Small historical nod
The antique printing technique Van Dyke (also called brown printing) comes from the Callitipia which is a technique developed in 1889 by Arndt e Troost.
It is named after Anton Van Dyke, a Flemish painter famous for the beauty of his brown tones.
This process is a hybrid between cyanotype and classic silver salt print.
Having been born about ten years after the platinotype, it has never been a particularly popular process even if it allows to obtain excellent prints if well executed.
Like all the ancient printing techniques of that period, also this one is made by contact so you need a negative of the same size as the final print..
Chemistry used and recipe
The chemistry, as previously mentioned, is a hybrid between the cyanotype and the printing with argetic salts.
Here is the basic recipe:
The emulsion is prepared with three different solutions:
Solution A: 9g of Ammonium Iron Citrate dissolved in 33ml of distilled water.
Solution B: 1.5g of Tartaric Acid dissolved in 33ml of distilled water
Solution C: 3.8g of Silver Nitrate dissolved in 33ml of distilled water
Solutions A and B are combined with dimmed light and then C is added to the result. Mix everything well and leave it to rest for 24/48 hours before the first use.
The emulsion can be used for several months if stored in a cool, dark place.
After exposure, the print must be washed in a bath of water and 3% citric acid for 3 minutes.
The second bath should be done in 2% Sodium Thiosulfate for 2/3 minutes.
Finally, the print should be washed for a long time in running water (at least 30 minutes).
I usually use the Bergger COT 320 but also the Arches Platine or the 45g Washi are fine.
Van Dyke Brown Print Workshop
If you are interested in a workshop on this magical ancient technique, check the available dates in the near future in Italy or contact me directly if you want to organize a One to One workshop.