What is cyanotype? Explanation, operation and correct spelling

Cyanotype is a photographic printing process in which UV light changes a light-sensitive iron solution into Prussian blue. You place an object or negative directly on coated paper or textile, expose it and rinse the unexposed parts with water. The result is a deep blue print with light shapes. “Sianotype” and “cianotype” are common phonetic spellings, but cyanotype is the official international name.

How does cyanotype work?

The classical method uses ferric ammonium citrate and potassium ferricyanide. These are stored as two separate stock solutions and only mixed immediately before use. After coating, the material dries in the dark. UV light then changes the iron compound in the exposed parts. During rinsing, the characteristic Prussian blue is created and stabilized in the fibers.

If you want to try it right away, follow the complete beginners guide or check out the cyanotype kits and materials .

Is a cyanotype the same as a blueprint?

The words overlap, but are not always used exactly the same. The cyanotype process was used in the nineteenth century to reproduce drawings and plans cheaply; that is where the common word “blueprint” comes from. Nowadays, by cyanotype, artists mainly mean photographic contact prints and photograms, while “blueprint” can also figuratively mean a plan or design.

Cyanotype, sianotype or cianotype?

In Dutch the beginning of cyanotype sounds something like “sia”. As a result, people often search for sianotype, cianotype, cyanoprint or ciano print. They usually mean the same process. For titles, product information and professional literature, cyanotype is the correct spelling. In a practical explanation it may be useful to mention the variants once, but repetition of all spellings makes text less pleasant to read.

What is a cyanoprint?

Cyanoprint is an understandable informal name for the end result. It can be a botanical photogram, a print from a digital negative, a textile print or an experimental work. The process is called cyanotype; the print is called cyanotype or cyanoprint.

What can you print?

• Plants and feathers: simple photograms with clear silhouettes.
• Transparent materials: for layered blue and light tones.
• Digital Negatives: for photographs, illustrations and fine detail.
• Textiles: mainly cotton, linen, silk and other natural fibers.
• Wood or paper objects: provided the surface is sufficiently absorbent.

Also check out 10 cyanotype ideas for feasible projects.

Why does cyanotype turn blue?

After UV exposure and rinsing, an insoluble iron pigment known as Prussian blue forms. Unexposed, soluble components wash away. As a result, the covered parts remain light and the exposed parts turn blue. The color often deepens during drying and oxidation.

Is cyanotype difficult?

The basic process is forgiving, but a repeatable print requires control over five things: paper or textile, coating, drying, contact and UV dose. Most beginner problems can therefore be easily diagnosed. A test strip and clear notes provide faster improvement than repeating a complete print.

Frequently asked questions

Do you need a darkroom?

No. Coating and drying can be done in subdued artificial light. Avoid direct sunlight and strong UV sources until the print is ready for exposure.

Can you make cyanotype with a regular photo?

Yes, if you first convert the photo into a transparent negative. Because cyanotype is a contact process, the negative must have the same dimensions as the desired print.

Is cyanotype only for paper?

No. Natural, absorbent materials often work too. Additional rules for pre-washing and maintenance apply to clothing and accessories; see cyanotype on textile .

Why do I see different shades of blue?

Lighting, coating, paper, rinsing and oxidation affect the color. Use the troubleshooter when the contrast or blue is disappointing.