Re: daniel smith gum
Well, I don't know that there's a definitive answer as to how one
"should" do anything in gum, but I mixed it using the proportions I'd
seen mentioned: 2cc water for every gram of powdered gum, whirled in
a blender and allowed to sit overnight to allow the foam to settle,
then poured into jars for storage. I have no way of testing whether
this corresponds to 14 Baume, but as I said, it feels like gum. The
package of powdered gum (I don't remember the weight of it) made a
solution that filled two of Daniel Smith's pint jars. I used thymol
(available from Formulary) as a preservative.
There's still a very real possibility (I'd guess >60% probabilty)
that this is the same gum as the premium gum; I'd have to mix up a
pigment/gum mix and leave it for several months before I know for sure.
katharine
On Sep 29, 2009, at 12:23 PM, Paul Viapiano wrote:
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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