A how to guide
What you need:
- Heavy, absorbent paper like watercolour paper, or a canvas.
- Photosensitive solution (described below).
- A paintbrush.
- Some objects like feathers, leaves, bits of metal, paper shapes, etc.
- Photo negatives printed on overhead projector film (optional).
- A sunny window or space outdoors.
- A sink and running water.
STEP 1: The Photosensitive Solution
The chemicals used to make the solution are easily available online. You can purchase pre-mixed solution, which is the easiest way when beginning to make cyanotypes, or you can buy the different chemical powders separately and mix them yourself.
For pre-mixed solution one U.K. supplier is: http://cyanotype.co.uk/cyanotype1.html
If buying the powders you will need to purchase: Ferric Ammonium Citrate (FAC) and Potassium Ferricyanide (PF).
A supplier can be found by following these links: http://www.wetplatesupplies.com/alternative-processes/cyanotype/potassium-ferricyanide.html http://www.wetplatesupplies.com/alternative-processes/cyanotype/ammonium-ferric-citrate-green.html
Remember to read and follow all the safety information associated with these chemicals. Once you have purchased your chemicals you will need to follow the following recipe to make your solution:
In one bottle, combine 25g of Ferric Ammonium Citrate with 100mL of water (preferably demineralised, and never hard water). In another bottle, combine 10g of Potassium Ferricyanide in 100mL of water. Close the bottles tightly and give a gentle shake to dissolve the powders. These can be store somewhere dark indefinitely, as long as the two solutions are not mixed. Once mixed together, they cannot be stored, and any unused mixture must be disposed of, along with their container, in a bin.
To make the photosensitive solution, mix an equal amount from the FAC bottle and from the PF bottle. In order to create two A4 size photo prints, for example, mix 1 tsp of FAC solution with 1 tsp of PF solution.
Note: This should be done after the sun goes down, in order for it not to react with UV light!
STEP 2: Preparing the paper
STEP 3: Setting up the print
STEP 4: Creating the print
STEP 5: Rinsing
Some problems you might have:
The image gets washed away in the final step: This is normally caused when the image has not been allowed to develop fully. Next time you try, allow the paper to sit in your window for a little while longer or wait for a sunnier day. You may need to test different times in order to get just the right amount of colour for what you want to achieve. Sometimes a light, ghostly image can be just as nice as a deep bold one!
The image is blurry: The objects or negatives need to sit flush on the paper, or else some light may be allowed underneath. This will cause a blurring effect. If it’s a windy day, you may want to place a pane of glass over your photo to keep everything in place.
Parts of your picture turn yellow or brown: The blue pigment left behind by the process will react with some of the ingredients in certain soaps. Make sure you rinse the image in water only, and if you hang it up on the clothesline to dry, make sure it’s with clean pegs.