From: Katharine Thayer (kthayer@pacifier.com)
Date: 09/02/03-02:50:27 AM Z
Dave Rose wrote:
>
> The "caramel-brown color" evident in your prints could caused by: dichromate
> stain, pigment stain, overexposure, poor or nonexistent sizing, fogging by
> excessive ambient light while the coated paper is drying.... or a
> combination of the above problems. With proper exposure and development,
> you should get clean whites in unexposed areas.
Hi Dave,
Gary was using dichromated gum (unpigmented) for a size, and that's when
he got the brown, when he was exposing the gum in the sun to harden it.
No pigment, no negative. I don't think there's any doubt that it's
dichromate stain that's the problem, since there's no pigment involved,
and that the stain is due to overexposure. But since he was exposing it
in the sun, I think it would probably be hard not to overexpose it
enough to get brown.
Gary, did you put glass over the sized paper while hardening it? That
would help cut down the UV and increase the likelihood that you could
harden the gum without the brown. Also, I'd try cutting down the
exposure time if you haven't done that already.
I've never used hardened gum for a size and can't say how well it
performs as a size, but it seems to me gelatin is less bother all told.
Katharine
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