Re: Gum-Platinum

JEFF STANFORD (jeff.stanford@mailbox.swipnet.se)
Tue, 19 Dec 1995 23:30:43 +0100

Judy wrote Dec 19
>Two recent queries -- about cyanotype on ceramic and gum on platinum are=20
>so far unanswered. Perhaps the following comments will shake out some=20
>more definitive info somewhere along the line:
>
>Printing a layer (or more) of gum bichromate over a finished platinum or
>palladium print was an early 20th century pictorialist strategy. The idea
>was to get the delicate highlight definition of platinum/palladium while
>beefing up the shadow density or "body" of the pl/pd with a layer of gum.=
=20
>Note by the way that a pictorialist goal was generally to *subdue* shadow
>detail!=20
>
>Various dictionaries of the period mention the topic; Paul Anderson has a
>chapter on it in "Technique of Pictorialist Photography", but it is almost
>entirely lacking the kind of details that would interest us, dwelling
>rather on issues like calibrating skin tone with the linen of the sitter's
>collar. And no mention of preshrinking paper before doing the platinum
>print so the gum coat would register. In general, a lack of register in
>the second coat that would drive us wild didn't seem to, so-to-speak,
>register with the pictorialists.=20
>
>Their paper may have shrunk less but soft focus was anyway style & goal.
>As Anderson put it, "faulty outlines may often be remedied by a few
>touches of a pencil on the finished print." Got that?=20
>
>Stieglitz, also Steichen, did gum over platinum (Moonrise or some sky
>phenomenon over Mamaroneck, The Flat Iron Building, etc.), but I could
>never figure out how they got color in the otherwise blank skies -- maybe
>they printed the gum with the positive.(?)

I have worked with Gum over platinum/palladium with quite good results. I
found that the platinum/palladium print gave me the fine detailed image,
while the one or two layers of gum gave me an added dimension. The fact
that I might only need two printings instead of the six layers of gum helps
avoid the shrinking problem.

The bit about "the faulty outlines..." is something that might be noticed
if there has been shrinkage. Since it will only be obvious around any
borders it is sometimes easy to retouch with a pencil or watercolors.

I might have misunderstood you with the question about getting color in=20
the blank skies but it is quite simple. If you use Steichen=B4s THE FLATIRON
BUILDING as an example. First he would have made the platinum print where
perhaps the sky was lighter, then a gum print with a long enough exposure
to leave color in the sky. He probably sprayed water around the center of
the print to lighten that, maybe even brushed it. Later when the print
was dry he painted the lamps and other highlights with watercolor.

I hope this helps.

I have started some WEB PAGES of my own so have a look.

Jeff Stanford
Petrejusv. 32=20
121 38 Stockholm, Sweden
tel:(+46)(0)8-659 86 09
e-mail: jeff.stanford@mailbox.swipnet.se
Internet address: http://www.algonet.se/~photogum
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