Carl Weese (cjweese@wtco.net)
Tue, 11 May 1999 20:03:22 -0400
Eric Neilsen wrote:
>
> And as i noted Carl and Jeffrey, I see the water or humidity playing a big
> role. I may be way off there. I was going to run some test with ratios of
> traditional ferric and AFO to see if that might help.
Eric,
Humidity not only plays a big role, but the role it plays changes
dramatically with the paper choice. I suspect that careful control of
procedural matters like matching the humidity to the paper may be
significantly more important to overall quality and control than
chemical tweaking, though that may well prove a valuable tool as well.
Also, tests a year or so ago showed that replacing some AFO with
traditional ferric oxalate in a Ziatype acted as an intense contrasting
agent. Not an especially useful one though since it showed more tendency
to graining than ammonium dichromate, and the color change it gave to
Platinotype (Cranes 90# cover natural white) didn't strike me as
pleasant.
---Carl
This archive was generated by hypermail 2.0b3 on Thu Oct 28 1999 - 21:39:33