Archived posting to the Leica Users Group, 2003/04/03
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Subject:
[Leica] xtol replacement or i love xtol... when it works
Date:
Wed, 2 Apr 2003 23:34:34 -0800 (PST)
From:
Marty Deveney <sealpup@sharkattacks.com>
Reply-To:
leica-users@mejac.palo-alto.ca.us
To:
leica-users@mejac.palo-alto.ca.us
>
>
>
> Specks in Xtol can spell trouble, but often they don't. Phenidone is an excellent surfactant, but not very soluble in water. Ascorbates are soluble, but are not surfactants at all. More soluble developing agents exist, such as p-Phenylenediamine, but it is a slow, physical developing agent because it is _so_ water soluble (it acts as it soks into the emulsion rather than acting on the surface).
>
> When you dissolve Xtol and see little specks, it is usually undissolved phenidone (when it isn't, I am not sure what it is - with some tap water it is undoubtedly a precipitate from a chemical reaction you've started in the developer); if an insufficient amount has gone into solution, the developer does not act evenly over the surface of the hydrophobic emulsion and you can get spots.
>
> Mixing with distilled water at the upper end of the Kodak-preferred temperature range, helps, as does allowing the developer to sit overnight before use in a full, sealed bottle.
>
> Rodinal is okay, but the curve of most films developed in it usually shows a dip that equals slightly depressed mid-tones. If you decide not to use Xtol, I don't think Rodinal is a substitute.
>
><Snip>
>
Yes Marty I'm not sure you know that Xtol was invented with the first
perogitive being solubility. People not happy dissolving D76 so they
sent these people out with the mission of making something more
dissolvable. I'm not even sure the mentioned the quality of the
developer and which "class" it would be in.
The new type of Phenidone they used superadditivity action with the
Ascorbate they used turned out to be not old extremely soluble. But have
great properties as a developer namely high res with fine grain. A hard
to come by combination.
Beutlers would be a better so called replacement but it's a different
look. A different developer.
My Xtol disappears quickly at the lower temperatures.
By the way I have a strange rule.
I stir things 100 times and i count as i do it. (That's how i know it's
100 times) After that. That's it. I"m not going to drive myself crazy
with this stuff.
As you say all the funny stuff is gone in the morning but I've run tons
of film with "Rosebud" floating around and it all comes out
immaculately. You'd think they stuff "various developers" would stick to
the film and make marks but it just never does.
Beutlers is according to Anshel Troop a different CLASS of developer
than the ones with all the sulfite like D76 and Xtol and most MQ or PQ
developers. Beutlers uses almost no sulfite and is in the "sharpness"
glass. Maybe "extra sharpness". And there even may be an "ultra
sharpness" Not the "solvent" class. These names may vary I cant find my
book I'm renovating but the jest I think is there.
Distilled water would be the key as John Collier says we never found out
if this fella used that or not.
I'm lucky in Portland Oregon on my street the water is Xtol Friendly all
year round.
glug glug
Mark Rabiner
Portland, Oregon USA
http://www.rabinergroup.com
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