant process by the 1890s. Many gelatin silver prints were made using the newer gelatin dry plate negatives that began to replace the slower wet collodion process by around 1885. It should be noted that gelatin silver prints can be indistinguishable from the less common collodion prints of the same period. Gelatin silver prints were commonly used between 1885 and 1920.
Invented by Sir John Herschel in 1840, this process depended on the light sensitivity of iron salts. The so-called “blueprint” process consisted of a metal complex known as “Prussian blue”. Used sparingly from the 1840s, the cyanotype was only really popular during the 1890s, particularly for amateur snapshot photography in America.
Collodion-chloride printing-out paper came in both glossy and matt versions and was available roughly from the late 1880s through the 1920s. Both versions can easily be mistaken, respectively, for glossy or matt gelatin silver prints. The matt version of collodion paper can often also resemble the platinum print.
This process, invented by Alphonse Poitevin in 1855, was the first photolithographic process. Collotypes, though often very beautiful, are photomechanical and are not true photographs. The process exploited the effect of light on dichromated gelatin to create a residual 'greasy ink' which could be transferred onto paper and other surfaces. Versions of this process have been developed in France as Phototype and Phototypie and it is known in Germany as Lichtdruck or an improved version called Albertype. The Autotype Company of England labeled its collotypes as 'Autotypes'. This was confusing as they tended to identify their carbon prints under the same name. The process became very popular from the 1870s for book illustration and is still used today. An early manual for painters suggested that artists use collotypes underneath paintings as secret tracing aids since the greasy ink became indistinguishable afterwards from the pigments utilised in certain painting techniques. Under high magnification, collotypes may be identified by a pattern of 'reticulation'.
This colour photolithographic process, perhaps based on Léon Vidal's photochrome process of the 1870s, was invented by the firm of Orel Füssly of Zurich and patented in 1898. A photochrom print was a somewhat surreal bright-coloured mechanical photographic print, as opposed to a true colour photograph. Specimens frequently have a gold-embossed P.Z. (Photochrom Zurich) at the lower edge of a print.
The autochrome process, invented in 1904, was the first practical colour photographic process, and was developed in France by the brothers, August and Louis Lumière. Becoming commercially available in 1907, a glass plate was coated with tiny grains of potato-starch which were dyed green, red and blue. The potato-starch grains acted as tiny colour filters and were covered with a gelatin-bromide panchromatic silver emulsion. The finest examples of the autochrome process present bright primary colours in a grainy, but highly atmospheric image, on a unique glass transparency. This romantic soft-focus imagery fitted in well with the prevailing pictorialist ethos of the early years of 20th century photography.
Unless otherwise specified, all prints are believed to be from glass negatives. The date given indicates the approximate date the negatve was produced. Prints were made, unless otherwise indicated, during the same period in which they were commonly issued by the original photographer or studio. The exact date of printing for 19th century photographs is often difficult to ascertain. The period of printing from a negative is usually only for a few years after the negative was made, but in the cases of studios with greater longevity, prints could have been made over a longer period and there is not always a method of determining the exact printing date. In cases where more than one distinct period of printing is known, for example, when a second photographer re-issued the prints of an earlier photographer, this is indicated.
For further information on early processes, see the following works:
Gordon Baldwin, 1991, Looking At Photographs. A Guide To The Technical Terms. Malibu & London: The J. Paul Getty Museum & British Museum Press, 1991
Brian Coe and Mark Haworth-Booth, A Guide to Early Photographic Processes, London: The Victoria & Albert Museum & Hurstwood Press, 1983
Ken Jacobson, 'Problematic Low-Sheen Salt And Albumen Prints', History of Photography An International Quarterly, London, New York & Philadephia: Taylor & Francis, 1991, Vol. 15, No. 4, pp. 287-294
Luis Nadeau, Encyclopedia Of Printing, Photographic, And Photomechanical Processes, Fredericton, New Brunswick: Atelier Luis Nadeau, 1994
James M. Reilly, Care And Identification Of 19th-Century Photographic Prints, Rochester, N.Y.: Eastman Kodak Company 1986