From: Randall Webb (randall.webb@lineone.net)
Date: 03/24/01-01:04:58 AM Z
----- Original Message -----
From: Ginger Sheridan <sheridan010@earthlink.net>
To: <alt-photo-process-l@usask.ca>
Sent: Friday, March 23, 2001 9:39 AM
Subject: "Sabbatier" of Palladium
> I have been printing Palladium for years. I use B&S kits, a velvet brush.
I
> have had no problems. This week I coated a new batch of paper, using a
> glass rod. I coated it at school, which means I did not have as clean a
> space as at home - but I was careful.
>
> When I developed the prints, the dark area glowed a sort of metallic
copper
> color. It did not go away with fixing. I have never seen this before. It
is
> sort of like Sabbatier. Only in the dark shadow areas are light and
> coppery. The rest of the image is fine. I printed another image at the
same
> time/same conditions which had no shadows. It didn't have any of this
effect.
>
> At first I suspected the glass rod (sorry B&S) but then I had a piece of
> paper from the same batch that was coated by velvet (I have been using the
> same velvet for years, so that is not it). It did the same thing with the
> shadow area of the print.
>
> Any insight? It was very cold (for Florida) - so perhaps my chemicals were
> cold when coating. Would that have done it? I know of no metal
> contamination - nothing I used was metal. Could there be a trace of other
> alt processes (cyanotype or Van Dyke or Sprint B&W chemicals) in the
> container I used. If so, it would have been minuscule - could that have
> done it?
>
> Thanks for any suggestions. I have coating another round and will print
> next week to see if it was a fluke.
>
> All the best,
>
> Ginger Sheridan
Perhaps I may quote from Dick Arentz from his "Outline of platinum and
palladium printing" without breraching copyright.
He says " Pure palladium has a tendency to solarise under super maximum
exposure. This property can be used be used creatively, if you prefer, for
variations from the standard palladium print.To avoid solarisation, coat
palladium heavily. possibly with sizing in the sensitizer and expose shadows
to 90% blacks,( the brush strokes will probably solarise). Also, increasing
the proportion of metal to sensitiser may help."
He might also have said you can avoid the problem by not using bullet proof
negatives as required for POP and using instead sensible ones(0.9 - 1.1 net
density ) as used with DOP.
He also says" One of the pitfalls in the study of any photographic science
is the tendency to produce some "techno-fascists", more interested in
manipulating materials than engaging in visual expression. Photography is,
however, an inexact science becauseof the many variablers beyond our
control."
But then we all knew that, didn't we ? Sounds like good old fashioned old
process philosophy to me.
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