Re: Gum tonal range (was Miracle size for gum)
Wow, this is like Alice in Wonderland; the question arrived after I
sent the answer.
Yes, you're thinking right: with multiple printing there are no
limits on what gum can do. Isn't it a wonderful process?
On Oct 12, 2009, at 4:15 PM, phritz phantom wrote:
i've been wondering, is this discussion about exclusively about one-
layer-gums? i think it is.
single layers of gum have a rather short tonal scale, i think we
all agree on that. but so what? hardly anyone actually prints
single layer gums, except for testing, experiments... so with the
inifinite amount of layers i can add, the tonal range of gum is
only limited by the pigment. and the smoothness / contrast depends
on how good those layers are coordinated.
katharine, with your .75 density range, did you mean single layer
or finished print?
the other thing is, that all tonal ranges are a continuum between
black and white. there aren't any steps in reality. even in an
extremely short tonal scale is every single shade of grey present
in it. it's just a matter of a suitable negative to print them.
or am i getting something wrong here?
Paul Viapiano schrieb:
I've now worked with several different DRs with *my* gum prints...
Although the lower DRs are great for one-layer prints, I find the
pt/pd negs (1.8 and up) give me more breathng room for accurate
separate exposures for highs, mids and lows. It's easier to divide
a 7 or 8 min exposure (I use the sun) into separate components
than a 1.2 neg that has a base exposure of 2 - 2 1/2 minutes.
----- Original Message -----
From: "Loris Medici" <firstname.lastname@example.org
To: <email@example.com <mailto:alt-photo-process-
Sent: Monday, October 12, 2009 12:38 PM
Subject: Re: Gum tonal range (was Miracle size for gum)
For the sake of clearness I'd add that no one had made such a
translation as I understood the conversation. The subject was "what's
the *ideal* negative DR" to print gum, and when somebody says "gum
prints 2 stops", what I understand personally is that they're making
the assertion: "gum need a negative density range of log 0.6", which
is obviously a false statement. Gum is so flexible that one can print
perfectly from a negative with a density range 0.6, or 1.0, or
1.5, or even 1.8 as Marek shows, (fill the rest and in between),
the necessary adjustments in emulsion formulation / exposure and
development are made. That's my whole point - which I'm sure you'll
agree. What's best depends on the practitioner and their particular
workflow / strategy of preference. Hence the (*)s to mark "ideal"
above; there's not an ideal DR in the practical sense. Especially
after some amnt. of experience...
2009/10/12 Katharine Thayer <firstname.lastname@example.org
> I was not arguing against the use of step wedges, for heavens'
> I was simply arguing against the translation of number of steps,
> number of "stops" to a print density range by multiplying by .15
> Hope that point is now perfectly clear.