Re: Coating for carbon

Sandy King (sanking@hubcap.clemson.edu)
Tue, 22 Oct 1996 00:25:51 -0400

Al wrote:

>Thats exactly what I found. Which means that when poured, the wet gelatin
>can be under 1 mm in thickness. You are right that heavier can't hurt. You
>just end up leaving more on the tissue after transfer, which gets thrown away.
>But this is of importance from a financial standpoint, especially if using
>tube watercolors for pigment.
>
Guys, I got to tell you that the question of tissue thickeness is a lot
more interesting than you are letting on. The amount of pigment in the
gelatin,combined with the quanity of pigmented used to coat a specific
area, has a very important relationship on, a) image contrast, and b)
relief characteristics of the final image. To understand this, draw a cross
section of two pigment tissue, one very thick and lightly pigmented,
another thin and highly pigmented, and run through your mind what will
happen with these two tissues, given an equal strength dichromate
sensitizer, and the same exposure to light.

Sandy