I have running tests with pure
palladium recently and have found (as one would expect from the
literature) that heating potassium oxalate developer up to the steaming
point, will result in siginificantly warmer tones. I don't really like
working with the hot developer because of the fumes, but I have minimized
the problem by using a sheet of clear plexiglas to cover the tray after I
add the developer.
The only downside is slightly enhanced grain -- which some people might
like for certain types of photos, and some black "bathtub ring" in my
trays. I assume this is sensitizer runoff due to using more sensitizer
than necessary. I will continue to explore what is the minimal amount of
sensitizer required for this method. However, it doesn't seem to be much
of a problem with room temp. developer. It becomes a problem when it
leaves little swirls of "bathtub ring" on the paper, though it has always
been near the edge of the paper where the developer sloshes back on it
when rocking the tray.
The blacks are still dark and rich using either the room temp. developer
or the hot developer. In other words, the alleged run-off is not
degrading the image.
That's it for now. More news as it happens.
David Fokos