From: Liam Lawless (liam.lawless@blueyonder.co.uk)
Date: 10/12/02-10:30:44 AM Z
Richard,
Two things to look at. If you're getting a blue solution, it's probably the
condition of the chemicals, or contamination of mixing vessel. With poor
storage, ferric amm. citrate may start to become ferrous, or pot.
ferricyanide may start to turn to pot. ferrocyanide, and either change will
result in formation of Prussian blue on mixing, without UV exposure.
But your paper just might be unsuitable. Once I coated some scraps of paper
for tests, using an Arista APH film box for support. Instant deep blue
colour where I got some sensitiser on the box. Probably the box was acidic.
Just did a test - added a dash of tartaric acid solution to freshly mixed
cyanotype goo - it turned blue. Doubt if anyone makes acid art papers, but
could be a drop of acid has got into the system somewhere.
Liam
-----Original Message-----
From: Richard Urmonas [mailto:rurmonas@senet.com.au]
Sent: 12 October 2002 12:25
To: alt-photo-process-l@usask.ca
Subject: Problem with cyanotype
I am trying cyanotype, but I am having a problem with
the solutions going blue when mixed. I am using
Solution A: Ferric Ammonium Citrate Green 12.5g
Water to make 50 ml
Solution B: Potassium Ferricyanide 4.8g
Water to make 50 ml
When I coat the paper I found I was getting substantial blue staining.
In a series of tests I ended up working under red safelight.
I placed a drop of the citrate solution on the paper and
spread it out with another piece of paper. I then placed
a drop of ferricyanide solution on the paper. I could see the
drop darken almost instantly.
Does anyone know what is going wrong??
Richard
--- Richard Urmonas rurmonas@senet.com.au
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