Peter Vlahov
Photography Portfolio
Peter Vlahov
Alternative Photography Recipes
Cyanooil process
My Cyanooil process
This process is based on observed ability of overexopsed Prussian blue pigment to harden gelatin or gum arabic. Oil paint, brushed over a cyanotype print, stays on the parts of the cyanotype, where gelatin was hardened by overexposed Prussian blue, and is then removed in warm water together with the the underlying gelatin/prussian blue unexposed parts of the image.
Try this recipes on your own risk. Mix the ingredients in well ventilated area. Use glowes and protective glasses. Ferric chloride is corrosive. Ammonia is corrosive and have strong, sharp, irritating odor. It can irritate nose, throat, eyes or skin. Potassium ferricyanide can form poisonous gas in strong acids.
Prepare saturated solution by adding chemical in hot water untill no more is dissolved.
Recipe I:
1 tsp gelatin
85 ml boiling water
1 tsp sugar
2 tsp citric acid
5 droppers (about 1.75 ml) ferric chloride (saturated solution)
15 ml ammonia 10% solution in water
8 droppers (about 2.8 ml) potassium ferricyanide (saturated solution)
Optionally, add:
3 drops glycerin
5-10 ml 45% alcohol
Recipe II:
Solution A
200 ml boiling water
1 tsp gelatin
Solution B
2 tsp citric acid
12 droppers (about 4.2 ml) ferric chloride (satu
rated solution)
20 ml ammonia 10% solution in water
Solution C
Potassium ferricyanide (saturated solution)
Mix 50 ml solution A with 30 ml solution B
To every 10 ml of the mixed solutions, add 10 droppers (3.5 ml) of solution C.
Brush 2-3 layers
Exposure under a negative
(I use transparent inkjet film) to sunlight for 10-20 minutes, or about 1-1.30 h. under UV lamp ( I use 100w UV-diodes ptojector)
Overexpose (until the illuminated parts become light and the semi-illuminated parts become dark blue)
Develop in water and dry
After drying – brush oil paint thinned with turpentine over the cyanotype.
Wipe with soft paper.
Develop again with abundant tepid water spraying or in warm water.
Alternatively, exposed, but not yet developed cyanotype can be directly brushed with thinned oil paint and then developed faxt in tepid water.
After drying, remove the Prussian blue pigment in several successive baths of 1 tsp sodium bicarbonate in 1l of water, then in clean water, then in 2 tsp citric acid in 1 l of water, then again clean water. Repeat untill Berlin blue pigment and the yellow stain disappear.