I wanted to compare new cyanotype with the blue flash formula on a fair comparison so I did several tests using Hahnemühle Platinum Rag paper. All tests were done on a 4x5 enlarger using a 100 watt 380 nm UV led and a 4x5 Ortho Litho negative. The new cyanotype formula took anywhere from 30 to 45 minutes and the blue flash formula took from 9 to 15 minutes. The first discovery was the new cyanotype formula is way to low contrast for me anyway and did not accurately represent the negative, this could be fixed on a digital negative with a curve applied but my goal was minimal fussing around especially for beginners, the blue flash formula preformed well and almost exactly matched the tonality of a silver gelatin print. The second discovery was with any formula I used using the Ferric Ammonium Oxalate in it there was a very noticeable brown / yellow stain in the highlights, after some research I found out that a simple 1 to 2 % or 4 to 5 PH citric acid bath fixed the problem, you simply develop the image in this bath and place it in 2 or more baths of citric acid before rinsing in plain water to remove the stain. The most impressive thing I discovered about the blue flash formula is it is perfectly suitable for almost any paper, for example new cyanotype on Canson XL turns blue and unusable in an hour but blue flash works just fine, it also worked amazingly on Masters Touch hot press acid free 20% cotton watercolor paper and in fact it looked the best of any of the prints. And finally the new cyanotype and blue flash are perfectly suitable for toning however they are not at all suitable for due tone or tri color cyanotypes as they discolor badly with multiple layers, I also found it is best to use ammonia to bleach cyanotypes made with Ferric Ammonium Oxalate.
