Archived posting to the Leica Users Group, 2006/01/18

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Subject: [Leica] st. Petersburg now film speed and Xtol derivatives
From: jblack at ambio.net (John Black)
Date: Wed Jan 18 10:49:25 2006
References: <2CD079F5961A2E4199FD0A177852A514498C11@sagemsg0024.sagemsmrd01.sa.gov.au>



<snip>
> I personally get the best results with TMZ, but I know different methods
and
> aesthetics like different things.

I use D3200 occasionally, but don't really like to because it grates on me
to have to grossly overdevelop a film.  Brings up all of the bad
characteristics like contrast, grain and fog. BTW, if you ruthlessly hold
the pH down to 8.3 or so, the 3200 films just can't be made to perform.  Any
shadow detail at all requires a pH of 8.7 or greater.

>
> Many of the Neopan 400 photos were developed in Xtol 1+3 with more
> s-dimezone and isoascorbate added, to bring the concentration of
developing
> agents to be the same as straight Xtol.

That's pretty much what I do except I use phenidone instead of dimezone-S.
The phenidone keeps fine if disolved along with the ascorbic acid in a
non-polar solvent such as one of the glycols (ethylene or propylene) or a
suitable anhydrous alcohol (methanol works fine).  Sulfite can be kept for a
year or more as a saturated solution (put 300gm in a liter of water and
stir, don't use until the next day) as long as it's kept in an air tight
glass bottle.  I even use the same formula with a carbonate buffer (pH 10.0)
as paper developer.


  I also added a small amount of
> hydroxide to bring the pH to the same as stock because the additional
> ascorbate made the solution too acidic and slowed it down to glacial pace
> (underdevelopment after 30 minutes).  I'd previously tried using more
> metaborate, but trials showed the results were the same with a freshly
mixed
> sodium hydroxide solution, which is cheaper.  I also needed less.

You don't even have to use metaborate (Kodalk) if you don't want to. Simple
borax from the supermarket when used with sodium hydroxide works fine and is
really cheap.

  I got
> this idea from formulae 2-5 in the Xtol patent US Patent 5 853 964.
That's
> here: http://tinyurl.com/7sqrj

That and Gainer's articles in the magazine press inspired me. But I think
Kodak's present formula for Xtol is not exactly like the patent disclosure
because it behaves differently.  BTW, ever notice that Xtol's pH goes up
when you dilute it?  Undiluted it is 8.2-8.3, but at 1+4 it is 8.5.  This is
a fairly well described property of borate buffers and explains the residual
activity of this product with dilution.  If you hold the pH to 8.2-8.3 and
drop the PC concentration to 50/3/L (1+3 Xtol) it is too weak.

>
> It's basically straight Xtol with the sulfite of 1+3.  I call it 'Xtol
> Plus'.  The developing times are about the same as straight Xtol but as
> always, test.  In commercial settings, the developing times are probably
> important.  I can't tell the difference between 12x16" prints from the
> original 1+3 developer and the variant.  If anything, there may be
slightly
> greater overall contrast and slightly lower local contrast (Less than 0.1
> CI) in the negs from 'Xtol Plus'.

I can't tell Xtol 1+3 negatives from my homemade JB9 formula either.  My
developer is made from liquid concentrates that are stable for at least a
year so I don't have to buy Xtol in 5L packages and worry about "sudden
death" which I have seen at least once in the last 5 years (ruined 4 rolls
of film).
>
> I would have used PC-TEA, but the only source of triethanolamine I can
find
> in Australia is very expensive because the product is AR grade.

TEA is interesting stuff but has a couple of drawbacks as far as I am
concerned:  It is very viscous (about like honey) and hard to measure. As a
buffer, it's pKa is too far from optimum (poor buffer @ 8.3). I chose Tris
because it has a pKa of 8.2 and was cheap and plentiful (up here). You must
follow Gainer or Suzuki's reccomendations.

JB



In reply to: Message from deveney.marty at saugov.sa.gov.au (Deveney, Marty (PIRSA)) ([Leica] st. Petersburg now film speed and Xtol derivatives)