Re: New Cyanotype

On Tue, 18 May 2004, Christina Z. Anderson wrote:
> The complaints about the traditional (old) process are that it is rather
> slow, the ammonium iron citrate grows mold easily, the sensitizer does not
> often absorb into paper well, the Prussian blue is soluble and washes out
> during wet processing, and stained highlights are quite common because
> excess ferrous iron in heavily exposed areas diffuses out into the
> highlights.

Christina, I notice that you say "the complaints about the traditional
(old) process are....", but you don't say you have observed these things
yourself. I have made hundreds of cyanotypes, and taught airhead
undergraduates who must in the aggregate have made thousands more-- and
NEVER seen the Prussian blue wash out during wet processing except in two
circumstances:

1. When the emulsion is too fresh.. I don't mean A&B freshly mixed
together, but when the A & the B themselves have not aged enough. I found
that two hours old they washed off about 60%, after that they washed off
successively less. Until about day 3, or maybe 4, no washing off. That
is, no "blue water." However, the top visible step of a freshly exposed
but not yet developed print does drop down 2, or 3, or more steps in
development. I don't know if New Cyanotype does that, but you can easily
allow for it in exposure. (And that makes green not blue water.)

2. When the paper is not absorbent enough or too much emulsion is sloshed
on. Look at the freshly coated paper at an angle -- if you see puddling,
it will wash off after exposure, often leaving white spots.

Perhaps alkaline wash water has this effect, but I do not believe it is
intrinsic to the medium. I have also NOT seen those "stained highlights."
except where the negative was too thin.

Judy
Received on Tue May 18 23:47:08 2004