From: Dave Rose (cactuscowboy@attbi.com)
Date: 02/24/03-09:49:49 PM Z
I'm using powdered pigments at ratios ranging from 1g/10 ml gum with Old
Holland Yellow Ochre Burnt to 1g/130 ml gum with Winsor Newton Winsor Blue
(phthalocyanine). Quinacridone can be weak or strong, depending on the
source. For example, I use Winsor Newton Permanent Rose at 1g/10 ml while I
mix Block X Magenta at 1g/125 ml. Both are "quinacridone" according to the
manufacturers. It varies so much from one source to the next. In case
anyone's wondering, Block X Magenta is too biased towards blue to be a good
choice for 3 color or 4 color printing.
Dave in Wyoming
----- Original Message -----
From: "Christina Z. Anderson" <zphoto@montana.net>
To: <alt-photo-process-l@sask.usask.ca>
Sent: Monday, February 24, 2003 6:48 PM
Subject: Re: gum printing
> Dave, Katherine, and now 17 others I have counted!
> Dave, what amount of powdered pigment do you use in your gum? I see
> most measures have 1/2-6g of tube paint per 12 ml of gum arabic; since the
> powder doesn't have fillers, you must use way less, huh? I have a bunch
of
> powdered pigments and then tons of watercolors, so I thought I'd try both.
> Also have some nice powdered golds that were an absolute bust when used in
> liquid emulsion--probably will be in gum, too.
> Quinacridones are not weak, they are seriously strong, which is why I
> like them--the corals and siennas are gorgeous. I'm lucky in that I have
> all the paints anyway so I could try all kinds. This is what I found: if
> you want a brilliant chartreuse, use Daniel Smith green gold. With more
> exposure, the more chartreusey it gets. I got the most garish but fun
Pisa
> with the green gold base and quinacridone violet on top--pretty trippy,
not
> for the faint of heart. Successful 2 coats for me were quinacridone
sienna
> and q. violet on top, q burnt orange and payne's grey, among others. Then
> D. Smith has a real 50's blue/green called cobalt teal blue, and I would
use
> that with moonglow on top. But moonglow would bleed all the time, so I
must
> not have exposed it enough.
> I just got done reading thru Livick's book, and only have 3 more to
> research thru--Farber, James, and Crawford, til I'm done the reading part
of
> my research and onto the testing part (so far have condensed it into
11pp).
> I am quite excited. I've come across such wonderful notes, such as
Heidi's
> starch size, the discussion a while back of chromium vs. dichromate stain,
> and Katherine, I'm glad you cleared up the sulfuric acid point. I've got
> some paper sized with brush on alum as per Sandy King, spray starch as per
> Hirsch (I heard it yellows) and cannot believe that Livick actually
brushes
> his sizing on, too. That'd save a heck of a lot of time.
> I also notice Livick uses a 1% pot metabi clear, because it doesn't
> soften the gum like sod bisulfite, which is what you, Katherine, said a
> while back. I am also really interested that Livick feels you should be
> getting a perfectly deep print in two coats or you aren't mixing your
> ratios/exposing correctly. We were taught more or less that the more
coats
> on the better. I suppose both are opposites and there is a happy medium.
I
> will also try Judy's one coat delicious gum with unsized Buxton...
> More, later.
> chris
>
> > Greetings from Big Wonderful Wyoming,
> > Most of the pigments I use are bought in powder form. Carbon Black from
> > Photographers Formulary is a favorite. Ivory or Bone Black is weaker
and
> > warmer, but works well. I use the earth pigments a lot, Umbers and
> Siennas,
> > Indian Red, etc... They're an excellent choice for any gum printer.
> > Quinacridone is beautiful but weak, as you've noted. Cadmium reds and
> > yellows are effective but tend to be more opaque. Phthalocyanine blue
and
> > green are excellent - great covering power and intense color. I've also
> had
> > great results with Cobalt blue (cobalt aluminate). I've never used
white.
>
>
>
>
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