From: Dave Rose (photo@wir.net)
Date: 02/03/01-10:24:50 AM Z
Hello Dave S. and fellow gumprinters,
Most of my gum prints (Rives BFK paper) are made from either 11x14" or
16x20" negatives. Prints of this size will fluctuate (in the long
dimension) by as much as 1/4", with changes in relative humidity. Use of
registration pins holds accurate registration on one side of the image, but
more often than not, I have to either shrink or expand the print slightly
(with heat or moisture) to 'fine-tune' overall negative/print
re-registration. Knowing that I'll likely have to treat prints in this
manner, I make no changes whatsoever to sizing or the emulsion strength,
because I've never seen the need to. (My sizing is a one-time treatment
prior to first printing - two soakings in Knox gelatin & one application of
Formaldehyde). I've had problems with staining on occasion, but I can't
directly link it to the heat or moisture treatment. For me, staining occurs
more frequently with the third, fourth, or fifth etc.... printing. I think
staining is caused by a breakdown of the sizing and use of certain pigments
more than anything else.
Best regards,
Dave Rose AKA Cactus Cowboy
Big Wonderful Wyoming
----- Original Message -----
From: <FotoDave@aol.com>
(Dave R. wrote)
> << Now the trick is to either 'shrink' or
> 'expand' the print until registration is perfect. Use a hairdryer against
> the back of the print to shrink it. Use a barely damp sponge to moisten
the
> back side of the print if it needs expansion. Once the printed
registration
> dots match the holes in the negative, throw it in the vacuum frame and
make
> the exposure.
(Dave S. wrote)
> I tried something similar to what you described once. I dampened the back
slightly so that the paper would flatten. This was gum print, by the way,
but I got horrible result. The second coat stained terribly.
>
> I never tried it again, but now rethinking about it after seeing your
description, it sounds like the staining might have been caused by poor
sizing rather than the dampening.
>
> I will try it again. Did you have to do anything different (like adjusting
your emulsion strength or sizing the paper differently) when you used
dampening?
This archive was generated by hypermail 2b30 : 03/06/01-04:55:37 PM Z CST