[pure-silver] Re: WORKING OR STOCK? Darkroom Chemistry... Question
- From: `Richard Knoppow <dickburk@xxxxxxxxxxxxx>
- To: pure-silver@xxxxxxxxxxxxx
- Date: Tue, 03 Mar 2015 22:50:21 -0800
On 3/3/2015 1:04 PM, Brian Smith (Redacted sender smithcbrian2@xxxxxxxxx
for DMARC) wrote:
Thanks Richard for you very informative reply on fixers. Given that I
don't use a hardening agent (and ignoring any minerals in the wash
water), could I omit the EDTA from HCA without affecting its pH?
Regards - Brian
I don't think the sequestering agents have much effect on the
pH. They are mainly meant to prevent sludging from aluminum compounds
from the fixer and probably magnesium from the wash water. I think they
are also added so that the wash aid can be reused. I generally use it
one-shot. I posted the citations to Kodak's technical papers and the
patent long ago but would have to search through my records to find
them. BTW, Kodak did an enormous amount of research on fixing and
washing. Much of this stuff was published in more than one place, often
the Journal of the Society of Motion Picture Engineers. When the labs
were created in 1912 Meese and associates decided that their scientific
and technical papers should be published in established peer-reviewed
journals rather than in a house organ. This gave Kodak's papers an
immediate prestige they would not otherwise have had.
--
Richard Knoppow
dickburk@xxxxxxxxxxxxx
WB6KBL
Other related posts:
