Re: Help with gum pritns on black paper with white Gouache.

Good morning, list and Katharine,

     It is FRIGID here--meaning 23 degrees. Am I spoiled or what? I used
to live in MN, where it was frequently 30 below...
     Anyway, to the subject of gum on dark paper:

<snip from Katharine>
"What I think you're talking about, on the
other hand, is a form of drydown effect, which tends to be pronounced
with white watercolor paints; they lose significant opacity on drying,
but this is not nearly so true of gouache. (I'm assuming that when you
mentioned adding titanium white to colors to make them more opaque for
printing light over dark, you meant titanium white watercolor paint, not
gouache). "

     I say Yup. But losing opacity is not only with white paints, it is with
all paints. For instance, printing a layer of transparent magenta over a
cyanotype base, the magenta in the water looks milky and lighter over the
darks, but upon drydown gets transparent. Yellow looks positively yukky.This
opacity/loss of opacity appears different on the darks than it does on white
paper.

<snip from Katharine> "I printed the thing unsized, and then I sized a piece
of the paper with acrylic medium and printed that with the same gouache
mixture. As I expected, the sizing held the image above the surface instead
of sinking
in, but the resulting image had no midtones."

     I say this stands to reason, since contrast is always said to go up
with
sizing.

<snip from Katharine> "In neither case was drydown a factor in the loss of
midtones: in the case of the print on unsized paper, the gum image was fully
tonal but sank into the paper."

     I say my image, too, was fully tonal before it dried and the delicate
midtones disappeared and left only the shadows showing. It was a function of
their being too delicate I would suppose--opacity re: above.

<snip from Katharine> "I don't believe it's not possible to get a tonal
image with gouache, or with light over dark;" and "None of this helps
Carmen very much with her question: can gouache be printed on black with
continuous tone? I believe the answer is yes, but I can't prove it this
minute."

     I made no assertion that it is not possible to get a tonal image with
gouache, nor with light over dark, just that it is more putzy. I ended my
post with the fact that there must be a way to do it and maybe Carmen will
figure it out. It looks like Judy's students did, from PF 1.

     I did say, "If you could do enough layers to finally build up an image
on the dark background, maybe that would work, too. It did not for me,
though. The
white of the paper base really contributes more than we may think to give
the look of a tonal range." I still agree with this statement.
     I don't believe the lack of Carmen's midtones is due so much to paper
absorbency (this, on white paper, contributes to more midtones, if you think
about it) or sizing but a function of light over dark, and I wonder if the
lack of opacity of gouache would factor in when many layers are used.
     BTW, I did used to print with gouache, as there were some **gorgeous**
hot pink, purple, and orange colors I liked. Then someone questioned their
archivalness so I quit.
Chris
Received on Tue Jan 18 10:09:52 2005