"Michael Scarpitti" wrote in message
om...
"KS" not.me@com wrote in message
news:WifTc.97257$M95.43550@pd7tw1no...
What are the advantages/differences between using say ABC Pyro as
opposed to
C-41 based B&W process film? I'm debating whether it is worth the
trouble to
use play around with pyro. Thx.

ABC is a very old formula, and I doubt you will have very good results
with modern films. Pyro is highly toxic and tricky to work with. It's
hard to control the staining, as stop baths and fixers will bleach it
out depending on various conditions.

Pyro today has very little to recommend it.

It's utterly amazing how little you really know Mike. The only thing you
got right was it's an old formula, but then again, so is Rodinal...

Pyro in all of it's formulations works fine with most modern emulsion films.
ABC pryo inclusive. Due to it's staining characteristics negatives
developed in Pyro print exceptionally well with variable contrast papers.
Using an alkaline fixer formula (TF-3 or TF-4), and a water bath between dev
and fix and staining can be controlled very well. A post fixer bath of an
alkaline solution enhances the stain formation. Since the developer is a
one shot process and alkaline in pH, most use the spent developer for this
bath. You do it with the lights on so you can control the staining.

While toxic, it's no more toxic than many normal household products, with
the exception that it's easily absorbed through the skin. So gloves and
dust mask are a necessity. MSDS shows the LD 50 in rats to be 789 mg to 1
kg body weight. On the other hand, a dog only needs 25 mg per kg.

I would recommend Gordon Hutchings PMK formula (Pyro/Metol/Kodalk) and his
_The Book of Pyro_ available from the Photographers Formulary and other
sources.

Pyro negatives and prints have an increase in tonality, sharpness, acutance
and separations in the highlights. This is most noticeable in MF and LF
prints, but it is also usable with 35mm. Another advantage is the stain
tends to mask the grain. This may be a benefit for 35mm by itself.

You'll only know if it fit's into your needs if you try it. Plus-X and
Tri-X seem to work well with the advantage going to Tri-X. So don't let
those who have never tried Pyro steer you the wrong way.

Jim