Jalo Porkkala has tested eleven different watercolor and etching papers for cyanotypes and shares the result for cyanotype printing.
We took eleven different watercolor and etching papers that we were able to find in our school’s paper stock – the school is the Satakunta University of Applied Sciences / Department of Fine Art in Kankaanpää, Finland and testing them for printing cyanotypes. We made a few exposure tests using the traditional cyanotype process (blueprint), with a view to finding a standard exposure to produce the maximum “black” for each paper. At the same time we examined the suitability of these papers for printing cyanotype and compared the blue tones the papers could produce.
The classic cyanotype is known to work almost on any paper, and mixing of the sensitizer is simple enough: you only need two chemicals to make two separate stock solutions. This time we didn’t mix them by ourselves but used ready-made solutions by Hopeavedos, a Finnish supplier. We coated the papers with a mixture of the two solutions (see the classic cyanotype formula). None of the papers were given extra sizing.
As we expected, there were no great differences in tone or sensitivity between the sensitized papers. The exposure times to produce maximum tone density varied from 6 to 10 minutes when exposed with our UV-exposure unit from one-meter distance. All samples were exposed in a vacuum frame, partly covering the sensitized areas with blank Agfa CopyJet transparency, hoping to find out something about its UV-transmittance properties.
Below are the results of our little paper survey – we scanned pieces of each paper showing maximum cyano density plus the uncoated paper base (samples shown approximately life-size). In conclusion, our experience is that all of these tested papers could be used successfully in traditional cyanotype printing. However, there are a few papers that print better than the others.