Re: Back-exposing on plastic (was: Re: Gum transfer

On Apr 28, 2006, at 8:44 AM, Yves Gauvreau wrote:

> Katharine,
>
> my first reply on this topic was probably the cause of the
> misunderstanding,
> when I read it back now I see what you mean. With the last one I
> thought I
> made all this as clear as I can but I'll try again. If whatever you
> do back
> exposing your print fails to give you a satisfying tonal "delicacy"
> as you
> put it, may be applying a different curve would help.
<snip>

> I would certainly claim that if you maintain every variables fix
> ie. you
> don't change anything from print to print except the curve applied
> to the
> negative, you can basically obtain any tone you want between the
> Dmax and
> the Dmin of the print.

Yves, I hope seeing Chris's print comparison will help you finally
grasp what I've been saying. No, you cannot, once you've got the
right emulsion, "basically obtain any tone you want between the DMax
and the Dmin of the print" by adding a curve. With gum, you can
obtain some of the tones running between Dmax and Dmin, but not all
of them, not by a long shot, (this is what we mean when we say gum is
a "short scale" emulsion, or that no matter what you do, you can't
get more than 10-12 steps on a 21-step for gum in one coat by the
usual method-- that's assuming a normal pigment load; you can get
more, but paler, steps with a lighter pigment load, or fewer, but
darker, steps with a heavier pigment load).

And in fact, although this is a slightly different issue, Chris's
"correct curve" loses some of the tones she had in the uncurved
print, like the details in the shadow side of the building, at least
that's how it looks on my screen. I would never use a curve that
extreme, because I don't like contrasty prints; I prefer more tonal
sublety and smoothness. (I never liked Ansel Adams' work until I
discovered his earlier work, which had a lot more tonal subtlety to
it). This is not a criticism of Chris's choice of print contrast, at
all, or Ansel Adams' later preference either, only to make the point
that what is a "correct curve" is a very subjective thing, in
addition to the more important point that you can't get all the
between tones of a long tonal scale in gum just by adding a curve;
gum can only do what gum can do.

Katharine
Received on 05/02/06-12:50:21 PM Z