Ilford Wash Procedue

"Lloyd Erlick" Lloyd at @the-wire. dot com wrote in
message ...
June 20, 2007, from Lloyd Erlick,

I've been operating my darkroom without acid
for years now, and I find Richard's comments
(below) absolutely accurate. In fact, his
first paragraph is essential.

I have to add something important, though --
the incredible ease and simplicity of it all.
Plain fixer is easy and quick to make up,
rinsing in tap water is a lot easier than
preparing acid stop, never mind smelling it.

Shorter wash time requirements from non-acid
fix, coupled with sulfite washaid, can very
easily result in rigourously correct,
'archival' prints. It's just easier and less
effort without acid.

My hatred of sulfur dioxide and hydrogen
sulfide made my decision!

regards,
--le
________________________________
Lloyd Erlick Portraits, Toronto.
website: www.heylloyd.com
telephone: 416-686-0326
email:
________________________________

The evolved gas is important. If you are sensitive to
Sulfur dioxide that can be enough to justify using an all
neutral process. The problem is that acid fixing baths
constantly emmit a small amount of Sulfur dioxide. Some
people are very sensitive to this gas which can set off
Asthmatic attacks and cause a choking sensation even in
those without asthma. Hydrogen sulfide is the gas with the
rotten-egg odor. It can result from fixing baths which are
nearing exhaustion but is not usual. It is more often
encountered when using certain kinds of sulfiding toners.
Any solution which emmits Hydrogen sulfide should be used in
a very well ventillated place, even outdoors and should be
kept away from unprocessed sensitive materials because the
gas is a prolific fogging agent.
A non-hardening fixing bath can still be acid but can be
less so than a hardening bath. The acid condition of the
hardening bath must be right for the hardener to work.
Without the hardener the fixer can be just acid enough to
inactivate carried over developer. Low acid fixer is much
less likely to produce irritating gasses.


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Richard Knoppow
Los Angeles, CA, USA

On Mon, 18 Jun 2007 14:13:19 GMT, "Nicholas
O. Lindan" wrote:

I don't know why Permawash should be innefective

It appears to contain 1/2 the amount of sulfites,



June 24, 2007, from Lloyd Erlick,

Maybe PW mixed at twice the recommended
concentration??

I've always just used a two percent solution
of sodium sulfite.

regards,
--le
________________________________
Lloyd Erlick Portraits, Toronto.
website: www.heylloyd.com
telephone: 416-686-0326
email:
________________________________
--

On Jun 24, 10:32 am, Lloyd Erlick wrote:

I've always just used a two percent solution
of sodium sulfite.


And I've been plugging Agfa's recommended
sodium carbonate. What happened? Dan

wrote in message
ups.com...
On Jun 24, 10:32 am, Lloyd Erlick wrote:

I've always just used a two percent solution
of sodium sulfite.


And I've been plugging Agfa's recommended
sodium carbonate. What happened? Dan

This is a pretty old thread now but I will add a bit
anyway. The Agfa recommendation is based on work done in its
labs in the 1930's. Its well known that treating film in a
mild alkaline bath will increase washing rate especially
when its been fixed in an acid fixing bath. As I stated in a
previous reply the pH change affects the electric charges in
the gelatin so that they do not attract the Thiosulfate ions
but rather repel them. It also breaks the bond caused by
Aluminum sulfate hardener, however, it also destroys the
hardening effect. A plain alkaline bath, however, does not
have the ion-exchange properties of Sodium Sulfite. It is
this ion exchange effect which causes Sulfite to have such a
strong accelerating effect on washing. Of course, sulfite is
also mildly alkaline. The buffering to neutral pH in Kodak
Hypo Clearing Agent is about optimum for washing because it
eliminates the bonding caused by aluminum hardener without
destroying the hardening action.
While Agfa recommends 2% Carbonate nearly any mild
alkali, such as 2% Borax, will do if one wants only the pH
adjustment. However none will be as effective as the Sulfite
bath.


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Richard Knoppow
Los Angeles, CA, USA