This post was originally posted to my tumblr in 2017, this version has been slightly revised.
While trying to improve the quality of the cyanotype prints made on my home built enlarger I came across a whole number of different techniques for increasing the sensitivity and quality of cyanotype prints, but I’ve never done a comprehensive comparison.
So a few days ago I sat down and tested 6 different cyanotype formulas and techniques. All prints were made on A5 size printer paper and were exposed for 15 minutes. I chose a negative that has a wide dynamic range with deep shadows and some very bright highlights. All images were first washed in tap water and then in a weak solution of acetic acid and hydrogen peroxide.
I also tested toning with three of the techniques using a mix of tannic acid and black tea.
Most of the different formulations used here were taken from Mike Ware’s excellent Cyanomicon which can be found here: http://www.mikeware.co.uk/mikeware/downloads.html