alt-process (for lack of a better term, other than "antiquated"), but
i'm told there's a way to do that in PS as well...i agree, boring
but, as for digital, has anyone seen irene siegal's work in person?
Herschel,
I had the same problem in Cairo when I was teaching "Manual"
Photography. Water was 32 out of tap, and there was little climate
control in the darkroom...so, even if you had one, it would be a
challenge. And, this being three years ago, we were quickly losing
supply lines...The final year, I had to bear a significant percentage
of ordered boxes of paper being ruined in customs by barbarians...it
was friggin' tragic...
But this is why I'm going alt process. Raw chemistry is almost always
easier to come by in non-western locations. And, a lot of them don't
even require a darkroon.
Herschel wrote:
I remember
well the dismay of finding out that selenium toning was ineffective.
Digital is far less labour intensive... although much less engaging.
All round, digital is just too un-mysterious... too easy. Good for my
commercial stuff certainly but missing the "Plastic" stage. It used to
be that all 5 senses were involved...
I long for the darkroom these days but the water out of the taps here
is 35 deg. C and there's no place to buy any darkroom equipment or
materials.
karl shah-jenner wrote:
from 2005
Robert
: None of your references comes from Kodak. A fine point, but quite
: important in my view. Lets look at your references:
me:
no you're right, it IS important.. and I am still dredging thu my
references to find the specific site link ..
As one researcher stated elsewhere "there is a very large literature on
fixing and washing of photographic materials. Much of the research was done
at Kodak Research Labs and is available in various scientific and technical
journals. Kodak decided at the formation of the labs not to publish in a
house organ but rather in established, peer-reviewed, journals. That made
the research immediately respectable but has also made it somewhat
scattered. Some publications, notably _Photographic Science and
Engineering_ are rather hard to find. "
But I finally found one, from Kodak, which acknowledges selenium toner was
as I said, not adequate for protecting silver. The actual Kodak article I
referred to at the time is still lost to me, and Kodak do not seem to have
it.. nor would they really make a great effort to retain it since an
admission that their product didn't do what it was claimed it would is
hardly something a company would highlight. Nonetheless, it is clear from
Kodak's article (and the NEW and IMPROVED product they had to sell in it's
place) that selenium didn't do the job. Of course, they're still happy to
market the product, after all, people buy it.
http://graphics.kodak.com/docimaging/uploadedfiles/en_A1671.pdf
"The Image Permanence Institute (IPI) at the Rochester Institute of
Technology (RIT) in Rochester, New York, extensively researched redox
blemishes in microfilms. IPI’s research showed that selenium toning did not
effectively stop the spread of redox. IPI then looked at a polysulfide
solution and Kodak Brown Toner solution in place of selenium. IPI’s testing
showed both solutions stopped the migration of redox blemishes into the
roll of microfilm. As a result of brown toning, toned microfilm has a
higher resistance to the formation of redox blemishes. The combined use of
brown toning and molecular sieves significantly enhances film longevity
even under adverse conditions. " (again, adverse conditions is key - as I
said before, anything can be archived - archiving is a storage process, not
a production process)
and another more relevant than the wishy washy Kodak article.
http://palimpsest.stanford.edu/iada/ta95_123.pdf
"In the mid 1980s selenium treatment was recommended for extending the
stability of black and white film and prints in several publications [Lee
et. al., (1984) and
Drago et al., (1986)l. On this background all RC-prints and duplicate
negatives were selenium treated at our department. Further research around
1990 showed that
the selenium treatment (Kodak Rapid Selenium Toner, (KRST)) did not
effectively protect the image silver specially in the low density areas of
photographs
[Reilly et al., (1989) 124-125 and Reilly et al., (1991), 101-1021"
"Recommendations from Kodak concerning the use of Kodak Rapid Selenium
Toner to protect the prints has varied"
again, it came down to minute sulphide impurities in the early batches of
selenium toner actually doing the protecting of the silver, later batches
of greater purity removed the sulphide, and the subsequent protection that
Kodak had used to market the product.
"The test results .. indicate problems, specially in the highlights when
using selenium to stabilise silver images. The results suggests that
polysulfide treatment should be preferred to selenium. On the other hand
selenium treated prints are generally found more attractive than
polysulfide treated prints"
regarding film treatment:
"It can be concluded that treated films are more resistant to peroxide
attack, but complete resistance with selenium calls for a more concentrated
solution or longer treatment time (25 minutes!) than normally stated"
this all leads to the statement:
"Our conclusion so far is that all duplicate negatives made of historic
negative cullections should be treated with IPI SilverLock, 1+50 for 3
minutes"
and that's the thing - Silverlock is a sulphiding agent, not a seleniding
agent.
finally, a GREAT article from someone who actually cites the chemistry for
a change rather than just talking about what someonhe else said:
http://www.largeformatphotography.info/toning-permanence.html
"Toning and Permanence of Silver Gelatin Prints By Douglas W. Nishimura,
Image Permanence Institute, RIT"
"everyone hears that bad processing is the root of all deterioration" ..
"All of this issues were ignored and people only focussed on the poor
processing. Hence, every photographer hears that bad processing is problem.
You will find that finding examples of poor processing are not so easy to
find. In fact, the major cause of deterioration is oxidation"
" Fuji found that a small amount of residual fixer in their samples
actually made them more resistant to oxidative attack. They weren't the
first people to discover this. George Eaton told us that back in the 1960s,
they found the same thing at Kodak, but didn't know how to tell people to
wash well, but not too well"
"There is nothing magic about microfilm silver (except that it tends to be
very fine grained), but the chemistry that governs what happens to
microfilm silver, also applies to paper " ("Microfilm was the first
photographic material considered to have enough value that its
deterioration warranted reseach funding and interest.")
"When we brought this to Kodak, they tried to dig back in their records for
formulations and chemical sources. They had run into something similar with
regard to stabilization processed photographs. Prints produced by users in
the field had unusually stable prints (quite resistant to oxidants), but
when they tested the processors in the lab, they didn't find any high level
of resistance to oxidants. It drove them crazy .. It was possible that
selenium toner tested by Bard et al was an old bottle possibly contaminated
with active sulfur compounds. However, we obtained a bottle of selenium
toner from the same approximate time and tested it and got no better
results. Kodak tried similar tests out and also found that the selenium
wasn't working as well as it apparently did in the early 1980s and no one
understands why."
"we did find it interesting that the long-known solution of gold chloride
and sodium thiocyanate (known as Kodak GP-1) worked pretty well. .. in the
1960s worked on a better formula that was to become known as GP-2. It
consisted primarily of gold chloride and thiourea with a few other salts
added. This formula really worked well on films and prints. Henn and Mack
observed that as they increased the gold content of the solution, they
observed no increase in the "protectiveness" of the solution, but as they
increased the thiourea content, the treated film stability went way up.
They didn't pursue the problem and simply decided to use five times as much
thiourea as gold. So here we have pretty strong evidence that the thiourea
complexing agent (that kept gold from falling out of solution) was
contributing to the stabilizing effect of the toner. Gold solutions not
containing active sulfur (such as GP-1) had no such effect if we varied the
concentration of the complexing agent. "
amazing really (the last bit) that they didn't 'pursue the problem'. It
becomes really clear that the sulphide is the protective agent, yet they
either didn't see it, or were not being very observant!
"..you're forced to draw some conclusions about sulfur. .. Just a tiny
amount of sulfur "dusted" on the surface of silver image particles can make
the silver fairly stable against hydrogen peroxide oxidation, but for
things like ozone and nitrogen oxides, actual conversion to silver sulfide
is required. Selenium will work, but a heavier dose of toner is required in
order to ensure that the mid-tones and high-lights are adequately
protected."
How about papers? Back in 1992 we had a Swiss Graduate student here doing
his MFA here. The title of his thesis was On Black-And-White Paper
Image-Stability Enhancement: Effectivenss of Toning Treatments on Silver
Gelatin Prints Determined by the Hydrogen Peroxide Fuming Test. This
411-page thesis reached the same conclusions that we had regarding toners
with film. "
it's been a long time tracking this down, but it' something that bothered
me .
karl
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