Clearing Problem with Platine
Stephen R. Harrison (stephenr@silcom.com)
Sat, 5 Oct 1996 16:57:56 -0700
Not having much success with clearing Platine in the past , I once again
tried some Arches Platine Paper for some platinum/ palladium prints. For
clearing baths I used three initial trays of Kodak Hypo Clearing Agent . I
mixed these solutions by making what Kodak calls a "concentrated stock
solution" of one US gallon of water in 1 lb of the package contents. The
package instructions call out that this concentrated stock solution be
diluted one part with 4 parts of water when used thus making a net of 5 US
Gallons of solution Instead, I diluted it with one part of water to one
part of concentrated stock solution. I let the pt/pd prints remain in the
solution for probably 8 minutes each for 3 baths. Then put the prints in 2
more baths of EDTA tetra Sodium from B&S ( 1 Tbsp per 32 oz water ) and
let them sit for 8 min each. That followed by a wash in tap water for 30
minutes. The dry prints looked great the next day but a week later about
15 or so 1/4 " and sometimes 1/2 inch in diameter spots appeared . The
spots are fairly uniform in tone and there is no central nidus of black .
They are a light brown in color. I used sodium dichromate in potassium
oxalate as a developer and for contrast control. I therefore did not use
any of the #2 potassium chlorate . I used Hake brushes for application of
my sensitizer so I don't think the problem is one of contamination with
steel or metal. I strongly suspect the problem is with clearing especially
given that the spots did not reveal themselves for a week .Any suggestions
?
Stephen Harrison