Re: re.gum bichromate

Virginia Boehm (gini@ix.netcom.com)
Wed, 28 Jun 1995 05:10:25 -0700

>
>I would imagine tri colour gums are a nightmare because after the
first
>coating, the paper has in effect had another coat of size. Stronger /
>weaker size also affects the adhesion of the emulsion, so does each
coating
>need different gum/pigment ratios?
>Why do we do this?
>
>Roy.

I start my tri-colors with a double coat of sizing, after shrinking the
paper as much as possible. While I mix the colors in the same pigment
to gum ratio, I've found out that the color one starts with does adhere
the best, so I start out with a less dominant color, so it doesn't get
lost in the subsequent layers. For example, if its a warm-tone subject
with blue primarily in the shadows, the blue will go on as the first
layer. Conversely, for a landscape with a lot of blues and greens,
the blue goes on last. Its all guess work (this mostly is, you know
only we call it "art" :-) )and this usually works pretty well.
Gini
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