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From: Lesley Wischmann <[log in to unmask]>
To: Multiple recipients of list <[log in to unmask]>
Subject: OT Photographing Faded Signatures
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Hi Trail Fans --
 
I just received a copy of this fascinating article from the Associated
Press. It apparently appeared in an Idaho newspaper but is undated and
unsourced.
 
"Faded Signatures at City of Rocks revealed in high-tech photos"
 
"ALMO--An Oregon photographer is using modern, high-tech photography
equipment to find the seemingly lost signatures left by 19th-century
immigrants on outcroppings at the City of Rocks.
 
"Jim Henderson has a method to digitally boost slides to reveal eroded
signatures left on rock faces.
 
" 'My interest is in trying to make pigments visible that have seemingly
faded but are still on the material,' Henderson said. 'In the case of
immigrants, they used axle grease as ink. Eventually the carbon part of
it falls off, leaving petroleum residues, which are light orange in
color. My photographs, essentially, isolate the residues from the
background.'
 
"The process, developed by Henderson after an archaeologist dare him,
captures the graffiti on film while exposing the rock's surface to
polarized strobe lights. Although the technique was derived from a type
of medical photography used to examine microscopic tissues, Henderson
said he is the only one using the application for historic purposes.
 
" 'It's like playing 3-D Chinese checkers, because you can see multiple
layers on one surface,' he said. '(The game) is analogous to the pigment
because polarized light allows you to see everything down to the base.'
 
"Henderson took pictures of about 60 percent of the rocks. The photos
revealed 208 inscriptions, steeply exceeding the previous estimate of
61. He said he was eager to finish the job in the park and, with
permission, venture onto uncharted private properties."
--
Lesley Wischmann
mailto:[log in to unmask]
 
Visit the Oregon-California Trails Association website at:
http://calcite.rocky.edu/octa/