Quote Originally Posted by Donald Qualls
I used my existing cyanotype A solution, 200 g/L green ferric ammonium citrate in distilled water; the bottle was mixed around 18 months ago, and has been opened and small amounts used a number of times (in case that makes a difference). For each print, I coated 1 ml of this solution onto a 4 1/2 x 6 inch piece of Montval "Brut" (rough) watercolor paper. Prints were coated with a foam brush and dried under red safelight, some with a hair drier and others allowed to dry naturally.
Thanks for posting your experiment. I think that the alternative print community benefits from a free and open exchange of methods and experiments. Plus it keeps us from all repeating the same mistakes .

The increase in speed might be more significant if the oxalate salt of iron was used, but I have no data on this. Only a suggestion.

I think that the traditional method for cyanotypes shows an advantage when it comes to development. The two solutions are on the paper. With brushing on the ferricyanide, you open the possibility of uneven development. Perhaps if you had a super saturated solution of potassium ferricyanide that you developed your print in? That might take care of washing away the ferric ammonium citrate to early. Just a suggestion.