Re: daniel smith gum
Phritz...
Why not just make a 16% sol in the first place? Curious...
Paul
----- Original Message -----
From: "phritz phantom" <phritz-phantom@web.de>
To: <alt-photo-process-l@usask.ca>
Sent: Tuesday, September 29, 2009 1:10 PM
Subject: Re: daniel smith gum
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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