Re: When to tone?

----- Original Message -----
From: "Judy Seigel" <jseigel@panix.com>
To: <alt-photo-process-l@sask.usask.ca>
Sent: Friday, November 14, 2003 1:34 PM
Subject: Re: When to tone?

>
>
> On Fri, 14 Nov 2003 bobkiss@caribsurf.com wrote:
>
> > ... This seems to imply that one must
> > proceed with complete fixation AND complete washing
before drying even
> > if one intends to tone and give a subsequent complete
wash after
> > toning.
>
> Bob, everything I've read & heard, even down here at the
consumer level,
> says that once a print dries, any remaining fixer will be
> difficult/impossible to remove.
>
> J.

   The fixer can be removed but if fixing is not complete
the remaining halides and silver complexes will slowly
change to a form which can no longer be converted to soluble
form and washed out. This takes about two weeks.
   Remaining thiosulfate probably begins to cause some
sulfiding of the image pretty quickly. A controlled amount
of sulfiding protects the silver from further sulfiding or
from stains. However, if a lot of hypo is left in the
emulsion it will eventually cause both sulfiding and
staining of the image. Sometimes such images can be rescued
by a bleach and redevelop process but that always carries
the risk of destroying whatever is left.
  For conventional silver-gelatin films or prints the best
technique to get long life is to fix in two successive
fixing baths which are tested often to insure they are not
exhausted. Then treating in a sulfite wash aid (like Kodak
Hypo Clearing Agent) and washing according to instructions.
Adequate washing can be gotten with running water or with
successive baths but long soaks in still water should be
avoided. Its not an efficient method of washing plus it can
damage both emulsion and support (of paper). Excessive
washing can reduce stability toward oxidation. Following the
Kodak instructions for KHCA will get you prints with a very
long life. For greater protection against oxidation, which
is the main threat to images these days, the film or print
should be toned. Kodak Brown Toner is a suitable toner for
image protection. It tones all densities uniformly even when
only slight toning is done. Gold toning is also effective
but is expensive.
  Full toning in any sulfiding (sepia) toner, Kodak Rapid
Selenium Toner, combination toner (the late lamented
PolyToner or old Viradon) or a Gold toner, will result in
very permanent images.

---
Richard Knoppow
Los Angeles, CA, USA
dickburk@ix.netcom.com