Measuring Cyanotype Chemicals Without a Scale – including Cheat Sheet

A practical guide to measuring cyanotype chemicals with teaspoons and tablespoons. Many cyanotype practitioners (I am one example) like to work with precise measurements and repeatable results using a gram scale, but beginners may not yet have invested in a gram scale. Fortunately, there is another option using spoons. I measured common kitchen measuring spoons filled with cyanotype chemicals 20 times each and calculated the averages. The results provide a simple way to prepare solutions and working baths using teaspoons and tablespoons instead of a scale.

Writer / Malin Fabbri

When using any chemicals, read the MSDS (Material Safety Data Sheet) before attempting to use them and use the correct safety equipment. 

Making cyanotypes using negatives, I like to be exact with my measurements and get repeatable results. I understand that not everyone works that way, and I am often asked by beginners who have not yet invested in equipment or a scale how they can measure cyanotype chemicals accurately enough for practical use.

To answer this question, I measured 1 tablespoon and 1 teaspoon of fresh Ferric Ammonium Citrate 20 times, and worked out the average. I did the same with Potassium Ferricyanide, and while I was at it, I also measured Citric Acid, which can be used for acid washing cyanotypes, and Calcium Carbonate, which is often used in cyanotype toning.

For acid washing, see the article Vinegar Developed Cyanotypes – Non-Toxic Midtone Contrast Control. The article uses vinegar, but I find citric acid easier because vinegar is sold in many different strengths.

For toning, Calcium Carbonate is used in several recipes, including Annette Golaz’s sweet potato peel toner (scroll down to the bottom).

Instead of keeping these notes pinned to the wall in my studio, I thought I would do what I usually do and share the information freely, no strings attached, with anyone who may find it useful. If you appreciate receiving free information like this, please consider becoming a supporting member to help us continue publishing articles and resources. Members can also download the Printable Cheat Sheet: Cyanotype Recipes Without a Scale for free. The Cheat Sheet is available for purchase for non-members.

Practical use of measured cyanotype chemicals

First, get a set of measuring spoons, like the ones used for baking. After using them with photographic chemicals, do not return them to the kitchen. Keep a separate set for photographic use. 

Cyanotype Solution A

• To prepare a 25% Ferric Ammonium Citrate solution (the most common recipe), use 3.5 tablespoons of Ferric Ammonium Citrate and add water until the final volume reaches 100 mL.
• To prepare a 10% Ferric Ammonium Citrate solution, use 1.4 tablespoons, stir, and top up with water until the final volume reaches 100 mL.

Cyanotype Solution B

• To prepare a 10% Potassium Ferricyanide solution, use 2.1 teaspoons of Potassium Ferricyanide and add water until the final volume reaches 100 mL.

To make the cyanotype solution, you then take equal parts of Solution A and Solution B and mix them. For more information on how to make cyanotypes, see the article here.

Citric Acid

If you are preparing an acid wash for cyanotypes:

• 4 g = slightly more than 1 teaspoon (1 teaspoon averages 3.9 g)
• 6 g = approximately 1.5 teaspoons
• 8 g = 2.2 teaspoons + 2000 mL water (this is the recipe I tend to use)
• 12 g = approximately 1 tablespoon (1 tablespoon averages 12.65 g)

Calcium Carbonate

For Calcium Carbonate, use a spice measure, the small 1 mL measure often included in measuring spoon sets.

• 0.5 g = slightly less than 1 spice measure (1 spice measure averages 0.7 g)
• 1 g = slightly less than 2 spice measures (1.4 mL) + 2000 mL water (this is the recipe I tend to use.

All the conversions can be seen here:

Keep in mind that these measurements were made in my studio. If you live in an extremely humid or very dry environment, the results may vary slightly. Good luck cyanotyping!

Malin Fabbri is the editor and founder of AlternativePhotography.com, author of several books on alternative photographic processes, and experiments with a variety of techniques, including anthotypes, cyanotypes, photopolymer gravure, chlorophyll prints, lumens, cyanograms, photosynthesis, pinholes, and solargraphs.