Re: Carmen's carbon
Pollmeier Klaus (100561.2417@CompuServe.COM)
01 Nov 96 04:36:34 EST
Judy,
although I don't have a copy of the mail with the formula you are referring to,
I can hardly imagine that somewhere I recommended adding powdered dichromate to
a tissue emulsion. The only formula I have in my files (and from which I have
made copies) which uses dichromate during tissue manufacture to get a
presensitized tissue suggests 25 ml of a 5% pot. dichr. solution. Following the
instructions you get approx. 125 ml of pigmented and sensitized emulsion, so the
actual concentration in the final tissue is around 1%.
The formula in your mail
> 70 ml water
> 7 g gelatin (1 knox package)
> 3 g sugar (one of those individual packages)
> 8 g Rowney jet black guoache
> 6 g ammonium Dichromate.
is not of my origin. I, for example, don't know where to buy the Rowney jet
black gouache and have never seen knox gelatin here in Germany. Al Strauss, who
used my formula, reported good, or at least encouraging results after his very
first tests.
Klaus Pollmeier