Re: Blue-Black Cyanotype & Luster

Hi Mark,

for dark blue-blacks I´d propose that you bleach the cyanotype in an alkaline solution till the midtones are nearly yellow-brown. Then rinse in tap water and wash the print in 0,3 % acetic acid for at least 5 minutes. My test have shown that this step will regain prussian blue that has not been terminally converted into ferric hydroxide and is important to neutralise the alkali (otherwise it is very likely that the paper will stain heavily when toned). Tone in tannic (1%) or gallic (0,5%) acid solution and finally wash in tap water.

I´ve uploaded samples as http://fb42.s6.domainkunden.de/kunden/hamann/toning_examples.JPG. The first line of the prints in both drawers was done like described (in the left drawer with tannic acid, in the right with gallic acid) with stronger bleaching from left to right.

All the best
  Kai Hamann
Received on Tue Oct 4 11:38:41 2005