U of S | Mailing List Archive | alt-photo-process-l | RE: Help! Pt/Pd probs

RE: Help! Pt/Pd probs



A quick reply:
Have you tried to print with very humid paper (to the point of being
soft/limp) *by putting 2mil/50micron polyester under (to keep the paper
humid for long exposure times) and over (to protect the negative) the
sensitized paper*? Humid paper will be both softer and faster (in case of pd
printing, w/ pt dry is faster)...
 

________________________________

From: Jon Reid [mailto:sharperstill@gmail.com] On Behalf Of Jon Reid
Sent: Monday, July 06, 2009 4:34 PM
To: alt-photo-process-l@usask.ca
Subject: Help! Pt/Pd probs


Hi all, 

Thanks to all for the advice re masking Pt/Pd prints last week. I printed
again over the weekend and the Rubylith mask worked well. The edge is a
little softer than I would like but I remember it is about the same as film
edges used to print (before I printed from digital-internegs for a few
years). Perhaps I am just used to the crisp edge of a digi-neg print.

Another problem persists though. Remember I mentioned that my father had
modified my contact printing frame so as to create more pressure because I
suffered soft bands across the frame? Well, that modification definitely
improved things, but I am still getting, even with incremental exposure,
soft areas.

I am printing 5"x7" pyro developed Tri-X in the middle of an 11"x14" piece
of Cranes Weston Diploma Parchmont (old stock bought from Bostick +
Sullivan, not the newer stuff from Butler Deardan). I finally decided I
wanted to use this paper in this size for this series which I hope to
exhibit.

Salient points:

1) I've only ever printed Pt/Pd on Arches Platine before this and i've never
had softness problems even before the frame modification.

1.5) The paper was buckling quite a lot when being coated. I reduced my drop
count by a reasonable amount and am using 6 drops sensitiser, one drop
contrast agent (NA2 or whatever it is) and 7 drops metals.

2) By incrementally building up the exposure (2mins exposure, lamps off for
1-2m; 2m exposure, lamps off etc) I can significantly reduce the
corrugations that appear in the paper after the 10m exposure. I still think
the problem is connected to paper weight and heat in my pizza oven.

3) I am resting the paper for a full ten minutes on a plastic rack over a
tray of water after blow drying the sensitiser, and resting again for 5
minutes after exposure is complete.

4) I am centering the paper/neg etc in the printing frame. My last idea for
remedying the problem is to place the paper sideways in the printing frame
right underneath one of the springs.

5) I have to basically stop printing this series until I solve this problem
as I simply cannot afford to keep printing otherwise perfect prints that
have small soft patches on them. Any paper or Pt/Pd chemistry I need I must
ship from the US and it is very expensive. I have a stack of ten or so that
I must throw out that could otherwise be hung in the gallery.

I'm getting desperate. I have upwards of 20 negs to print perfectly and more
to shoot for my first solo show but it's hardly off to a great start....

It's late now...

Thanks for listening,


Jon