U of S | Mailing List Archive | alt-photo-process-l | RE: archivalness of gum

RE: archivalness of gum



Ryuji, can you help with this?
	I was loosely following this thread when I read about ghost images
produced supposedly by some of the platinum or palladium coming off on the
interleaved papers.  In the very beginning of my relationship with my local
framer (before I corrected him) he used to put "moisture barrier" board
behind my silver gelatin prints.  When I went to remove the mb boards I
found faint images of the prints visible on the mb boards.  I had no idea
how this happened.  The prints were not hung or stored in bright light.  
Could this be what was seen with the pt/pd prints or did someone actually
test the faint images on the interleaves to confirm that they were pt/pd
metal?  
	HOLIDAY CHEERS FROM BARBADOS!
			BOB

-----Original Message-----
From: Christina Z. Anderson [mailto:zphoto@montana.net] 
Sent: Friday, December 21, 2007 12:38 AM
To: alt-photo-process-l@usask.ca
Subject: re: archivalness of gum

Diana,
I am not sure how much time it took to transfer, but it seemed like it was
decades.  Also, it was a faint ghost of an image, and I would wager a bet
that even with the transfer of some of the metal to paper in contact, a
platinum print is still way up there in archivalness, in the same category
as carbon and gum.

If one thinks about it, look at BW paper--I've seen Becher Typology Water
Towers hanging on the walls of the Walker in Mpls that already were showing
brown spots and silvering out and such.  And then think of albumen prints
that turn yellow with time.  One reason gum printing was so exciting in the
beginning was that it was an answer to the fading of silver nitrate based
prints at that time--people wanted something that had more permanence than
what they were finding in a few short years was fading.  Luckily I xeroxed
those discussions from the early 1860's when gum and carbon came on the
horizon.  There is no silver to fade or fox or spot, just pigment and gum
and paper and very little dichromate left.  Well, and now some sodium
hypochlorite in Marek's prints :)

So by comparison, so I thought, gum, carbon and platinum were the best.  OH,
and guess what--if the gum layer is on top of the pt/pd print, it would
prevent the ghosting from occurring by acting as a barrier to the paper in
contact with the print, so in fact it should HELP with any shortcomings
pt/pd may have!
Chris

Christina Z. Anderson
Assistant Professor
Photo Option Coordinator
Montana State University
Box 173350
Bozeman, MT  59717
406.994.6219
CZAphotography.com 



__________ NOD32 2740 (20071221) Information __________

This message was checked by NOD32 antivirus system.
http://www.eset.com