Re: Blue gels and Pt contrast

Carl Weese (cjweese@wtco.net)
Thu, 19 Feb 1998 12:46:52 -0400

Dick,

<<<DuSel also says that blue
gel has no contrast effect on the Ziatype but does change its color. >>>

There seems to be a real correlation between light source (or filtration
or negative color/stain) and print emulsion response, in color as well
as contrast. My recent tests of pyro-developed negatives have shown that
Ziatype prints give different color response to these negatives. Zia
formula's that have just a touch of cesium and generally print just
slightly warmer than neutral print a good deal more brown when the
negative is a yellow/green pyro neg. Something about the color of the
light is changing the paper sensitivity, but I don't know what. It would
be intresting to see what other gel filters might do, strong yellow or
green ones--what effect on contrast, and what effect on print color?

---Carl