My Favorite Alternative Photographic Processes
In 1851, Frederick Scott Archer introduced a wet plate process, sometimes referred to as the collodion process after the carrier material used. The process is simple: a bromide, iodide, or chloride is dissolved in collodion (a solution of pyroxylin in alcohol and ether). This mixture is poured on a cleaned glass plate, which is allowed to sit until the coating gels but is still moist. The plate is then placed in a silver nitrate solution, which converts the iodide, bromide, or chloride to silver iodide, bromide or chloride. Once the reaction is complete, the plate is removed from the silver nitrate solution and exposed in a camera while still wet. The plate loses sensitivity as it dries, requiring it to be coated and sensitized immediately before use. It must also be developed while still moist, using a solution of iron sulfate, acetic acid and alcohol in water.
“Collodion process” is usually taken to be synonymous with the “collodion wet plate process”, a very inconvenient form which required 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. Although collodion was normally used in this wet form, the material could also be used in humid (“preserved”) or dry form, but at the cost of greatly increased exposure time, making these forms unsuitable for the usual work of most professional photographers—portraiture. Their use was therefore confined to landscape photography and other special applications where minutes-long exposure times were tolerable.
The sensitivity of silver halides to actinic light is the underlying principle behind most types of 19th century photographic processes (Daguerreotypes, Ambrotypes, Calotypes that use paper negatives, and wet and dry plates) as well as modern 20th century photographic film processes.
Platinum & Palladium
Also called platinotypes, are photographic prints made by a monochrome printing process that provides the greatest tonal range of any printing method using chemical development. Platinum prints are made by photographers and favored by collectors because of their tonal range, the surface quality and their permanence. A platinum print provides a broad scale of tones from black to white. The platinum tones range from warm black, to reddish brown, to expanded mid-tone grays that are unobtainable in silver prints. Unlike the silver print process, platinum lies on the paper surface, while silver lies in a gelatin or albumen emulsion that coats the paper. As a result, since no gelatin emulsion is used, the final platinum image is absolutely matte with a deposit of platinum (and/or palladium, its sister element which is also used in most platinum photographs) absorbed slightly into the paper. Platinum prints are the most durable of all photographic processes. The platinum group metals are very stable against chemical reactions that might degrade the print—even more stable than gold. A greatly decreased susceptibility to deterioration compared to silver-based prints due to the inherent stability of the process and also because they are commonly printed on 100% rag papers.
In photography, the palladiotype is a less-common variant of the platinotype. The process came into greater use after World War I because the platinum used in the more-common platinotype quickly became too expensive. Due to the rising cost and the consequent shortage of commercial platinum paper, photographers tried to replace the platinum with the much cheaper palladium which gave similar effects. The cost of this metal, however, also started to rise and eventually around 1930 the process was abandoned in favor of more-economical processes. Though, in recent years, a handful of photographers have taken up the art of mixing platinum and palladium and printing fine art prints with those chemicals, despite its cost.
The salted paper technique was created by British photographer William Henry Fox Talbot. He called his negative process calotype printing, while the salt print process was used for making positive prints from the calotype negatives. They both employ a technique of coating sheets of paper with silver salts, but the calotype process differs slightly in chemicals used in the sensitization procedure, and uses an extra ‘accelerator’ step, immediately prior to exposure of the sensitized paper.
is a photographic printing process that produces a cyan-blue print. Engineers used the process well into the 20th century as a simple and low-cost process to produce copies of drawings, referred to as blueprints. The process uses two chemicals: ammonium iron(III) citrate and potassium ferricyanide.
The English scientist and astronomer Sir John Herschel discovered the procedure in 1842. Though the process was developed by Herschel, he considered it as mainly a means of reproducing notes and diagrams, as in blueprints. It was Anna Atkins who brought this to photography. She created a limited series of cyanotype books that documented ferns and other plant life from her extensive seaweed collection.Atkins placed specimens directly onto coated paper, allowing the action of light to create a silhouette effect. By using this photogram process, Anna Atkins is regarded as the first female photographer.
The Vandyke brown print is based on the first iron-silver process, the argentotype, invented in 1842 by the English astronomer, Sir John Herschel. Both processes utilize the action of light on ferric salts and their chemistry is very similar. The Vandyke process gets its name from its similarity in color to the deep brown pigment used by the Flemish painter Van Dyck.
Vandyke brown prints are very simple and economical to make, with the sensitizer consisting of three readily available chemicals. Clearing is carried out in water and fixing is done in a weak solution of hypo.
Patented in 1889 by W. W. J. Nicol, 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. The use of ferric oxalate allows for both extended shadow definition (higher DMAX) and contrast control.
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.
The albumen print, also called albumen silver print, was invented in 1850 by Louis Désiré Blanquart-Evrard, and was the first commercially exploitable method of producing a photographic print on a paper base from a negative. It used the albumen found in egg whites to bind the photographic chemicals to the paper and became the dominant form of photographic positives from 1855 to the turn 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 the Albumen photographic prints and paper in the United States.