Re: gesso for watercolor?
phritz, Gamblin PVA is polyvinyl acetate, a light translucent gum-
looking liquid used mostly as a glue. Several people, motivated by
Jim's success using it as a sizing for gum, have taken it up; I
suspect I'm the only one who hasn't been pleased with it, so I
wouldn't weigh my observations too heavily.
Several people have used acrylic gesso (white ground usually used as
a ground for painting) as a size for gum. Gesso mixed with gelatin
is one of my favorite sizes for gum, as far as liking the way the
print looks, but I haven't used it much because it's messy and
because I've been unsure about archivality of the unusual mixture.
Recently Keith Gerling and Loris Medici traded observations about
gesso in various combinations as a sub for gum on wood and on
aluminum ; you should be able to find that thread in the recent archives
http://www.usask.ca/lists/alt-photo-process-l/
or maybe they'll chime in to answer here.
Katharine
On Mar 16, 2009, at 9:48 AM, phritz phantom wrote:
is this stuff the same as acrylic gesso/primer?
i've used acrylic before and the results were ugly: flaking, very
greyish... allover not pleasant. at all dilutions.also sometimes
the emulsion seems to go very deep into the size, so the prints
could really take a strong brushing without the emulsion coming
off. mixing it with gelatine helped a little, but still not as
good as pure gelatin or no size at all.
now (i still have almost a whole bucket of acrylic gesso left...a
500ml was the smallest size) i've found out that acrylic primer is
not suited fot watercolor pigments. i should read labels before
buying. but i found a gesso which is suited for watercolor, it's
lascaux gesso. but before i spend money on half a liter of stuff
that doesn't work either, has anyone ever tried this product?
here's a link to the datasheet:
http://www.lascaux.ch/pdf/en/produkte/malhilfen/impraeg_grund/
52305.02_grundierungen_.pdf
phritz
Katharine Thayer schrieb:
I don't know about pt/pd or other processes, but I've been trying
it for gum and so far not pleased with the results. Apparently I
don't have Jim's magic touch, or something. I believe Jim uses it
at full strength (if I have that wrong, please correct) but at
full strength I get a grainy image (will scan example later if I
remember to get it when I go downstairs) that isn't acceptable to
me; I also dislike the high shine. Have also tried it at half
strength and 1/3 strength but didn't like those either, I forget
now why. Would need to go down and look at test prints to refresh
my memory. All I know is, none of my experiments with Gamblin PVA
sizing for gum were satisfactory to me, and I've gone back to
gelatin and glyoxal. This was on Arches bright white, a very
hard, crisp-surfaced paper; I suspect it may work better on a
more absorbent paper.
Katharine
On Mar 16, 2009, at 9:05 AM, Paul Viapiano wrote:
Hi all...
What about using Gamblin PVA size?
I know that Jim Larimer likes to use it for gums...has anyone
else used it for pt/pd or other processes?
I'd like to buy a bottle today and try it out...
Paul
----- Original Message ----- From: "Alberto Novo"
<alt.list@albertonovo.it>
To: <alt-photo-process-l@usask.ca>
Sent: Monday, March 16, 2009 9:29 AM
Subject: Re: agar sizing
Damiano,
did you note if it still has adhesive power round 40° ?
8 - )
I think you mean if this happens after a warm soaking, like for
resinotype. I don't believe agar swells like gelatin, because
you need to rise the temperature up to 90°C to dissolve it.
However, I will check these days.
is it yellowish or it has other "nuances"?
I have a yellowish agar, given me by a biologist, and a
perfectly white (edible) agar bought in a grocery. But also the
yellowish one, once brushed on the paper and air dried, is only
barely visible but for the shine of the sheet.
Alberto