Cyantype

You've probably already heard about a #blueprint, or maybe even saw one. Those are stereotypically for construction plans of buildings or machines. But have you ever wondered why they are actually blue and not – for example – black?
This color comes actually from the printing method #Cyanotype: It was developed in 1842
by John Herschel, and was used over decades to copy or duplicate documents – in a time before we had modern printers and copy machines.
For this #printing method, you first have to mix ferric ammonium citrate with potassium ferricyanide in a ratio of 25:10 in order to get a UV-sensitive green/yellow-ish (pic 1) mixture. After applying it to a medium like paper or cloth, you can use already prepared negatives, stencils or other materials (2) to design your layout. Then you have to expose it to UV light. You could do it with regular sunlight, but you have more control of the result by using a UV lamp (3). After about 10 minutes (depending on your settings or the UV index) you can wash your print in a water tank (5) to remove the green and yellow colors and you will have a #cyan-colored (7) end result which you can then enjoy in a hostel in Tallinn, Estonia (8) – but this step is optional.
You can even manipulate the final color by using a second water tank with other chemicals like hydrogen peroxide – coffee, red wine or Coke works as well (with different results).
Today, cyanotype is only used for artistic purposes and there are cheaper, faster and more accurate methods to multiply documents. But the interest is still there:
In May 2022 I was invited by Prof. Holger Jacobs to give an intense workshop over a week at the University of Applied Arts Düsseldorf to teach art students how to use this method in combination with typography. I will publish another post about this workshop and the final exhibition very soon!

*The yellow photo of the UV lamp is edited to make it easier to look at; in the very last photo, I increased the contrast by a lot. Though I should be transparent about this :) The blue end result (6, 7) on the other hand is not edited – this is how intense the blue actually is.