[pure-silver] Re: Yellow edges
- From: "Dave Valvo" <dvalvo@xxxxxxxxxxxxxxxx>
- To: <pure-silver@xxxxxxxxxxxxx>
- Date: Wed, 25 May 2005 20:58:28 -0400
To leach out all the ionic silver that may have migrated into the baryta
layer.
Silver can't migrate with resin.
Dave
----- Original Message -----
From: "DarkroomMagic" <info@xxxxxxxxxxxxxxxx>
To: "PureSilverNew" <pure-silver@xxxxxxxxxxxxx>
Sent: Wednesday, May 25, 2005 8:10 PM
Subject: [pure-silver] Re: Yellow edges
> Agfa, Ilford and Kodak literature indicate FB fixing times to be between
2x
> and 3x that of RC fixing times. Why do you think that is?
>
>
>
>
>
> Regards
>
>
>
> Ralph W. Lambrecht
>
>
>
>
>
>
>
> On 2005-05-26 00:09, "Richard Knoppow" <dickburk@xxxxxxxxxxxxx> wrote:
>
> >
> > ----- Original Message -----
> > From: "Ryuji Suzuki" <rs@xxxxxxxxxxxxxxx>
> > To: <pure-silver@xxxxxxxxxxxxx>
> > Sent: Wednesday, May 25, 2005 9:59 AM
> > Subject: [pure-silver] Re: Yellow edges
> >
> >
> >> From: "Richard Knoppow" <dickburk@xxxxxxxxxxxxx>
> >> Subject: [pure-silver] Re: Yellow edges
> >> Date: Mon, 23 May 2005 16:46:37 -0700
> >>
> >>> This is a better test than any test of the hypo itself
> >>> because it
> >>> shows if the hypo is working.
> >>
> >> That's an overstatement. Iodide precipitation test has its
> >> own
> >> advantage of being able to test the fixer solution at the
> >> beginning of
> >> each shift in roomlight, or without spending a lot of time
> >> to produce
> >> questionably fixed prints just for testing. The result of
> >> standard
> >> iodide precipitation test is conservative enough so that
> >> given enough
> >> fixing time prints are most likely fixed well enough not
> >> to cause
> >> positive results with sulfide or any other toner. I would
> >> rather
> >> recommend to spend same effort in more productive way, by
> >> toning all
> >> important prints. (and this may require to adjust printing
> >> to obtain
> >> the desired effect after toning.)
> >>
> >>> RC papers generally have thin emulsions so they fix
> >>> and
> >>> wash very rapidly.
> >>
> >> That's not the reason RC washes rapidly. Although some
> >> manufacturers
> >> use slightly different emulsions on RC and FB in the same
> >> product
> >> line, the fixing times are generally comparable and I
> >> don't see a
> >> general trend for the relation of emulsion "thickness"
> >> between
> >> different supports.
> >>
> >
> > Yes, a mis-statement and I realized it after sending
> > this. I know that any differences in fixing time between RC
> > and fiber paper are due to different emulsions. All paper
> > emulsions are thin since light must pass through them twice.
> > My understanding is that fiber paper fixes out in about the
> > same time as RC.
> >
> > As far as the Iodide precipition test, the iodide
> > precipition test needs to be done with some understanding of
> > the amount of dissolved silver it will indicate. If done
> > correctly, it will show partially exhausted fixer before it
> > stops fixing adequately. However, IMO, it can also be
> > misleading. The stain test is positive. It can be done with
> > a scrap of paper processed with the run of prints. If it
> > indicates inadequate fixing its possible to re-fix the batch
> > in a fresh fixer bath. Both tests have their places.
> > BTW, do you have any literature on the quantitive.
> >
> > Another note on fixing times. Old handbooks often give
> > very long times for fixing, on the order of 15 or 20 minutes
> > for both film and paper. I think there are two reasons for
> > this. One was to try to insure complete fixing where
> > slopping processing practice was used. That is, many prints
> > in a tray with inadequate agitation and, perhaps, partially
> > exhausted fixer. The other reason is perhaps more obscure:
> > it is to insure complete _hardening_. Sometimes the hardener
> > took longer to work than the fixer took to fix.
> > I rather wonder how much other "conventional"
> > recommendations were based on trying to overcome expected
> > poor practice.
> >
> > ---
> > Richard Knoppow
> > Los Angeles, CA, USA
> > dickburk@xxxxxxxxxxxxx
> >
> >
> >
> >
> >
> >
> >
============================================================================
==
> > ===============================
> > To unsubscribe from this list, go to www.freelists.org and logon to your
> > account (the same e-mail address and password you set-up when you
subscribed,)
> > and unsubscribe from there.
>
>
>
============================================================================
=================================
> To unsubscribe from this list, go to www.freelists.org and logon to your
account (the same e-mail address and password you set-up when you
subscribed,) and unsubscribe from there.
>
=============================================================================================================
To unsubscribe from this list, go to www.freelists.org and logon to your
account (the same e-mail address and password you set-up when you subscribed,)
and unsubscribe from there.
Other related posts:
