You probably thought no one would admit not knowing what a "reverse
osmosis filtration system" is, but I do (admit) and do not (know), so I
hope you will fill us in on at least the big picture....
> As a test, I soaked a few of the precipitate-covered prints in trays of
> distilled water and all of the deposits were removed! This may mean that the
> chemistry should be mixed with distilled rather than water from the reverse
> osmosis system,and/or that I should be rinsing in distilled water between all
> steps in the developer/clearing process. I'll be running a few tests to see
> which technique provides the most satisfactory results. In any event, it has
> become obvious that plain tap water has a mineral content too high for the
> mixing of chemistry to be used with Platine. It's interesting that this
> problem has not manifested itself with other papers.
Is it possible that a distilled final rinse would be adequate, which is to
say is it possible precipitate comes from wash water, rather than the
"chemistry"? Some years ago I got a white precipitate on blacks in
photographs made on shiny Brovira fibre paper, but problem began abruptly,
ended abruptly. I assumed it was a vagary of the water supply. I found
that final rinse in distilled before drying did solve the problem, and the
already-dry prints cleared up by resoaking, then rinsing in distilled.
> EDTA...big topic of discussion on a talk show of O.J. talking heads that
I had the
> misfortune of hearing over the weekend. Seems like there was some found in a
> blood sample at the scene. Isn't chemistry excellent?
It just goes to show, platinum printers are dangerous....
Judy