The history of photography is deeply rooted in science. Nature can be represented by photography in ever increasing detail, but photography is not natural. It is an artefact, a revolutionary invention that has earned its place in the pantheon of modernity. Besides optics, the branch of physics that has enabled camera manufacturers to produce increasingly accurate lenses, the application of chemistry has played an important role in the development of the medium. And it is this chemical aspect that has an astounding connection to the natural world.
One of the early pioneers of photography, Henry Fox Talbot, was granted a patent in 1841 for his trailblazing Calotype process. One of the key descriptions in his patent is surprisingly poetic:
“with this liquid I wash the paper all over with a soft camel hair brush, I then hold it before a gentle fire, and in a short time (varying from a few seconds to a minute or two), the image begins to appear on the paper. Those parts of the paper on which light has acted the most strongly become brown or black, while those parts on which light has not acted remain white.”(1)
One of the ingredients that is used to prepare this liquid is gallic acid, a compound harvested from the galls of oak trees. Talbot not only uses this compound to prepare photosensitive paper but also for enhancing the photographic images after exposure. This technique would later simply be called ‘developing’. The use of organic compounds in photographic developer has lived on ever since, but this fact has been often obscured by technical language.
In James Riddick Partington’s encyclopaedic The History of Chemistry the German chemist Friedrich Wöhler, a contemporary of Talbot, is cited: “organic chemistry appears to me like a primeval forest of the tropics, full of the most remarkable things”. This is followed by a striking observation by the author and historian: “The entry into the dark forest, and the clearing of the undergrowth, was a task to which chemists first seriously applied themselves in the period at which we have now arrived [1835], and the discoveries were destined to alter the whole aspect of chemistry.”(2)
This ‘clearing of the undergrowth’ suggests a reorganisation of the natural world, streamlining something that is too chaotic to be useful. A similar desire to control complex chemical reactions can be found in a manual concerned with photochemical formulae published by Kodak in 1949: “the purity, strength, and uniformity of the chemicals, the quantity of each used, and the manner in which they are combined, are of the utmost importance in achieving results of uniformly high quality.”(3) But remarkably, Kodak’s D1 developer, one of the earliest commercially available photographic developers, contains pyrogallol, an organic compound prepared by heating Talbot’s gallic acid. In 1970 the company filed another patent based on organic chemistry, aiming to improve the solution that was used in continuous processors. This new developer contained hemlock tannin polymer, an organic compound harvested from the bark of Pine Trees.(4)
The key to all of the above examples is a molecule that many plants have in common. This ‘secret knowledge’ was disclosed in 1995 during a class under the supervision of Dr Scott Williams at the Rochester Institute of Technology. By no coincidence this institute shares its location with Kodak’s headquarters. Williams writes in his now famous paper: “Coffee contains just about every type of molecule known to nature, including proteins, lipids and carbohydrates, but that “go-juice” that many of us cannot do without also contains a group of molecules known as phenols.”(5) This coffee based developer is now known as Caffenol and is used by thousands of amateur and professional photographers around the world. Numerous blogs, leaflets and books have appeared, dedicated to this method. More traditionally minded photographers have recommended the formula for its simplicity, low cost and accuracy while experimental photographers and filmmakers have praised its non-toxic, aromatic and aesthetic qualities. Besides instant coffee, the formula is based on vitamin C and soda crystals. Vitamin C acts as a second developing agent providing so called ‘superadditivity’. Soda crystals are added to lower the acidity of the solution and further enhance the chemical process. Fresh variations can be assembled, by replacing the coffee with mint, flowers, seaweed or beer. Such ‘eco-processing’ methods have inspired artists to look at the medium anew, making use of the diverse tonalities that these developers can produce.
After having a close look at Williams’ paper in 2016, I hypothesized that it might be possible to use intact leaves or flowers as mark makers. I began soaking plants in a deconstructed version of his formula, bringing the infused leaves in contact with photographic emulsion. This method allowed me to tap into the agency of the plants, activating the therein contained polyphenols. These chemical traces or ‘phytograms’(6) not only reveal the outline of the plant but also the vascular tissue and in some cases the individual cells. It is a process that is difficult to control as it is dependent on the particular photographic material, temperature, available light, the chemical mixture and, most importantly, the concentration and distribution of polyphenols in each particular plant.
Instead of ‘clearing the undergrowth’ in the dark forest of organic chemistry, the aim here is to celebrate the remarkable things that occur when natural processes are incorporated in the art of photography. As demonstrated, photographic developers have contained organic compounds throughout the history of the medium. But instead of obscuring this fact by technical language, it is timely to bring this ‘wild’ aspect centre stage. Let the weeds grow apace and flourish!
Bibliography:
1) Talbot, William Henry Fox: Photographic Pictures, UK Patent 8842, filed 29 July 1841, and issued 7 August 1841: 3.
2) Partington, James Riddick (1964) A History of Chemistry Vol. 4, London: Macmillan: 233.
3) Kodak (1949): Kodak Chemicals and Formulae. London: Kodak.
4) Russel, Harold D. and Amering, Charles F.: Photographic Developing Process Utilizing Hemlock Tannin Polymer, US Patent 3,515,556, filed 1 August 1967 and issued 2 June 1970.
5) Scott Williams & Technical Photographic Chemistry Class, A Use for that last Cup of Coffee: Film and Paper Development DCCT: September/October 1995.
6) Doing, Karel (2020) Phytograms: Rebuilding Human-Plant Affiliations, Animation, 15(1): 22-36.
Karel Doing, Timelapse (Phytogram) 2019
Phytogram 