To my knowledge, the paper is only available in 33"x40" sheet sizes. I
don't have any experience with the Bienfang 360 (though I would certainly
be interested in hearing from someone who has!), but I have spent the last
month or so experimenting with the Arches Platine. Martin Axon, the
fellow who worked with Arches to develop this paper, sells the paper for
$6.50 per sheet. Martin's phone # is 203.245.7674. Please tell Martin
that I sent you.
All chemistry is from Bostick & Sullivan.
A little history:
When I was printing about 10-15 years ago I used to use Arches 140lb.
hot-pressed. I really liked the weight, and I was able to get the most
amazingly rich black - much darker than with any other paper. Well, as I
am sure you know, the paper sizing changed and this paper is no longer
any good for platinum printing. For this reason I was very excited when
I learned, a year or so ago, that Arches was working on a paper for
platinum printing. And finally, about a month ago, it just became
available. In any case, one of my objectives was to match the Dmax I
was getting on the old Arches. I think I have been able to come close
enough for my satisfaction. The black is very rich. The tone is warm,
though not overly so for my taste. Less warm than Shillea's prints, for
instance. I will be trying some cold tone developers soon as well. The
paper is not at all delicate when wet, and it drys fairly flat. I can
get very good detail and crispness from the sheet as the surface remains
pretty smooth, even trhough processing.
Here then follows the results of my experiments to date.
Ferric Oxalate Formula
17 grams Ferric Oxalate
1 gram EDTA
3 grams Oxalic Acid
63 ml. Hot water
Standard Emulsion Formula for an 8x10 print (for each of 2 coats):
14 drops standard Palladium solution
2 drops standard Platinum solution
14 drops ferric oxalate solution
1 drop Hydrogen Peroxide mixed 1:1 with water
I coat this on to the paper using a 3/4" diameter acrylic tube to spread
the emulsion. I then let the paper dry OVERNIGHT. I do not blow dry it.
Letting the paper dry overnight is responsible for the smoothness. Blow
drying seemed to produce a more grainy result. Despite the paper's heavy
weight it does not absorb the emulsion very aggressively. You will note
that I am using only about half as many drops of emulsion than I would
normally use for this size print.
The next day, I mix up a second batch of the emulsion, and this time add
3 drops of Polyvinyl Alcohol. I coat the paper in the same way as the
first coat, and again, let the paper dry OVERNIGHT. Doublecoating is
essential to getting the Dmax. Without doublecoating I was getting
solarization (probably a result of the thinness of the emulsion layer)
and no real deep black.
I print using a nuArc 26-1K mercury exposure unit, and develop in 70
degree Potassium Oxalate. I clear in Kodak Hypo Clear, which is a mixture
of Sodium Sulfite, Sodium Citrate, and EDTA.
Finally, I like to dip the print in a 1:12 solution of Liquitex Gloss
Medium/water. This doesn't produce any noticeable gloss to the
print, but it makes the blacks richer.
Notes:
To change contrast, you have to use developer additives such as
Hydrogen Peroxide, Sodium Dichromate, or Potassium Dichromate. Using
Potassium Chlorate in a second Ferric Oxalate solution (the usual
meathod for contrast control) causes incredible grain. Hydrogen Peroxide
in the emulsion doesn't seem to do much.
I have used up to 50/50 mixes of Pd and Pt without a very noticeable
difference. If you use too much Pt you will get severe grain, very long
printing times and increased contrast.
Ammonium Citrate developer did not work well for me - it resulted in
some grain problems - though I will be re-cheking this finding in the
next week or two, because I don't think it should make much of a difference.
The clearing process is a bitch. Since the paper was allowed to dry
overnight, the emulsion has a tenacious grasp on the paper. Arches
has always been more difficult to clear anyway. The Hypo Clear seems to
help quite a bit in this regard.
I have tried drying with a hair dryer and then humidifying the paper. I
was definitely getting smoother tones than without the humidification. I
was also getting a printing-out effect. I do not get that with my
current formula - so while the paper may absorb some humidity overnight,
I don't think this is the reason for it's success. I don't get any
deeper black if I humidify the double-coated paper that has been allowed
to dry overnight.
By the way, my images are not flat and sunken in as one might expect from
letting the paper dry naturally. As I said, the Arches is not a super
absorbent paper.
Well, there you go! Good luck! I would be very happy to hear of some of
your experiments, and preferences for papers, emulsions, etc.
- David Fokos
beakman@netcom.com
> 3) If money and complexity are not the issues, what is the absolute "best"
> (in terms of short exposure, safety, stability etc..) light source for the
> process? Where to buy it? Does anybody know about or have experience with
> the pulsed-xenon lights?
> 4) I read somewhere on Usenet that Palladium increases grainniness. Is
> there any quantitative measure for the extent of this effect as a function
> of the proportion of Pt/Pd? I am concerned about this because the
> expression I am after, in the particular prints I want to make, strongly
> requires extreme sharpness.
> 5) Aside from cost and tone is there any disavantage to using only
> platinum? Luis mentioned that the DMax is lower for Pt than for Pd? Can the
> DMax be controlled by treating the paper? To what extent the DMax can be
> improved by Pd before running into grainniness (if such an effect does
> indeed occur)?
> 6) Are there special methods for local value control WHILE printing
> (dodging and burning) for the process? I read that Paul Strand used a
> magnifier to burn. Are there any light sources out there powerful enough
> (in the right part of the spectrum) to allow traditional local value
> control while printing.
> 7) Any recent news on an EPA crackdown on the sales and use of oxalates (or
> other chemicals related to the process)?
>
> Thanks.
> p.s. While reading the alt-photo-process archives, I cut and pasted
> material I found relevant to Pt/Pd printing into a file. Any Pt/Pd process
> beginner who wants these assembled clips can just ask me to E-mail the
> file.
>
>
>
> ______________
> Edgar Choueiri
> EPPDyL
> Princeton University
> choueiri@princeton.edu
>
>
>