What are chicken eggs doing in analog photography and why albumin? The second question can be explained quickly, because albumin is also found in hen's eggs (protein) and in human and animal blood.
First a little photographic history!
From around 1840 the salt print gradually replaced the daguerotype and at this time it was possible for the first time to make an unlimited number of prints from a photograph. A sensation because the daguerotype could only be used to produce unique items. But the salt sprint had major weaknesses! He lacked the brilliance and sharpness of the daguerotype. The salt prints looked dull, soft and washed out. The problem was quickly recognized, which was due to the fact that the chemicals / silver halides used penetrated too deeply into the photographic paper. In 1850, the Frenchman Desire Blanquart-Evrard developed a way of keeping the photographic image on the surface of the paper. The paper was coated with albumin and could also come up with brilliance and sharpness, the daguerotype.
Under the heading “handmade paper”, my main aim was to create unique items. Here it quickly became apparent that the handmade paper that was produced in-house sometimes behaves like blotting paper in photo printing. The ink was soaked up by the paper and penetrated too deeply into the paper. So it occurred to me to coat the paper with albumin as well to ensure that the ink is held on the surface. And the first attempt also succeeded; a sensation for me.
Before I could start the experiment, however, I first had to produce photographic albumin. I would like to describe this procedure below:
6 eggs or enough for 250 ml egg white,
7.5 g salt,
7.5 ml of distilled water,
1 ml 28% acetic acid,
7.5 g sodium citrate (optional preservative),
1 drop of AdoFlo (optional).
Separate the egg white from the yolk and make sure that no egg shell or hailstones get into the egg white. The above-mentioned components are added to the egg white (except for the AdoFlo) and whipped into egg whites for about 30 minutes with a whisk (or a food processor). Leave the egg whites in the container for about 24 hours and cover with cling film. A clear liquid will settle and a contaminated foam will appear which must be skimmed off. The clear liquid is filtered and should mature in the refrigerator for another week. A drop of AdoFlo can be added to avoid possible bubble formation when the paper is coated. And our albumin for coating photo paper is ready.
Advice on coating!
A sufficiently large vessel is filled with albumin for coating. The paper to be coated should float in this for about three minutes. The paper must hang dry so that excess albumin can drain off and existing air bubbles can be removed.