Re: Double Coating of Platine

William Laven (wmlaven@platinotype.com)
Fri, 27 Feb 1998 11:36:05 -0800 (PST)

>What is the procedure for double coating Platine Paper for Pt/Pd printing?.
>I have understood that the second coat could be diluted with distilled
>water. How much drying is needed between the first and second coats? What
>are the advantages of double coating. What are the effects on a step wedge
>contact printed between one and two coats? it obviously expensive doing two
>coats on large format. Feedback?

I regularly double coat Platine paper. Diluting the second coat with
distilled water is helpful because the second coating is absorbed much more
quickly than the first; a little more solution helps considerably. Start by
adding 1/4 the quantity of sensitizer. Between coats I let it air dry from
5-15 minutes; it changes with the humidity, batch of paper, phase of the
moon, phase of my mood, etc etc, just like every other step in the process.
I then use a hair dryer on it, but dry only the sensitizer side -- dry the
front AND back of the paper after the second coat. Its important that your
drying procedure be consistent and repeatable.

>Second question : In the sodium dichromate method of contrast control, is
>any restrainer such as Hydrogen peroxide needed for the KOx #0 solution,
>that is no drops of sodium dichromate.? Is the evident grain of the pure
>Kox solution paper dependent?

You don't need a restrainer for the KOx #0 solution

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WILLIAM LAVEN PHOTOGRAPHY

Offering Platinum/Palladium printing services and workshops and tutorials
in Pt/Pd printing and other areas of photography (Zone System, etc.)

1931 23rd Street, San Francisco, CA, 94107
415-647-9432 (voice) 415-647-9438 (fax)
wmlaven@platinotype.com
www.platinotype.com

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