[rollei_list] Re: XTOL Mix-It-Yourself Formula
- From: "Richard Knoppow" <dickburk@xxxxxxxxxxxxx>
- To: <rollei_list@xxxxxxxxxxxxx>
- Date: Tue, 27 Jul 2010 11:46:57 -0700
----- Original Message -----
From: "Marc James Small" <marcsmall@xxxxxxxxxxx>
To: <rollei_list@xxxxxxxxxxxxx>
Sent: Tuesday, July 27, 2010 9:11 AM
Subject: [rollei_list] Re: XTOL Mix-It-Yourself Formula
At 04:24 AM 7/27/2010, Richard Knoppow wrote:
> Kodak stopped selling the one liter size because
they
>could not seal it correctly and too many of them arrived
>with the Phenidone oxidized and dead.
Richard
Please pay attention. The 5 Liter size is simply
unusable by a small-volume home processor. And
as commercial labs do not favor XTOL, it is no
wonder that the product is not selling. If the
sealing of the 1 Liter package was a problem,
then the obvious solution was to develop better
packaging, not to render the product unsalable by
putting it out in a huge quantity. Even a 3
Liter bag might have worked, but not 5 Liters,
especially in the US, where home processors are
pretty tightly wedded to the quart/liter size,
or, at the most, 1 gallon. 5 Liters is 1 1/3
gallons, for Pete's sake, an impossible quantity.
There is a substitute formula based on orange
juice which apparently matches XTOL's performance
quite closely, and that is the formula I am
attempting to find. The alternatives suggested
to date all use exotic chemistry which would
require me to set up an account with Fisher Scientific.
Marc
The five liter size is NOT unusable by the home
processor. Its easy to split it up into one liter
containers. If you use developer one-shot the stock will
last long enough. I generally mix D-76 in gallon size. I am
not a high volume user. 5 liter containers are available
from Freestyle and others.
Orange juice has some ascorbic acid in it as do other
citrus juices. Ascorbic acid is Vitamin-C. However, its
there in relatively small quantity and with a _lot_ of
impurities. Ascorbic acid and Sodium ascorbate is readily
available so there is no purpose in makeshifting.
I think you can get all the ingredients for the powder
formula given in the Xtol patents from Photographer's
Formulary. Keep in mind that the patent formulas are
examples meant for commercial production and packaging. Some
simplification may be possible for a mix from scratch batch
especially if you use boiled or distilled water and don't
need the sequestering agents.
It has also been speculated that the EDTA in the formula
may accelerate the "sudden death" syndrome. Not proven.
I wrote Ryuji Suzuki and he responded that pH
measurements can be made on photographic solutions with
_narrow range_ pH test papers but not wide range ones which
have neither the accuracy or precision required. He also
confirmed to me that all pH electrodes are rapidly attacked
by photographic solutions and have short lives. That means
that the cheap pH meters that have non-replaceable
electrodes are essentially useless. The better ones ($300 to
$500) have replaceable electrodes and are suitable but the
electrodes must be considered expendable.
--
Richard Knoppow
Los Angeles, CA, USA
dickburk@xxxxxxxxxxxxx
---
Rollei List
- Post to rollei_list@xxxxxxxxxxxxx
- Subscribe at rollei_list-request@xxxxxxxxxxxxx with 'subscribe'
in the subject field OR by logging into www.freelists.org
- Unsubscribe at rollei_list-request@xxxxxxxxxxxxx with
'unsubscribe' in the subject field OR by logging into www.freelists.org
- Online, searchable archives are available at
//www.freelists.org/archives/rollei_list
Other related posts:
