water treatments (was Re: Agyrotype)
Whether it is adequate for argyrotype or not is a completely
different matter, but leaving water overnight, boiling and
Brita filter are insufficient to completely remove chlorine
compounds in the water. Chemicals that remove chlorine from
water for fish tank react with silver and it just adds another
Solid carbon filter does reduce chlorine compounds, but even
the top performers made for home use is insifficient to remove
it completely. (You will still see cloudiness when dissolving
silver nitrate, while you see completely clear solution with
Properly treated tap water usually contains 0 or 1 E. coli
counts per liter of water. However, if you leave the water
out, as the chlorinating compound is slowly lost, the
bacterial count goes up.
Modern water treatment facility uses multiple methods to kill
bacteria (e.g., ozone treatment and chlorination), and this
allowed to reduce the amount of chlorinating compounds,
compared to decades ago. In case of Boston municipal tap
water, there isn't much that can be removed by average home
carbon filter. However, negative image of drinking tap water
seems pretty persistent and NPR programs occasionally report
dining establishments using filtered tap water to save carbon
footprint (e.g., a restaurant in San Francisco and the
employee cafeteria of google.). I do dinner parties fairly
often and I used to comment on this when I describe the menu
to the guest, with a pitcher of filtered tap water on the
table right next to bottles of fine wine, but these days
everyone knows that in my city (where people don't own a TV
and listen to NPR). Only thing I miss sometimes is the high
hardness of some mineral water. I wish someone sold tablets of
calcium and magnesium carbonates, USP grade, to keep in the
pitcher to add some hardness.
Anyway, if you want clear solution of silver nitrate, use
deionized water or triple or double distilled water. How much
that cloudiness affects the image quality is a separate
question for which I do not have answer. In case of silver
gelatin emulsion making, it does make difference.
"The truth that I am seeking is in your missing file."
(Bob Dylan, Something's Burning Baby, 1985)
From: Don Bryant <email@example.com>
Date: Tue, 27 May 2008 13:51:45 -0400
> Hi Folks,
> Anyone out there doing Argyrotypes?
> If so how do you deal with the requirement of non-chlorinated water for
> processing? This requirement is really putting a damper on my working with
> the process.
> Don Bryant