archivalness

In some relation to recent discussion of possibility of significant
level of residual iron, I'd like to say a couple of things.

Until the relationship is experimentally established, we have no idea
whether different clearing methods leave significantly different
amounts of iron in the paper. We also have no idea whether the
chemical form of the residual iron, if any, would be same across
different techniques. We also do not know whether these make enough
difference in life expectancy. That is, if there's another mechanism
of degradation that is faster than iron related, this issue would be
irrelevant, at least until the other problem is solved.

One thing I've been saying is that, testing for residual iron is easy
and simple.

That we have a print that's still good and a print that's gone bad in
some uncontrolled condition means little in statistical sense, partly
because of uncertainty of the processing variability, and that in
storage condition, which has huge influence on the degrading rate of
the image.

Definition of archivalness is also becoming empty. As you see on
various posts, people here are discussing the condition of the
image/support within 3-30 years span at a normal storage condition
(the worst I've seen here in bathroom). This is not what I call
archival, but the definition varies. The paper conservators, for
example, are concerned about much longer time span. I understand that
the level of archival concern varies depending on people, but throwing
out examples with inconsistent definition of archivalness is not going
to provide much insight about the issue.

Finally, I agree with Sandy that silver image is not very stable for
display or long term storage unless it is toned.
Received on Tue Mar 28 19:12:06 2006