<SNIP>
I agree with Carl. That it is often referred to as bronzing in palladium as
well as solarizing. It is interesting that you point this out because it
caused me to think about the effect more and I think it may be related to
the plating out effect.
Here's my latest theory I just thunk up. What happens is that there is a
thin coating on the surface of the paper, not down in it. Because of this
the metal in effect does start to shine up, but only partially and it is
transparent as well. If you ever seen a lightly silvered piece of glass,
you can see through it, one of the resons for painting it black on the
back. Since it is transparent it shows the underlying image which may be
slightly brown, thus the "bronzing" effect.
If for instance it is platinum and there is a deep coating down in the
paper, but also a thin coat on the surface, you get a silvery haze showing
the black underneath. I have looked at hazed prints under a microscope and
you can see the metal shiny in pools in the arroyos (gullies, to the Anglo
world) paper.
This theory would also explain solarization in the simpler terms. Let's say
you have a thin surface coat with none underneath down in the paper.
Exposure would produce the shiny effect, the shiny is transparent like
those funny mirrored sunglasses. Since there is no underlying black image,
the image reverses. In effect, showing the white paper underneath. In areas
of less exposure, the metal doesn't shine up and makes black particles
which trap rather than reflect light, thus the lesser exposed areas are
blacker.
>I've also found that sometimes it appears when the print is still wet and
>remains, though it can disappear on drying, while sometimes you don't see
>it on the wet print, but it appears when dry. I even have a sense that
>sometimes it appears in time, not at first, but accruing (perhaps in a way
>like the plating out in shadow areas of old silver gelatin prints).
Got to think on this awhile. I've seen bronzing go away with a light
coating of a matt spray. It somehow optically interferes with what is going
on. Perhaps akin to seeing no bronzing when wet and then seeing it when dry.
--Dick Sullivan
Bostick & Sullivan
PO Box 16639, Santa Fe
NM 87506
505-474-0890 FAX 505-474-2857
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