Cyanotypes, My Blue Mistress. by Ron Cowie

Cyanotypes Shouldn't Be Ignored

The cyanotype is one of the oldest photo processes. It is also the most humble and under appreciated. How can a process that only has two ingredients, develops in water, and lasts forever be so maligned?

I’ll tell you why. It is because the cyanotype was never intended for that fancy, uptown photo stuff. The cyanotype was “invented” so a guy could copy is lab notes on the cheap. 

From its humble start, great things have been made with this process. It is worth starting our journey here for a variety of reasons.

Cyanotypes are inexpensive to make.

Why spend all your hard earned cash on chemicals when you don’t have to? For less than fifty dollars you can make a gallon of sensitizer. Consider the amount of sensitizer it takes to make one print (about 2ml) you’re looking at a lot of soup to play with. 

Cyanotypes are simple but offer a great deal of variation. 

You can adjust the intensity and contrast of the tones through adjusting the Ph of the water. Vinegar or citric acid is the simplest solution (in every sense of the word). 

Cyanotype Recipe

What you need

  1. Ferric Ammonium Citrate
  2. Potassium Ferricyanide
  3. distilled water
  4. brown bottles. with eye droppers


Solution A

  • 25 grams Ferric Ammonium Citrate (green crystals)
  • 100 ml distilled water

Solution B

  • 15 Grams Potassium Ferricyanide
  • 100ml distilled water

Mix equal parts of each solution into a small cup (plastic or glass is ideal). Swirl around the solution to make sure they are mixed. Pour onto your paper and with a glass rod or damp brush move the solution around to cover the desired area. 

At this point it is important to let the paper absorb the light sensitive solution. This means letting the solution sit in a dimly lit space. While the cyanotype process is only sensitive to ultra-violet light, exposure is cumulative so it makes sense to reduce the amount of light that hits the paper whenever possible. Just walk away.

While it is not necessary, I have found the addition of a solution called “tween” to be helpful in providing an even absorption. What tween does is break down the surface tension of the solution so it is absorbed evenly.

Once the coated paper has an even matte surface (careful not to touch because it is still wet) take a blow drier and put it on the warm setting. Dry the paper completely. 


The fun part about cyanotypes is the simplicity of printing. This is an inspection process which means you check your print as you go. This is done by using a contact printing frame with a split back. This allows you to open up the back, peel the paper away from the negative and check how the exposure is going. 

When the print looks like you want it to look, it needs to be exposed for a longer time. The ideal finished exposure should have all the shadows blocked up and the highlights about 2 times darker than desired. 

The reason for this is during the development process, the exposed material on the paper surface washes away. I layman's terms, the print lightens up.

Full development has occurred when the yellow-green stain has been washed out of the highlights or unexposed parts of your print. 

Toning Cyanotypes.

Most materials you need to tone a cyanotype can be found in the baking or laundry aisle of your grocery store. These are just a few of the items you can use to alter the color and contrast of your cyanotypes. There are two phases of toning: bleaching and toning. The bleach phase comes first.  

  • Borax (For bleaching)
  • Sodium Carbonate (Bleaching)
  • Tea (Red Rose or Lipton) for toning
  • Tannic Acid (toning)
  • Wine Tannin (toning)
  • Citric Acid (Changes color to teal)

This is not a comprehensive list. Here are some links that discuss cyanotype toning in greater detail.

Listen to my colleague Jeff Curto's Podcasts