RE: Colour of Van Dyke Prints...

From: Loris Medici ^lt;>
Date: 11/14/04-09:41:05 AM Z
Message-id: <000f01c4ca60$5aed0350$ce02500a@altinyildiz.boyner>

Christina, the suggestion made by Sandy below is very important! After
reading Sandy's Kallitype article, I immediately included a citric acid
bath before washing. The results were spectacular indeed: very clean
whites and absolutely no staining.

-----Original Message-----
From: Sandy King []
Sent: Sunday, November 14, 2004 5:24 PM
Subject: RE: Colour of Van Dyke Prints...

Example 2 -- Most sources recommend a first wash/developing in a
running water-bath for 1-2 minutes. This is fine if the water is base or
slightly acidic, but disastrous if the water is alkaline because in that
case the residual ferric salts that were left in the print after
development reactions will be changed to iron hydroxide, causing
staining that is virtually impossible to remove. Instead of the running
water bath I recommend soaking the print for 2-3 minutes in a bath of
water that has been made acidic by the addition of about 1/2 teaspoonful
of citric acid per liter water. This will clear virtually all of the
ferric salts. Follow this with a 1-2 minute running bath.
Received on Sun Nov 14 09:41:25 2004

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