> Keith, I have a question. I am new to the list and do not yet know how to
> post to the entile list. I met you at Dick Arentz's workshop last April in
> Scottsdale. You had some beautiful PT/PD prints from 4x5 polaroid type 55
> negs. I was wondering if you can tell me how you exposed and developed the
> negs, and how you printed them to get such beautiful depth and tonality. MY
> type 55 negs seem rather on the thin side. Do you intensify your negs???
Hi Bob, I am CCing this to the list.
I think that the key to using Polaroid Type 55 P/N for Pt/Pd
printing is to be sure to give it plenty of exposure. It has an ISO
of 50 for the print and 25 for the negative. Since you don't have the
development control that you would have with regular film, I have
found it useful to adjust exposure based on subject contrast. For
example, a high contrast subject (SBR=9) might be exposed at ISO 25,
while a low contrast subject (SBR=5) might be exposed at ISO 12.
A normal subject (SBR=7) would be exposed at ISO 16 or 20 which is
about 1.5 stops more than if exposed for the print. I usually use a
well exposed Type 55 print as a guide for the negative increasing
exposure by 1 stop or more depending on subject contrast. If working
in the field, I remove negative exposures from the Polariod back without
processing to be developed later in the darkroom. I haven't found it
necessary to intensify Type 55 negatives.
The prints you saw at the workshop were straight palladium made on
Masa paper using very little restrainer. Palladium is capable of
rendering very subtle highlight detail especially with negatives of
sufficient range to print with little or no restrainer (particularly
potasium chlorate). Be sure not to skimp on coating. Use up to 1ml
of solution for printing a 4x5 negative. Ideal amount will depend on
absorbency of the paper, coating method and ambient humidity ( and
probably a few other factors).
> In addition, rumor has it that you are working with Dick on a revised edition
> of his text.
True, I am helping Dick with a chapter on papers.
Regards,
Keith
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Keith Schreiber, Rights and Reproductions
Center for Creative Photography, University of Arizona
PO Box 210103, Tucson AZ 85721-0103
Fon: 520-626-5164 Fax: 520-621-9444
Email: keith@ccp.arizona.edu
WWW: http://www.ccp.arizona.edu/ccp.html
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