Film with longest straight-line curve for extreme pulling

greenspun.com : LUSENET : B&W Photo - Film & Processing : One Thread

Can anybody advice the film suitable for extreme pulling, that has very long straight-line part of characteristic curve? I realize that speed and contrast both drop while pulling both effects are desired; the acceptable speed should be somewhere in 6-25 ISO, the contrast (gamma) somewhere in 0.35-0.45. The subject brightness range is ca. 9 stops from important shadows to important highlights; to have 1-2 extra stops as a safety margin before noticeable shoulder would be great.

I have access to most Kodak/Ilford/Agfa films, excluding TechPan and discontinued APX25. In any case I'll do my own testing, (the first candidates are Ilford Pan 50, D100, FP-4+) but I'll appreciate if somebody gives me some guidelines.

The grain doesn't matter.

Thank you! Andrey.

-- Andrey Vorobyov (AndreyVorobyov@mail.ru), September 12, 2001

Answers

This is something I have not done myself. I know that Bruce Barnbaum uses Tri-X sheet film developed in highly diluted HC-110 to obtain as much as an N-6 contraction. I also know a photographer in California who does the same thing with T-Max 400 and highly dilute T-Max developer.

-- Ed Buffaloe (edb@unblinkingeye.com), September 12, 2001.

See the discussion "Mortensen and gradation" in the archive for Processing Film.

-- Ed Buffaloe (edb@unblinkingeye.com), September 12, 2001.

Thanks, Ed. It is curious that nominal speed of both this films is 400. The succes probably should be attributed to very long curve of the films: I've read somewhere (at your web site?) that HP5+ in diluted Rodinal offers up to 14 Zones. Interesting, can films with slower nominal speed give the long line also?

-- Andrey Vorobyov (AndreyVorobyov@mail.ru), September 12, 2001.

Not being an expert on film contraction, I can't answer your question about using slow films. Perhaps someone else will offer a response. You might consider a staining developer such as the pyrocatechin formula Ansel Adams gives in his book THE NEGATIVE (which is said to handle a 14-stop range).

-- Ed Buffaloe (edb@unblinkingeye.com), September 12, 2001.

Andrey:

I have found that T MAX 400 sheet rated at 200 or a bit less, then developed in split D-23 for 9 minutes in Sol'n A at 20 deg, then 3 Min in Soln B gives me excellent negs for Pd/Pt printing on Palladio paper. Try 11 min in A for perhaps another zone of shadows.

This give a VERY wide range and can print nicely on VC/MC paper with a #1 or 0 filter.

-- RICHARD ILOMAKI (richardjx@hotmail.com), September 12, 2001.



HP5+ in D-76H 1:3 at the usual 1:1 time gives roughly N-4, EI 160-200 or so, with a straight curve shape.

-- John Hicks (jbh@magicnet.net), September 12, 2001.

The developer is as important, if not more so, than the film in getting an extended range. I'm surprised that no-one has mentioned Tmax developer (not the RS version).
I don't like it for normal use, personally, but Kodak's data sheets show that it gives a very extended straight line characteristic with Tmax 100 film. The published curves show an almost 10 stop range with no sign of a shoulder, even at high gammas.

-- Pete Andrews (p.l.andrews@bham.ac.uk), September 13, 2001.

> developer is as important, if not more so, than the film in getting an extended range

That's a very important point. Some developers which produce a bit of a shoulder in normal usage can just block up (curve goes flat) at a rather low density when they're used for a short time or high dilution for a strong contraction. While the result is a much lower density on the high end, it's a no-contrast detailless density.

-- John Hicks (jbh@magicnet.net), September 13, 2001.


Gentlemen, thanks for everybody who replied.

-- Andrey Vorobyov (AndreyVorobyov@mail.ru), September 17, 2001.

Moderation questions? read the FAQ