Re: Best CI for process

From: Etienne Garbaux ^lt;[email protected]>
Date: 09/30/05-10:54:02 PM Z
Message-id: <p05210602bf63bdefac92@[192.168.1.100]>

Sandy wrote:

> So let me ask again. What film/developer/agitation/temperature
> combination should one use for N development of in- camera negatives
> when the density range required for scenes of normal contrast is log
> 3.0 or above?
>
> And what should one do when the scene requires N+ development?
>
> My best estimate for most common films is that you can't get there from
>here.

I don't understand the question. The DR of the negative that just "fits" a
given printing process doesn't change with the scene contrast -- it is a
matter of (1) FB+F plus the image density necessary to get up off the toe,
and (2) the Dmax of the film at the shoulder. Neglecting the small rise in
FB+F that accompanies longer development, one just develops until the
highlight densities are log D 3.3 or whatever.

Note that users of staining developers may find that the increase in FB+F
is NOT negligible. (Ditto constant-agitation developing, but to a lesser
degree.) M-Q or P-Q developers, or even the non-staining pyro formulae,
used with intermittent agitation, do not have this problem. I develop in
glycin, which is perhaps the least fog-prone developing agent known, and
have never had any problem, even using constant agitation for 30+ minutes
at 75 degrees F. [Side note: beware of any glycin you receive that is
darker than a sheet of Crane's Ecru paper -- although many internet sources
say it works fine, IME it does not. It should be just barely off-white.
I'm speaking from extensive experience here -- I suspect I've mixed more
glycin developer since commercial glycin developers have been off the
market than the next 10 glycin users combined.]

If one's film and/or developer will not produce the required highlight
density (or will not produce it without excessive FB+F), there is still
hope. Super-proportional intensification (if the shadows are already at
the correct density and the highlights are insufficiently dense) or
super-proportional reduction (if you expose more to get the highlight
densities up where they belong and the shadow densities are too high), or
both, can expand DR by log D 1.0 or so. I have even made HP5+ negatives
with a DR of 3.0 this way, although I don't care for the film and stopped
testing.

Best regards,

etienne
Received on Fri Sep 30 22:54:53 2005

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