Re: Tonal inversion (was (Gum) Tonal scale)

>>> tsobota@teleline.es 12/03/05 5:36 AM >>>
>>...
Have a look at this test strip, printed with lampblack (0.03g in 2cc
gum solution + 2cc Amm.Dichromate 30%, paper twice sized
with gelatine)
http://usuarios.arsystel.com/tksobota/Lampblack_strip.jpg
<<

Well raise my rent! There it is again. Thanks for the confirmation Tom
and Judy.

I'm wondering if it may also be some sort of heat effect since it
happens under dense areas of the negative? (Like, dense areas capture
and retain heat more at a certain opacity essentially cooking those
areas underneath and trapping some pigment in heat-hardened gum???)

Probably another good reason to keep gum negatives on the thin, low
contrast side, minimize exposures, and build density through several
layers rather than trying to do it one-shot.

Joe
Received on Sat Dec 3 10:21:49 2005