Tri-X/HP5 -- is there a differnce or do I just will it?

I have been shuffling between 4X5 HP5 and Tri-X hoping to see the difference and decide on what I want. I think I see the difference, but I don't know. Maybe I am just willing it. So I tried an experiment that could be called anecdotal. Same camera, same lens, same subject, almost the same exposure (320/400 +/- erratic shutter). Somehow HP5 is lighter? not as heavy? I don't know. The HP5 skintones looked (I know it's not a word) more marzipan-ish. The Tri-X looked, well, normal. I'm going with HP5, but I'd like to know if it just because I am stubborn and delusional, or if you can really see a difference. Something in my gut tells me that there can't be any difference.

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Dean

I'm guess they differ in HD curve shape (pick a toe, any toe) and

spectral sensitivity. These are things you can't make up for in

exposure and development. It's OK, just use what looks best to you,

we won't tell anyone...

Try the same experiment using Diafine. Shoot the negs at the same time

and process them in the same batch and then make the decision...

Scott

In 4x5, the shape of the H&D curve is different (4x5 Tri-X is TXP,

not TX), so the films do produce different results. HP5+ is actually

closer to regular medium format and 35mm Tri-X (TX) as opposed to Tri-

X Pro (TXP).

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Part of the confusion is that there are two very different films

called "Tri-X." This dates back to before WWII when the original Tri-

X was a sheet film, and smaller formats used Double-X as their

highest speed film. When Kodak discontinued 35mm Double-X in the

early 1950's, they called its replacement "Tri-X" but it wan't the

same film as the sheet film version.

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TXP (the sheet film version) is formulated for studio portrait use

with hot lights. This is one reason why there is so much nostalgia

among zone system types for the old double-X sheet film, which had a

long straight line section of the H&D curve.

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IMHO (as a TX user since the late 1950's), HP5+ is much better suited

for landscape use than TXP. Of course, that's just another way of

saying it behaves more like TX :-)

Life was simpler when I thought speed was the only choice. Scott, I

was waiting to decide on one film BEFORE I tried a new developer, but

maybe I'll just go all out, try the Diafine, and heck, maybe DDX too

then I'll make all my decisions at once from six possible outcomes.

And then I'll stop experimenting for at least 3 years. And it makes

life doubly dificult if Tri-x is so many differnt films -- I thought

that I would standardize on sheet and roll too. Thanks for your help.

Dean

Dean, if you want a simpler life, being a serious photographer is NOT

the answer! I get much better results with Ilford films than any

other. Tri-X is the only Kodak film that I would use for personal

work. Using my color densitometer, I have determined that HP-5+ has

an EI of 200 (same as Tri-X) when developed in PMK. Xtol may get

anywhere from 1/3 to 2/3 stop more 'speed' from most films, but it

has a little more fog. You may want to try PMK (Pyro-Metol-Kodalk)

developer. You can dramatically reduce the time it takes to make fine

prints from negatives developed in this developer.

Michael, PMK is on my goal sheet for 2 or 3 years from now. OK, I'm

paranoid, but I will wait until I have a semi-dedicated darkroom,

properly ventilated as I heard it is deadly poison. I don't want life

REAL simple; I just don't want to make it harder than it has to be.

Thanks, Dean

Dean, I'm continually amazed at how many people are frightened of

pyro! There are MUCH more toxic chemicals used in household cleaning.

If you follow the safety precautions outlined in the instructions

(mix outdoors or under a 'ventilator'i.e. a range hood) and don't

drink the 'A' solution, and don't soak your hands in the developer,

you will be quite safe. Whatever you do, though, DO NOT mix amonia

and bleach! The fumes will kill you in less than 30 seconds! There's

no warning labels on either of those chemicals, is there?

Oh, I know I'm irrational about the whole PMK thing, and I think the

images I've seen using the stuff are amazing -- those 'wow, I'd like

to do that' as opposed to an 'oh yea, that's nice' kind of photo. But

I'm not quite there yet. I tried DDX this week, and I'll try the

suggested Diafine next week (payday -- man is that stuff pricey).

Though it is encouraging to know that PMK isn't as bad as it is

rumored to be.

Thanks for your ideas as I try to take the next developmental (get

it?) step.

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Dean

Dean, you can buy PMK pre-mixed from Photographer's Formulary

(http://www.photoformulary.com). I just got some. I'll use rubber

gloves while I use it but aside from that I see no reason for

precautions. The most dangerous thing about PMK is pyrogallol dust;

using a liquid concentrate minimizes the risk of exposure.