FotoDave@aol.com
Mon, 18 Jan 1999 21:24:08 -0500 (EST)
>> I know most of this stuff doesn't have easy
answers, but still.. the questions are killing me. I'll go easy and ask
only a few of the many questions I have right now.
Hi Adam, I will also try to go easy and try to answer very briefly because I
get complains when I get over-enthusiastic and talks about details.... :)
> First, can somebody recommend a paper that allows fine detail to be
> retained?
I have used Canford Snow White, Mi-Teintes and Arches hot pressed watercolor
paper, all giving me very fine details.
In general, for fine detail, use paper that is microscopically rough but
macroscopically smooth. These are probably terms that only I use for
describing paper for gum, but it will help in your selection of paper. To
explain it briefly, microscopic roughness can be felt with your fingers while
macroscopic roughness can be seen easily (that is, the hills and valleys can
be easily seen).
If you know physically what's going on, then you can do magic. For example, I
have used Mi-Teintes which is macroscopically rough, so it is normally thought
of as difficult to hold details. The valleys would hold more gum so exposure
cannot harden the gum through the base. Knowing this, I dilute the gum mix
with more water or dichromate so that the mix is "thinner." This causes the
emulsion to go smoothly across the vallyes and hills and thus is able to hold
details.
Of course one might want go the other way and deliberately wants this texture
to show.
> I've heard, many
> times, that gum can do detail like platinum - now I ask, how? Multiple
> coats are the target.
Most people who say that gum cannot do details are confusing resolving power
with tone separation. If you take a piece of film and just enlarge it slightly
so that you can just see some grains in your enlarged negative, you will see
all those grains in your gum print. In other words, gum emulsion has high
resolving power and can hold all the details.
The real problem is many people who try gum haven't studied it enough, and
they make gum prints where there is compression of highlights, midtones, and /
or shadows. When you lose details, some areas that are separated become one
big mess, and they call this "lack of details."
The secret is to do nice separation through multiple printing. One-coat is
certainly possible but more difficult. The reason is that gum is very short
scale, so exposure and negative density matching must be *exactly exact* and
assuming there is no change between your coating of test strip and your final
print, etc. etc. Otherwise you will lost some details.
Dave
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