Because of other demands on my time right now I've only made one test of
pyro development--four sheets of 8x10 HP5+, but the results were
dramatic. The negatives print in Zia with far more snap and tonal
separation than I've gotten from this film with normal developers, and
yet can handle a longer total range at the same time. Interestingly,
combined with the Zia self-masking, I got excellent prints from very
different tonal range scenes without changing the paper contrast:
negatives from quite flat lighting made lively prints in 10 minutes,
while a backlit snow scene with extreme contrast developed at the same
time delivered a fine print with excellent detail throughout at the same
paper formulation simply by extending the print time to twenty minutes.
I suspect that a shorter film development would have again delivered a
full scale print, at a shorter exposure, without changing the paper
formula. More tests will follow asap.
Developed conventionally, HP5+ has delivered quite gritty texture in
very dense highlight print areas compared to TXT and FP4+: the pyro negs
show a reduction in this grittiness, but it's still there. I'll be very
interested to see TXT results, and also whether further tweaking of the
HP5+ development can smooth the high values--I think the first test was
a bit underexposed and overdeveloped.
So, PMK pyro does wonders for turning HP5+ into a viable and versatile
"platinum film". Other reactions await further tests with other
films.---Carl