Making Cyanotypes
Step to creating a cyanotype:
- Mix the equal parts of Potassium ferricyanide and Ferric ammonium citrate.
- Paint one or two layers of the solution on a surface (probably paper).
- Let the paper dry in a dark room. The mixed chemicals react to UV light, so most indoor light sources will not affect the paper too much.
- Create a negative that will be contact-printed (not using an enlarger). The negative should be lower contrast that expected.
- Place the negative, ink side down, on top of the coated paper. Sandwich the two together between glass or in some type of contact-printing frame.
- Expose the paper and negative to UV light. Either place the printing frame in direct sun, or use a UV light box.
- After the exposed chemical has cured (about 8 minutes in the light box - more in the sun), wash the uncured chemical off of the paper with water.
- To speed up the oxidation process and get a rich, deep blue color immediately, rinse the paper with a diluted hydrogen peroxide solution.
- Wash again, and allow the paper to dry.
Here are my 8 negatives for the book. They were digital images that I cropped, reversed, and inverted. Then I applied a specific correction curve (tonal) so that the contrast would be appropriate for the cyanotype process. The material is a plastic transparency-type of material with a thin ceramic coating. The coating allows it to hold an ink jet print. Each negative is 7"x10.5".
The main experimenting I did as I learned this process had to do with different types of paper. My first two prints (below) are on the Japanese paper that I used for the book. The second print below was also my test piece for experimenting with line work and numbers over the image. There are two differences between the cyanotype quality of these two prints: for the first print, the negative was placed with the ink side away from the paper. This created a much less clear image. Also the first print was over-wahsed (or not carefully washed) and many of the paper fibers floated away from the paper, which also decreased image quality.
My next step was to print the eight images for the book. I had learned from the two first prints that I did need to reverse the image, and the correction curve was needed for better contrast. I also learned how to wash this delicate Japanese paper in a less aggressive manner.
Since I would be further altering the images for the book, I wanted to create a few "good prints" of just the cyanotype images. I switched to a specialty paper which was coated to receive a photosensitive chemical application. I double coated each piece, and I first printed an exposure test print to judge the exposure length. On the Japanese paper I used an 8 minute exposure. This specialty paper I tested at 5, 8, and 10 minutes, and the 10 minute exposure appeared to yield the best results. I made three prints of the same image and discovered that there were other factors involved in getting a good print. The chemical application needed to be smooth and even, and on many of my papers, it was not even. The heavy sizing of the paper made it difficult to not get too much chemical on the surface of the paper. Also, even though this paper was much stronger than the Japanese paper, running it underwater was still damaging the surface fibers too much. Submerging in a tray of water worked better.
Since I would be further altering the images for the book, I wanted to create a few "good prints" of just the cyanotype images. I switched to a specialty paper which was coated to receive a photosensitive chemical application. I double coated each piece, and I first printed an exposure test print to judge the exposure length. On the Japanese paper I used an 8 minute exposure. This specialty paper I tested at 5, 8, and 10 minutes, and the 10 minute exposure appeared to yield the best results. I made three prints of the same image and discovered that there were other factors involved in getting a good print. The chemical application needed to be smooth and even, and on many of my papers, it was not even. The heavy sizing of the paper made it difficult to not get too much chemical on the surface of the paper. Also, even though this paper was much stronger than the Japanese paper, running it underwater was still damaging the surface fibers too much. Submerging in a tray of water worked better.
I coated one larger sheet of this specialty paper so that a border of uncoated (i.e. white) paper would surround the image. I had hoped to get one very good print out of this process, but the problems with chemical application are evident on this piece (in the light-toned horizontal banding across the image).
I also decided to experiment with another type of paper. These smaller sheets are just high quality, heavy-weight, cold-press watercolor paper. I coated four sheets. These are my most successful of the individual prints. The paper, though, did not need as long of an exposure time, and the first of these four is a little dark. After the second and third turned out better, I decided to reprint the first image, but my fourth piece of paper had coating issues and the light-toned horizontal bands appeared again. In the future, I will use this type of paper more.