Re: daniel smith gum
/"i dilute it 1+1 for use (a ~16% solution). because i found that the
33% solution gets sticky too quickly when painting on the emulision."/
when used 1+1 with the dichromate (i forgot to add)
phritz phantom schrieb:
paul,
i use chunks of gum instead of the powdered, but the amounts should be
the same. it only takes longer to dissolve.
i make a 33% stock solution ( 100gr gum + 200ml of distilled water)
and i dilute it 1+1 for use (a ~16% solution). because i found that
the 33% solution gets sticky too quickly when painting on the
emulision. it starts drying, before i can even it out.
i don't use any preservative at all, but i keep the gum solution in
the fridge. this way it keeps at least for a few months (even when not
using distilled water, which i once did).
best wishes
phritz
Paul Viapiano schrieb:
Katharine...thanks, and btw...if I buy some DS powdered gum, how
should I mix it?
p
----- Original Message ----- From: "Katharine Thayer"
<kthayer@pacifier.com>
To: <alt-photo-process-l@usask.ca>
Sent: Tuesday, September 29, 2009 12:01 PM
Subject: Re: daniel smith gum
I looked up that previous discussion about how some gum arabic is
not acacia senegal but acacia seyal. It was a link to a Kremer
page supplied by Alberto Novo in January of this year that alerted
me to the difference between acacia senegal and acacia seyal, the
description of the brittleness of the dried acacia seyal making me
wonder if perhaps the Daniel Smith premium gum may be at least
partly acacia seyal.. I can't seem to find my way back to the
exact Kremer page to link it directly, but here's a post where
Alberto copied the relevant paragraph from the page:
http://www.usask.ca/lists/alt-photo-process-l/200901/msg00118.html
The fact that the Kremer price list at that time identified at
least one of their gum arabics as a mixture of acacia senegal and
acacia seyal, made me wonder even more whether Daniel Smith may
also mix these two types of acacia, but was unable to get an answer
to my question from Daniel Smith. Now the Kremer price list
specifies that their powdered gum arabic is either acacia senegal
OR acacia seyal, no way of knowing which one you're going to get.
The Daniel Smith premium gum does print very nicely, don't get me
wrong, that's why I've kept with it in spite of my issues with some
of its qualities, but it does have these odd qualities. My
suspicion that it may be at least partly if not wholly acacia seyal
instead of acacia senegal is just a speculation on my part, since I
couldn't get an answer from Daniel Smith, but it's definitely not
the same material as the other gums I've used. And I don't really
know whether the powdered gum will turn out to have the same
qualities as the liquid premium gum, but I'm hoping it won't. It
would be helpful if they were more fothcoming about what gum(s)
they are marketing under the product name "gum arabic."
Katharine
On Sep 27, 2009, at 9:45 PM, Katharine Thayer wrote:
Paul, like all answers in gum, "it depends"....
I don't care for the standard (dark) gum, mostly because I mix
pigment/gum mixes by eye and I need the color and darkness of the
gum not to obscure the color of the mixture. I also once believed
someone's assertion that the dark color of the darker gums
sullies the brightness of the colors in the finished print, but
when I tested that assertiont, it turned out not to be so. But I
did find that the darker gums,including the DS standard gum,
tended to print with fewer steps (more contrasty) than the lighter
gums.
I've been using the Daniel Smith premium gum exclusively for three-
four years now, and I have a couple of issues with it. The
pigment/ gum mixtures I make with it seem to quickly become more
viscous and before long, dry up altogether. This never happened
with the old Formulary gum; I have mixtures of little-used colors
made with it that I've had mixed for years and years, that are
just as fresh as the day I mixed them. Generally my mixes made
with this Daniel Smith premium gum are unusable within 6 months or
so. This is a problem.
The gum also has a different quality than what I consider quality
gum arabic, a brittleness that I saw when I brushed out
unpigmented gum on a piece of paper and let it dry. Normal gum
arabic, brushedout in a thin coat, dries smooth with a slight
gloss; the DS premium gum is brittle when dry, and cracks or
flakes (shatters, actually, is a better word to describe what it
looks like) into shiny bits like tiny pieces of cellophane that no
longer adhere to the paper. I've never seen this happen with the
pigment mixed in, only with the plain gum. I don't know what this
means, but a description I read somewhere of a slightly different
type of gum, (not acacia senegal but a different variety)
including that it's more brittle than acacia senegal, for example,
sounded so much like the behavior of this gum that I began to
suspect that this gum may be at least a mixture of acacia senegal
and this other type of gum. I don't remember the particulars,
like what variety of acacia this other gum is from, but I do
remember that I wrote a post or two about it at the time, which
should be found somewhere in the archives. I called Daniel Smith
and asked, but no one could (or would) tell me anything. They
make their own watercolor paint, and one might suppose that the
gum arabic that they sell would be the same as the gum arabic that
they use in their watercolor paint, and you would think that the
people who make the paint would be able to answer that question,
what variety of acacia their gum arabic comes from, but maybe they
consider it a trade secret or something. At any rate, I've
recently mixed up a batch of the gum they sell as powder, and
while I haven't actually printed with it yet, just mixing it and
working with it, feeling its character, it *feels* more like "gum"
to me. We'll see. I'm really quite tired of having to toss out
dried up cannisters of mixed gum/igment; it's a huge waste of pigment.
As to the Formulary, I don't know what they're selling now. I
used to love their gum but when they started selling something
resembling crankcase oil for their premium gum, I bailed out and
haven't bought gum from them since. But since gum, like wine,
changes from season to season, an observation made some time back
is essentially useless now.
Katharine
On Sep 25, 2009, at 3:36 PM, Paul Viapiano wrote:
Daniel Smith gum...standard or premium light?
Is there a big difference between the two and is it much
different than the Formulary gum?
Just curious...
Paul
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