A simple guide to the art of cyanotype.
Traditional cyanotype is a camera-less photographic process that produces beautiful Prussian blue prints. This process was discovered by Sir John Hercshel in 1842, and was used as a means of reproducing drawing s and diagrams (blueprints).
In the mid-nineteenth century, artist and botanist, Anna Atkins brought the process to the attention and imagination of the public when she produced a series of cyanotype prints of seaweeds. She placed the algae specimens directly on to photosensitised paper creating a silhouette effect, known as a photogram.
The process involves mixing two chemicals: potassium ferricyanide and ammonium citrate to create a photosensitive solution. This is then applied straight after mixing to an absorbent surface (paper, fabric, bone, leather, shell, etc.) after which it is left in a dark place to dry. Allowing light to reach the paper during the drying process will spoil the print. The paper (or substrate) can then be stored in a lightproof container or bag before use.
Prints can then be made by placing a negative (object or a photographic negative) on to the surface and exposing the coated surface to sunlight or an ultraviolet lamp. Results ae usually obtained after about 10-20 mins, though this can vary considerably due to the strength of the sun and the surface being used to create the print. It’s best to create a test piece prior to exposure to ensure you get the results you want.
Prints are then developed by running under cold water. This process takes around 5 minutes, but again can vary. A dilute solution of hydrogen peroxide can be used to accelerate the process. The chemistry of tap water can impact on the end result, and it is possible to bleach prints using a solution of soium carbonate (washing soda) if required.
The wet process is a variation on the traditional cyanotype method which has captured the imagination of many artists working in cyanotype. You can create wet cyanotype on dry pre-prepared sheets of photosensitised paper (or chosen substrate) or directly into the wet chemicals as they are applied to you chosen paper (wet into wet). Introducing wet elements to the print as it develops corrupts the process leaving interesting marks and colourations. Working in this way it is important to be aware of the toxicity of the chemical reactions and to allow plenty of ventilation and to wear protective clothing when handling chemicals.
Coating the paper
For classic cyanotype, mix solutions of ammonium ferric citrate and potassium ferricyanide (diluted as per manufacturers instructions) in equal parts. Lay your paper on a board or glass and apply the solution with a foam or hake brush, avoid brushes with metal ferrules, as these can react with the cyanotype chemicals. You can apply the solution in a uniform or more artistic manner. If you are using pre-prepared paper spritz with water to wet the surface.
Applying your negative
Create your composition by laying your subject on the wet paper. Cyanotype is a contact printing process, where you cover the paper will not expose and the areas exposed to the sun will colour, although with the wet process leaks and chemical reactions take place and fresh botanicals may also leave colour and add moisture.
Adding soap and other ingredients
I like to liberally apply soap suds to a lot of my wet cyanotypes once I am happy with my composition. At this point you can also add sea salt, turmeric, paprika, coffee grounds, and spritz with diluted vinegar. Then cover with glass and clamp to hold in place.
Wet cyanotypes can be left in the sun for a few hours to develop or for days or weeks. During developing you may see the print turn blue, then the colour all but disappear only to come back with strong rust and grey tones.
Washing the print
Wash your print with tap water until the water runs clear and all traces of yellow have gone from unexposed parts of the paper. In a tray agitate for 2-3 mins changing water as needed and then leave to soak for a couple more minutes agitating occasionally. Peg up or lay flat to dry.
The print can take several days to fully develop however a final wash in diluted hydrogen peroxide will oxidise the print and reveal its final colour. You may wish to photograph the print before this takes place if you intend to use it as part of a digital composition.
A few things I have learned along the way that may be of help. Wet cyanotype is unpredictable and results are serendipitous, but there are a few thigs you can do to try and control the end result of this process. This list is by no means exhaustive but I hope might be helpful to anyone just starting out. The process is all about breaking rules so the best thing to do is to embrace you inner child, play and explore.
For best results and prints that will be archival you will want to use paper that is free from alkaline buffering. Papers with low pH can yield a green tone in the finished print and those with a high pH can give a grey tone to your finished print. I prefer to use a smooth surface and work primarily with hot pressed papers such as Bristol board and HahnemÜhle platinum rag, which both give a strong bright white to the final print. A cold pressed paper will be rougher in texture. The paper needs to survive the washing process, so although any can be used, it’s a good idea to start with heavier weighted papers.
I first got into cyanotype a few years ago as a way of creating prints of my photography at home, and digital negatives can be made by turning images black and white, applying strong contrast and inverting within photo editing software such as Adobe Photoshop. These can be applied to wet paper to which soap, spices and other ingredients have been introduced, and also combined with botanicals, lace or any other negative, to build composite images directly on the paper.
I like to add gold leaf to some of my wet cyanotypes, accenting parts of the print (or even hiding un-appealing bits!) it is easily applied using a size and burnishing brush, or painting accents using an 18ct gold pen. There is no need to go to the expense of using real gold leaf as cheaper alternatives are available and look good.
Prints can be hand coloured with watercolour, inks, watercolour pencils and oils. If you punch holes in your prints you can embroider them and cutting them up to create collages is another way to get creative with prints that may have not gone to plan.
I have created a series of wet cyanotypes in broken eggshells which I then gilded with gold leaf. Botanicals can be applied to the wet solution in the eggshells and left out in a sheltered place to develop in an eggbox. Care needs to be taken to remove the membrane prior to coating in solution.
Fabric is another medium which lends itself to wet cyanotype and natural materials like cotton, hemp and calico are good to use, following the same process as with a paper print. The washing process is much easier than with paper too.
Most natural materials can be used as a surface and I have applied wet cyanotype to wood, found bones and skulls and old leather.
It is possible to achieve a multiple exposure effect by moving the negative / subject during the exposure time. You can also add more cyanotype solution to areas of your print to increase the tonal range in the finished print. You can also coat and expose then recoat and expose the print, creating distinct areas of different texture and colour.
A wash in alkali solutions (pH > 7) of ammonia, sodium bicarbonate and borax will all lighten a print. A wash in a bath of acidic solutions (pH<7) such as tannic acid, gallic acid or strong tea or coffee will darken the print. Should you wish to keep the tonal range similar to your cyanotype you can bleach the finished print and rinse prior to washing your print in a toning solution. As it can take several for the full oxidisation to take place it may be a good idea to wash in diluted hydrogen peroxide prior to a toning. The pH of the water where you live can also affect the colours of your final print.
The environment & plastics
I would urge you to think twice before using cling film, it does make interesting patterns, but it is a single use product and can end up becoming pollution. Re-purposing old picture frames is a good way to create frames for exposing prints in which can be re-used.
Health and safety
It is important to follow safety precautions when mixing and applying wet chemicals. Gloves, eye protection and a mask should be worn where there are risks of spills and inhalation. Do also be aware that cyanotype chemicals stain, so unless you also want to get creative with your wardrobe, wear an apron to protect clothing, and be aware of the environment you are working in.
For more information about how I go about creating my wet cyanotypes, please read my blog post “Camerless creativity” HERE.
Many of my cyantype images are available as greetings cards. If you would like to buy one it really helps support my work. I am also able to arrange bespoke cyanotype workshops to all ages and abilities, I have worked in education and have a current enhanced DBS registered on the update service. Thank you.