Two bath fix question

From the Ilford Publication "Ilford Multigrade Papers - A Manual For The Darkroom" (Cat. No. 192 7328), p.25

Ilford said:

When optimum permanence is needed (up to 100 years) ... the ILFORD Optimum Processing Sequence at 68F(20C) is recommended ... The recommended processing sequence is as follows:

FIXING Multigrade Fixer (1+4) 60 seconds

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Obviously I have snipped out some bits and bobs, but nothing that affects either the factual detail or the sense of what is stated, and the sequence refers to using only a single, strong fixing bath.

On the same page, reference is made to possible use of a two-bath fix, but also notes that the single bath fix within the "Optimum Sequence" offers a capacity of 40 10x8s .

Now I have no skin in this game, I am not an advocate for one protocol over another and take PE's (and Doremus') strictures to test for proper fixation and washing as good advice for whatever one's approach to fixing is.

I'm simply pointing out that Ilford recommend clearly that single bath fixation is good enough for archival purposes. The fact that they refer to the "efficiency" of two-bath elsewhere might require clarification.

But tbh this subject has been thrashed to death over the years, and I'm not adding anything to the discussion over and above what PE and Doremus have said, plus I'm just an interested observer, so I'll leave it there.

M Carter said:

The "clip test" mentioned above is for film - as i understand it, film and paper do different things to fixer and you shouldn't test one for the other.

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with sprint products, if you use their whole "system" ( developer stop fix ) when the stop indicates .. the fix is gone too.
since i don't use their stop, i called sprint and asked if there was another way...
they told me the clip test monitors silver saturation, and can be used to test any fixer ..
speed fixer, hypo .. film or prints.
the bonus is with film it determine your total fix time, with paper you have to go by recommended fix times.

maybe i've been screwing up myprints and film? not sure ...
but i've been doing this for years ..
i can understand why someone would be nervous

YMMV

Think I'll keep to two bath fixing for 30 seconds + 30 seconds. Going to get some Ag fix test strips to see if the level doesnt raise above the professional 2 Ag g/liter.

pdeeh said:

From the Ilford Publication "Ilford Multigrade Papers - A Manual For The Darkroom" (Cat. No. 192 7328), p.25
"
When optimum permanence is needed (up to 100 years) ... the ILFORD Optimum Processing Sequence at 68F(20C) is recommended ... The recommended processing sequence is as follows: FIXING Multigrade Fixer (1+4) 60 seconds.
...
On the same page, reference is made to possible use of a two-bath fix, but also notes that the single bath fix within the "Optimum Sequence" offers a capacity of 40 10x8s .

Now I have no skin in this game, I am not an advocate for one protocol over another and take PE's (and Doremus') strictures to test for proper fixation and washing as good advice for whatever one's approach to fixing is.

I'm simply pointing out that Ilford recommend clearly that single bath fixation is good enough for archival purposes. The fact that they refer to the "efficiency" of two-bath elsewhere might require clarification.

But tbh this subject has been thrashed to death over the years, and I'm not adding anything to the discussion over and above what PE and Doremus have said, plus I'm just an interested observer, so I'll leave it there.

Click to expand...

pdeeh,

I'm just answering to clarify what I've emphasized in your post above, which is misleading (mostly because the Ilford information is somewhat vague and poorly distributed throughout their publications). However, Ilford very clearly states in the tech sheet on Rapid Fixer (the one on Hypam is identical) that the capacities for "commercial" and for "optimum permanence" for a single bath are 40 8x10-inch prints and 10 8x10-inch prints respectively.

Ilford then qualifies this with a couple of things. I'll let them speak and then comment later:

(from the Ilford publication "Processing B&W Papers")
"PRINCIPLES OF GOOD FIXATION
The biggest cause of premature deterioration of black and white photographs is undoubtedly poor processing technique, notably inadequate fixing and/or washing. In the case of fixing, this can mean times that are too long as well as too short.
Do not exceed the capacity of the fixer
Residual silver depends on fixer usage. There are three ways of keeping the residual silver to acceptable levels.
1 Fix only a few prints before replacing the fixing bath (approximately 10 20.3x25.4cm (8x10 inches) prints in one litre/US quart of working strength fixer).
2 Use two-bath fixation.
3 Use a single fixing bath plus a washing aid. The number of prints through the single fixing bath can be increased to approximately 40 20.3x25.4cm (8x10 inch) prints per litre/US quart of working strength fixer.
Use short times in a ‘rapid’ fixer, such as ILFORD RAPID FIXER
This reduces the absorption of thiosulphate by the prints and thus makes them easier to wash.
Use a non-hardening fixer, such as ILFORD RAPID FIXER
Hardened prints take longer to wash. If a hardening fixer is preferred, use a second fixing bath with a non-hardening fixer."

Note that Ilford states 10 8x10s per liter as base capacity for "optimum permanence." This capacity can be extended in two ways: 1. two-bath fixing and 2. using a wash aid.

Ilford states that the use of a wash aid (as in its published sequence for optimum permanence) will quadruple the fixer capacity. there are many of us who are a bit skeptical of that (there was an in-depth thread on precisely this somewhere here on APUG). Furthermore, there are some that don't place 100% confidence in Ilford's archival sequence or who, like me, find it unwieldy. Ilford also clearly states that "throughput is only a guide," which makes their capacity suggestions averages at best. Therefore, many of us prefer to err on the side safety and to not attempt to get the maximum number of prints out of a certain amount of fixer.

Testing with strips or clips would be easier than doing residual silver tests. Unfortunately, neither of these methods (nor the HypoCheck drops) are near sensitive enough to let you know when the fixer has reached 0.5g/l of residual silver. Underusing fixer and testing your workflow for residual silver are really the best tools we have, albeit a bit of a PITA.

Best,

Doremus

Oh for the days when it was all just a question of putting a few spoonfuls of hypo in water, sloshing your print about in it for a bit then leaving it under a running tap until you needed to use the sink for something else. And nobody thought about archival permanence because they were long dead before the prints turned brown and started to silver out ...

jnanian said:

with sprint products, if you use their whole "system" ( developer stop fix ) when the stop indicates .. the fix is gone too.
since i don't use their stop, i called sprint and asked if there was another way...
they told me the clip test monitors silver saturation, and can be used to test any fixer ..
speed fixer, hypo .. film or prints.
the bonus is with film it determine your total fix time, with paper you have to go by recommended fix times.
YMMV

Click to expand...

When using the test I described - unless I'm really missing something - you should know exactly how long a given batch of fixer takes to clear a given brand of paper, regardless of the fixer's age or dilution. (Bonus: you'll also see the max black your developer is capable of in its current condition). Like the film-snip test, I tend to take the test results as a "minimum time". (I didn't make this test up either, it was suggested here and when I purchased "way beyond.." it was detailed there as well.

This is really a vital test for lith printers who want to preserve color - you really need to know the minimum fix time if you don't want to bleach out the colors.

M Carter said:

When using the test I described - unless I'm really missing something - you should know exactly how long a given batch of fixer takes to clear a given brand of paper, regardless of the fixer's age or dilution. (Bonus: you'll also see the max black your developer is capable of in its current condition). Like the film-snip test, I tend to take the test results as a "minimum time". (I didn't make this test up either, it was suggested here and when I purchased "way beyond.." it was detailed there as well.

This is really a vital test for lith printers who want to preserve color - you really need to know the minimum fix time if you don't want to bleach out the colors.

Click to expand...

hey, thanks !
i missed the test you mentioned and had never heard or read that before.
i love learning new stuff like this !
i always went by the paper manufacturer's recommendations i never knew tests like this existed .
apug is a great resource, thanks !
john

Wiser heads please comment - Could I increase the useful capacity of my fixer by using electrolytic silver recovery (I have a "Silver Magnet ) ?

Smudger said:

Wiser heads please comment - Could I increase the useful capacity of my fixer by using electrolytic silver recovery (I have a "Silver Magnet ) ?

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hi smudger
ive been asked that before, and when i asked the manufacturer they said
electrolytic extraction changes the fixer so it can not be reused.

jnanian said:

hi smudger
ive been asked that before, and when i asked the manufacturer they said
electrolytic extraction changes the fixer so it can not be reused.

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Hi John, actually it's doable providing that the current is kept low enough to prevent "sulfiding." (I'm guessing that the silver magnet's plating current IS low enough as long as the fixer has substantial silver in it - say over a couple grams per liter.) Aside from that possibility, the main detrimental effect is the loss of some sulfite ion and a slight pH shift. This is relatively insignificant for small amounts of silver removal, say a couple grams per liter.

Having said this, I don't recommend in-line silver recovery because of the possibility of things going wrong. Even if one knows how to handle the details, it's still an extra headache for not much benefit. One can get the same benefits, environmental and chemical savings, by adding an extra fixing stage then doing terminal desilvering at the end.

As a note, at the large outfit where I spent some time, we did experiment with regenerating C-41 fixer initially. But only a small proportion of fixer could be reused - the iodide build-up from film drastically slowed down the fixing.

thanks mr bill !
my uneducated and uninformed guess
is maybe the variables you mention can be kind of tricky
and the manufacturer didn't want to be held iiable if someone
did it wrong and had troubles. people often times contact me
because they didn't have enough silver and that caused trouble
seems it is less trouble to me to just make a new batch of fixer
rather than keep wearing down the same batch and have it potentially
mess with ones film and prints.

HI again, John. if I had to guess, I'd say that when using the silver magnet as intended - for terminal desilvering - some sulfiding will eventually occur (this is a consequence of continuing to run current beyond the point of "enough silver" left). So in this situation, I'd say they are correct, that the fixer is changed and not fit to use.

But stopping short of this point is a different story, and if silver concentration is reduced without sulfiding then the life of the fixer can be extended. But like I said, I think it is preferable to forget about inline desilvering, and to extend the life of the fixer by adding another stage, if desired, and preferably using replenishment. IF...it's economically worth the trouble, which is not likely for a home processor.

i had a feeling you were going to say that, mr bill.
its sort of like a goldielocks situation: you have to know when "just right" is
which might be easier in a giant processing situation with controls &c but the average home user
won't have the means to be as precise ... while i use speed fixer for most things, i have started to
use kodak hardend fixer out of the pouch which is pretty cheap, and from time to time i buy 5-10lbs of
hypo "rice" from adorama who tends to sell it at an absurdly low price on a regular basis.
i figure, life's too short to fiddle around with saving a few dollars here or there when fixer isn't too expensive to begin with
its like home brewing photoflo, it costs about 0.5¢ each use ( 3-4 drops ) and a small container lasts 20 years .. its not
worth the effort. besides even if dish detergent or jet dry didn't screw up film to begin with, it probably costs more than photoflo.

thanks again for your expert perspective !
(i'm admittedly clueless but learning )
- john