Re: POP choices

[Steve Shapiro <sgshiya@redshift.com>]

With Bergger films, I had found the same thing.  Longer development times
will not yield longer range nor a more dense negative.

There is a safety factor in most modern films that prevent over developing,
and restrict you from a push development [expanded development] more than
about 2 1/2 stops.  With trix - ultra expansion can be obtained up to three
stops.

Bergger has this quality and it is a good one.  To overcome this limitation
for sunlight [or UV] printing, simply plan for that and over expose the
stops.  (Answer part two)  With over exposing, or to lower the EI (exposure
index) below the ISO then to develop using the staining developer Pyro
(Pyrogallolic acid developer formulae) what it gives is a long range in the
highlights and very accomplished shadow detail, too.  But without the
original exposure, nothing can add on to the negative by development.

S. Shapiro, Carmel
----- Original Message -----
From: "Sandy King" <sanking@clemson.edu>
To: <alt-photo-process-l@skyway.usask.ca>
Sent: Thursday, August 30, 2001 3:15 PM
Subject: Re: POP choices


> >
> Just as a curiosity, have you gotten enough contrast for POP with BPF
> and developers other than Pyro? My own experience with BPF is that it
> does not respond positively beyond a certain CI to increasing
> development times, period, irrespective of developer. There is
> something about this film that causes it to shut down when it reaches
> a certain CI, and prolonged development beyond this point does
> nothing but increase b+f.
>
> Sandy King
>
>
>
>
>
>
> >Hi Carl,
> >
> >
> >This topic of pyro developed negatives to use both with POP silver and
Pt/Pd
> >is very interesting to me  because I've concentrated myself on this  two
> >methods for contact printing and discussions about this matter are
> >practically  absent.
> >
> >I use BPF with Rollo Pyro from Lotus View Camera in Expert drums and the
> >results I got until this moment are not entirely satisfactory.
> >With normal developing times  the contrast is simply not enough  for POP
and
> >I tried to give longer times but overall B+F+Stain  increased to a level
> >that  the exposure needed to UV  is to long with the related problems.
> >I've tried  as  you recommend in "The New Platinum Print" :
"strengthening
> >the developer and cut the developing time"  but I didn't solve the above
> >described problem.
> >
> >Perhaps I'm missing something concerning pyro development.
> >
> >
> >greetings
> >
> >Manuel Gomes Teixeira
> >
> >Punctum Studios
> >Portugal
> >EU
> >
> >
> > > From: Carl Weese <cweese@earthlink.net>
> > > Organization: Carl Weese Associates
> > > Reply-To: cweese@earthlink.net
> > > Date: Thu, 30 Aug 2001 11:37:26 -0400
> > > To: Alt-photo-process <alt-photo-process-l@sask.usask.ca>
> > > Subject: POP choices
> > >
> > > James,
> > >
> > > Assuming you will have access to a darkroom for film development (4x5
> > > film in trays doesn't take much space): FP4+ in PMK pyro will give you
> > > negatives you can print in POP silver, and then later print in Pt/Pd
or
> > > on standard variable contrast silver paper. Pretty good combination.
It
> > > gives high acutance if that's what you're after. As for obtaining it
in
> > > Japan, just take a couple dry packaged kits from ArtCraft Chemical
with
> > > you. Each will make 50 liters of working solution which is enough for
an
> > > enormous number of 4x5's. The mixed stock solutions have excellent
shelf
> > > life. Tri-X/PMK is another good pair. TMX and HP5 are more trouble
> > > getting enough contrast for POP processes. Of course observe proper
> > > precautions for handling pyro which is more toxic than more ordinary
> > > developers.---Carl
> > > --
> > > Web Site with picture galleries and workshop information
> > > http://home.earthlink.net/~cweese/index.html
>
>