The cyanotype was developed by John Herschel in 1842 and became his most commercially successful photographic process. It requires only two chemical compounds: ferric ammonium citrate and potassium ferricyanide, which produce Prussian blue, an intense blue pigment used by artists before photography. The two solutions are created separately and mixed together before sensitizing the paper. The iron in the mixture is the light sensitive property, so once the mixture is brushed onto the surface of the paper, it is ready to be exposed. Fixing the image requires only water, and although the pigment is highly insoluble in water, much of it is lost during processing. Nonetheless, the water brings out the rich blue color and makes the image permanent.
The cyanotype, unfortunately, was not terribly popular in Herschel's time. It had slightly limited tonal range and the strong Prussian blue color wasn't approved of for portraits or other popular photographic subjects. Proper exposure could require 30 minutes or more and the "bleeding" of the Prussian blue during fixing can stain the highlights. The low cost and availability of the chemicals, however, made it easy for amateurs to use, and the cyanotype was able to survive into the 20th century.
Ware, Mike. Cyanotype: The history, science and art of photographic printing in Prussian blue Schaaf, Larry J. Sun Gardens: Victorian Photograms by Anna Atkins
We created solution A with 100ml of distilled water and 25g of ferric ammonium citrate (green) and solution B with 100ml of distilled water and 10g of potassium ferricyanide. The two solutions were mixed 1:1. The solutions, however, must be stored separately when not being used.
The VanDyke brown print is an iron-silver process based on the argentotype invented by John Herschel in 1842. The process gets its name from its deep brown color that is similar to that of the pigment used by Flemish painter Van Dyck.
Three solutions were made with distilled water: one with ferric ammonium citrate, another with silver nitrate, and the last with tartaric acid. The solutions were mixed together while stirring. The liquid was a pea green color and occasionally needed stirring before applying to our 100% cotton rag paper.
To sensitize our paper, we simply brushed on coat of the mixture onto the paper. We then exposed our paper with a negative out in the sun for about 5 minutes.
The albumen print was invented in 1850 by Louis Desire Blanquart-Evrard and was the dominant positive print process in the second half of the 19th century. Although Blanquart-Evrard is credited with the invention of the process and presented it to the French Academy of Sciences in 1850, many amateurs had experimented with and wrote about albumen prints before his announcement.
The term "albumen" refers to the mixture of egg white and salt coat that was applied to the paper before being sensitized. The layer of egg covered the rough and porous surface of the paper and resulted in prints with greater detail and a glossy finish, which could be increased by adding more coats of albumen. The albumen print, like the salted paper print, is a printed-out process. It has a warm reddish-brown color due to the small colloidal silver particles of the image. Because the albumen is not the light sensitive element, papers could be coated and set aside for printing at a later date, a characteristic that led to the sale of already coated paper and made photography available to the masses.
Blanquart-Evrard's original formula for albumen consisted of egg whites and salt. 25% by weight of a saturated salt solution was added to egg whites that were beaten to a froth and allowed to sit overnight. The paper was floated on top of the mixture for a minute and hung to dry. The paper could then be sensitized with a silver solution, which reacted with the salt in the albumen to produce silver chloride. A hype solution fixed the image after exposure.
There were some difficulties with albumen prints, such as impurities and inconsistency among paper, the tendency of prints to fade or shift color, the possibility of the albumen coating cracking as it ages, and foxing, or brown age spots on the paper medium. Improvements were made, however, as experimenters worked with fermenting the egg whites, often by adding acid, to achieve glossier coats and finer detail. Experimenters also developed alkaline gold toning, which gave a wider range of image colors and increased durability and resistance to fading.
An albumen print with alkaline gold toning
The new photographic technology of stereographs and cartes de visite increasted the demand for albumen paper. The fine detial of the paper made it ideal for images that would provide the illusion of three-dimensional reality in the stereograph, and the ease of use and accessibility of albumen allowed "card pictures" to be made cheaply with images of people, places, and things.
An albumen carte de visite (left) and stereocard (right).
Elizabeth Goins, first draft of albumen chapter Reilly, James M. The Albumen and Salted Paper Book: The history and practice of photographic printing, 1840-1895. Light Impressions Corporation. Rochester, 1980.
The albumen mixture we used was made by the class with three simple ingredients:
500ml of egg whites saved after separating eggs
3ml of vinegar
7.5g of salt
The mixture was shaken until frothy and left to sit for a couple days.
The albumen was strained through a cheesecloth before we coated the 100% cotton rag paper by letting the pieces float on the solution, which needed to be free of air bubbles. Each person made two pieces of paper with one coat of albumen and two pieces with two coats of albumen.
For the two coat pieces, the first coat was left to dry by hanging the paper by the corner before being dipped in an alcohol bath, dried, and coated again. This gave the papers a glossier finish. The paper was then given a layer of light sensitive silver nitrate solution.
We exposed the papers for about 7 minutes with green negatives made outside of class.
The papers were put through washes and fixed with hypo.
Unfortunately, my albumen prints turned out very streaky. The one-coat (top) was underexposed and lightened considerably during fixation. The two-coats (bottom) didn't produce any image.
My arrowroot image (top) was streaky also, but a there is a very faint image. The gelatin print (bottom) was my most successful out of the three processes.
I'm disappointed that I was unable to make a successful albumen print. I think the biggest factor is the need to improve my silver nitrate solution coating technique, which should reduce the streaking. It would probably also help to increase my exposure time. Despite the unsuccessful prints, it was interesting working with eggs, and although it's faint, the one-coat albumen print has an interesting texture and look with little circles where air bubbles were in the albumen mixture.
I removed the step tablet from the anthotype that was in the window for a month. It has lightened considerably and is definitely the most faded of the three. The separation between the steps is still not apparent but there is a definite difference in the lighter end, which would be the highlights, and the darker end, which would be the shadows.
(from the left) The 1 week, 2 week, and 1 month anthotypes. Based on my results from this experiment, I assume that using a negative would require at least a month exposure and that the image would have a range of shadows and highlights but no detail between them.
