There is platinum and there is platinum... Pure platinum had exposure times
very different in my own tests.
It may not be important here, but these days when people say "platinum"
they mean "mostly palladium"
>Would you describe the "Berkey K&L Metal halide" in more detail?
A nice tabletop job I bought new ca. 1980. They stopped making them a long
time ago I think. It has a light integrator which can be filtered for the
process you use, as explained in some of my books. In practice, with
monochrome printing, you get away with anything.
It has a vacuum frame that requires a bleeding valve for carbon transfer as
mentioned previously. I would not try to make fine prints without a vacuum
frame after seeing the difference it makes, especially with negs of any
size.
gotta go
Luis Nadeau
NADEAUL@NBNET.NB.CA
Fredericon, New Brunswick, Canada