From: sreenath on
Hi,

I am using a rapid fixer sold in India be the name "Agefix"
The instructions that come with the bottle just suggests a dilution of
3-5 times for film.

I have been using the suggested dilution with no problem.

My question is the capacity of this diluted fixer. I kept using the 1
liter for more than a year. Every time I do a film clip test and
observe that film clears very quickly.

Is it possible for the fixer to clear the film clipping but still be
unable to fix the film completely?

Are there any other tests for fixers?

thanks,
Sreenath
From: Peter on
On Apr 4, 6:29 am, sreenath <sreenat...(a)rocketmail.com> wrote:
> Hi,
>
> I am using a rapid fixer sold in India be the name "Agefix"
> The instructions that come with the bottle just suggests a dilution of
> 3-5 times for film.
>
> I have been using the suggested dilution with no problem.
>
> My question is the capacity of this diluted fixer. I kept using the 1
> liter for more than a year. Every time I do a film clip test and
> observe that film clears very quickly.
>
> Is it possible for the fixer to clear the film clipping but still be
> unable to fix the film completely?
>
> Are there any other tests for fixers?
>
> thanks,
> Sreenath

I am not sure what Agefix is. If it is the Agfa liquid fixer, then
you achieve a rapid fixer by not diluting it so much. I used it for
years and found it convenient.

Kodak, in its book of formulas, has the formula for a simple test for
fixer. My copies of that book are currently in storage. If I am near
there I'll look for it.

The idea of the test is simple. You make a standard solution with
AgNO3 and put a specific number of drops of the solution in a specific
number of mililiters of fixer. If the fixer is getting weak, you will
not some white precipitate form or possibly only a very slight
milkiness. If the fixer is still good enough stirring or shaking the
mixture will cause it to clear. If it does not, it is used up.

Kodak also has a tech tip that sounds a whole lot more complex:
http://graphics.kodak.com/docimaging/uploadedFiles/techTip59.pdf

It may be that the difference is that some places Silver Nitrate is
hard to find.

My suspicion when using such a test is that running fixer to the
bitter end may leave a bit of either unfixed residue or silver
complexes with the thiosulfates. Consequently, I like to use a 2-bath
process where I do most of the fixing with the first bath and then let
it fix in a second bath. The second bath is not depleted very much
and I am happy to use the first bath until it fails to pass the test.
Thereafter I discard the first bath, promote the second bath to the
first bath and make a fresh second bath.

If I find my formalas, I will augment this, or perhaps someone else
will.
From: Stefan Patric on
On Sun, 04 Apr 2010 03:29:41 -0700, sreenath wrote:

> Hi,
>
> I am using a rapid fixer sold in India be the name "Agefix" The
> instructions that come with the bottle just suggests a dilution of 3-5
> times for film.
>
> I have been using the suggested dilution with no problem.
>
> My question is the capacity of this diluted fixer. I kept using the 1
> liter for more than a year. Every time I do a film clip test and observe
> that film clears very quickly.
>
> Is it possible for the fixer to clear the film clipping but still be
> unable to fix the film completely?
>
> Are there any other tests for fixers?

Agefix is an Agfa product. With standard dilution, no replenishment, 1
liter will fix 1 square meter of film before the fixer is exhausted.
That's about 20 rolls of 36 exposure, 35mm film.

Here's a link to the Agfa film chemistry pdf. The Agefix info is on page
12 of the document.

http://www.cri.ensmp.fr/~silber/photo/docs/films.pdf


Stef
From: Claudio Bonavolta on
On 4 avr, 12:29, sreenath <sreenat...(a)rocketmail.com> wrote:
> Hi,
>
> I am using a rapid fixer sold in India be the name "Agefix"
> The instructions that come with the bottle just suggests a dilution of
> 3-5 times for film.
>
> I have been using the suggested dilution with no problem.
>
> My question is the capacity of this diluted fixer. I kept using the 1
> liter for more than a year. Every time I do a film clip test and
> observe that film clears very quickly.
>
> Is it possible for the fixer to clear the film clipping but still be
> unable to fix the film completely?
>
> Are there any other tests for fixers?
>
> thanks,
> Sreenath

For films, a quick method is to discard the fixer once the clearing
time doubles compared to fresh fixer in same conditions (film type,
dilution, temperature, ...).

Otherwise, you have the potassium iodide test, described in Kodak
publication J-1 (page 40):
http://www.bonavolta.ch/hobby/files/Kodak%20j-1.pdf
There is a mismatch in that page where some blocks of text do not
follow each other properly.


Claudio Bonavolta
http://www.bonavolta.ch
From: Richard Knoppow on

"Stefan Patric" <not(a)this.address.com> wrote in message
news:Hd5un.57294$y13.23103(a)newsfe12.iad...
> On Sun, 04 Apr 2010 03:29:41 -0700, sreenath wrote:
>
>> Hi,
>>
>> I am using a rapid fixer sold in India be the name
>> "Agefix" The
>> instructions that come with the bottle just suggests a
>> dilution of 3-5
>> times for film.
>>
>> I have been using the suggested dilution with no problem.
>>
>> My question is the capacity of this diluted fixer. I kept
>> using the 1
>> liter for more than a year. Every time I do a film clip
>> test and observe
>> that film clears very quickly.
>>
>> Is it possible for the fixer to clear the film clipping
>> but still be
>> unable to fix the film completely?
>>
>> Are there any other tests for fixers?
>
> Agefix is an Agfa product. With standard dilution, no
> replenishment, 1
> liter will fix 1 square meter of film before the fixer is
> exhausted.
> That's about 20 rolls of 36 exposure, 35mm film.
>
> Here's a link to the Agfa film chemistry pdf. The Agefix
> info is on page
> 12 of the document.
>
> http://www.cri.ensmp.fr/~silber/photo/docs/films.pdf
>
>
> Stef

The real test for fixer is the residual silver in the
emulsion. There are two simple tests. One is about a 2%
solution of sodium sulfide (not sulfite) the other is a 1:9
dilution of Kodak Rapid Selenium Toner. Either will tone the
remaining halides or silver complexes readily leaving a
stain. A drop or two of the solution is placed on _wetted_
film or paper and left for a couple of minutes, they rinsed
off. It should leave NO stain if the emulsion has been
completely fixed.
With any fixer the capacity can be much extended by
using two successive baths. This technique extends the
ability of the fixer to completely fix from four to ten
times. Instructions for the technique and for the test
solutions can be found in the _Kodak Black and White
Darkroom Data Book_ I don't know if this is still published
but old editions have the same information in them.
The problem is that an exhausted fixing bath will
continue to clear emulsions long after it has become too
exhausted to completely fix out all the silver halide. The
complexes left in the emulsion will change over time to a
form which can no longer be removed by re-fixing and will
eventually destroy the image.


--
Richard Knoppow
Los Angeles, CA, USA
dickburk(a)ix.netcom.com