What is cyanotype?
Cyanotype involves combining and coating two chemicals onto a surface (usually paper) to create a photosensitive layer in a pale green colour, which is almost transparent. Once exposed to sunlight then rinsed under water, the chemical reaction turns the mixture into Prussian blue, giving its name to the blueprint process. If the applied solution disappears, the leaves that were blocking the sunlight reveal the original colour of the paper (or whatever was used as a base), whereas the rest of the surface exposed to the sun is now blue.
Get started: prepare the paper
To create some photosensitive paper, you need to apply a coat of special solution. There’s no need to mix chemicals together as this magic potion is readily available to buy online or in craft shops
What you need
- 1 large soft brush
- 1 sheet of thick (watercolour) paper
- 1 kit to create the ferric solution
- 1 non-porous container (any bowl made of glass will do)
- 1 large opaque envelope
- 1 large drawing pad
TIP Before you apply the solution, be careful not to stain yourself. Make sure you protect the surface you are working on, your clothes and your hands.
- Work in a very dark room: the solution you’re going to use can’t be exposed to any UV light at all, otherwise the process won’t work. However, you can use a small LED light to help you see what you’re doing. Pour the solution into a bowl, which should be large enough so that you can easily dip a brush in it.
- Dip the brush lightly into the solution and apply a thin layer, keeping away from the border of the paper so it doesn’t get coloured.
- Ensure the layer is uniform all over, and only cover lightly wherever you think you may have missed a spot. Don’t worry if you’re struggling to see the solution, since it’s hardly visible on the first application.
- Hang the coated paper somewhere hot and dry, and leave it to dry. If possible, do so outside during summer nights, as heat and wind will accelerate the drying process, but it’s also fine to keep it in a very dark room overnight. Be careful not to leave the paper outside until the morning as it must not be exposed to light until you are ready to create your cyanotype.
- Once the paper is fully dried, put it into a big envelope, then put this envelope inside a large drawing pad so it’s completely lightproof. Ideally, use it the next day, although if you store it well away from any light, you can keep it for a few more days.
GOOD TO KNOW Paper composition varies and therefore different types of paper don’t react the same way (when you rinse, you may see some brown staining, the blue dye might wash away, etc). Prior paper tests are essential for best results.
Your first cyanotype
It’s time to work some magic! For your first attempt, it’s best to use a flat plant with just one stem. We recommend ferns as the ideal subject for this
What you need
- Sheets of paper coated with photosensitive solution
- 1 dried fern leaf
- 1 sheet of glass, slightly larger than the paper. Get your sheet of glass cut to size at a DIY store, and cover the sharp edges with duct tape
- 1 washing-up bowl or similar (or a large sink) filled with water
- Prepare everything you need and fill the washing-up bowl or sink with some water. Start to plan out how you are going to arrange your leaf on the sheet of paper.
- Remove a sheet of prepared paper from where you stored it (note the solution may have darkened since) and arrange the leaf as decided. Place the sheet of glass on top and press down firmly.
- Leave everything exposed to sunlight for at least 5 minutes.
- It’s ready when the paper starts to turn a greyish-green colour. Lift the glass sheet and remove the plants. Don’t worry if you can’t see any significant colour changes – this will happen once you rinse the paper.
- Without wasting any time, soak the paper in the water (or under running water). The solution you applied needs to be washed away, and you should notice the water changing colour. Within a few seconds, the blue colour will reveal itself: exposed to the sun, the iron contained in the solution turns into Prussian blue. On the other hand, the leaves that were blocking the sun’s rays appear in the same colour as the base – so in white if the paper was originally white. Congratulations – you’ve just created your first cyanotype!
TIP Make sure the surface you use is completely flat and under the sun. Avoid shadows – including your own!
Edited extract from Cyanotype Workshop by Camille Soularyol & Marie Vendittelli. Official photographer Frédéric Baron-Morin. Published by GMC Publications. Available in bookstores and online at giftstome.co.uk/product/cyanotype-workshop/