Digital BW, The Print

Ferrocyanide was a commonly used by press photographers in the thirties. 

All prints that been exposed to ferrocyanide are eventually destroyed
by it, no matter how much "archival" washing. Of course, if you try
the recommended hours-long washing you're a villain, into wasting water. 

Since it's terribly poisonous and there's no way to neutralize it on a
print or in the sewer, one must ignore both permanence and the
environment to use it. 

In post-printing it can produce brilliant, localized whites in a print
that's otherwise dark and moody. But Photoshop is a more honorable tool. 



> 
> If anyone has ever tried this technique, it is quite marvellous, but
> extremely, 
> extremely reactive.  Practice. practice, and practice again, using
lots of
> H2O 
> from the end of a small nozzle hose allowing for a focused pour of
H2O on
> the subject area, and the use of a fine, fine brush, is essential. :)
> 
> Bruce introduced me to this technique, more the 20 years ago, and I have
> not for gotten the moment I called him ³Captain Ferricyanide,² during a