Kodak Professional Fixer: Estimated Lifetime Before Exhaustion?

[cooltouch]

Well, I used the search function here to see if I could find an answer, and I did, sort of. I read where some folks said that fixer has a relatively short shelf life and where others say it has a much longer one. I'm hoping for a bit more of an exact response. Here's my situation:

I've been away from the darkroom scene for many years, and got back into developing my own B&W about a year ago. Bought some D-76 and Kodak Professional Fixer (both in the envelopes), mixed them and stored them in brown 1-gallon containers, thus full almost to the top.

I ended up developing about eight rolls of film from this setup. I don't use a stop bath, I just let the film rinse for three or four minutes before pouring in the fixer. I figure the developer has sat too long and is exhausted, so I'll replace it. But I've read where fixer can last a long time, so I'm just wondering if I can expect it to have any life left.

I have a few rolls of B&W that I'd like to develop today, and unfortunately the only camera shops in this town that would carry fixer are closed on Sunday. I know I should be patient and wait, but why should I if the fixer is still usable? I mentioned the 'no stop bath' bit above in case this might have an effect on the fixer's life expectancy.

So, care to comment on what I might expect?

Honestly one of the rolls I shot is no great shakes to me if it comes out or doesn't, so I'm thinking at this point I should just use the old fixer with this roll and see how it turns out.

 

[brucemuir]

How many is "many years".

If it looks cloudy and had precipitate it's shot.

If not it may be okay and it's an easy test.

Drop a film leader in a small beaker with some of the questionable fixer and see if it clears the film and how long it takes.
Rapid fixer will clear some films in 30-60 seconds but I think the dry type you have takes longer.
Maybe 3 minutes to clear if it's good. (I haven't used any dry mix fixer for awhile so I could be off on this timing)

 

[cooltouch]

Thanks for the tip, Bruce. I'll give it a try directly.

 

[tkamiya]

I wondered about the same thing.

My limited experience shows that Kodak Professional Fixer lasts for at least 6 months and until the specified number of films or papers have been processed. The package says 2 month in stoppered bottle though. I keep a running tab of number of paper/film (separate bottles!) processed. As it approach 6 months and near the end of its process life, I start testing with clip of film just to be sure.

The longest I've kept was 8 months and at that point, it took 8 minutes or so to clear film (Tmax 400) so I discarded it.

 

[brucemuir]

Yea, 8 minutes seems way too long for the sodium thiosulphate type but it takes longer than the rapid Ammonium thiosulphate based fixers.

TK,
yours was mixed, was there any sulphur precipitate that was obvious?

I always assumed that most dry chemical mixes that Kodak puts out in those envelopes keep quite well and experience has backed this assumption. As long as the envelope hasn't been compromised and the mix isn't caked up or an odd dark color.

Of course developers are more sensitive due to any oxygen but I have D76 unmixed pouches that are at least 5 years old that work fine so far.

edit: I should mention that any times I'm listing DO NOT apply to TMAX films because they take longer to clear and will reduce fixer capacities as well.

 

[burchyk]

FYI I still use Kodak fixer that is 1 year old and that have seen some film and fiber paper. Don't remember the type exactly but its the one in yellow envelope. Given 20-30 minutes it does the job just fine. Use a small piece of exposed undeveloped film to do a test as suggested by brucemuir

 

[tkamiya]

Bruce,

Tmax film takes about 5 to 6 minutes to completely clear even when fixer is fresh. As to appearance, I wasn't able to see into the bottle as it is an opaque brown bottle. What came out of the bottle didn't have obvious change.

Are we talking about fresh one in bags or mixed in bottles?? The way I read OP's post was that he was talking about mixed working solution that sat for a while....

 

[brucemuir]

TK,
yes you are correct he does mention it is mixed already.

That changes things slightly

I mentioned in another thread where I used to get alot of cast off chemicals from the local Community College.
The kids would take one semester, move on and then leave a veritable treasure of next to new fixers, stop and opened bottles of Sprint developer. I would help clean the darkrooms for the monitor up there and she would let me have stuff rather than having to pitch chemicals and the issues that presents.

I would steer clear of the developer mostly but I always would grab the fixer and this was the liquid Kodafix ammonium thiosulphate based (somewhat rapid) variety. She marked them pertaining to what semester they were from.

Sometimes the Kodafix would be good after 3 years, sometimes it would have precipitate.
I realize this is highly unscientific and subjective I just thought I'd throw it out there.
What I take from it is Kodaks recommendations are generally conservative regarding expiration.

 

[Sirius Glass]

Testing the effectivity of fixer [not a conclusive list, just what I do]:

If it takes film ten minutes to clear, replace the fixer.
Put in a few drops of Hypo Check [any brand] and replace if the fixer causes a precipitant to form.​

Steve

 

[tkamiya]

What I take from it is Kodaks recommendations are generally conservative regarding expiration.

This is very true. I'm guessing they have to do that and error on side of caution because of potential liability. I wish it was somewhat closer to reality though. Last time we had this kind of discussion, most folks agreed that they use their fixer until exhaustion by number of rolls/prints processed. At least 6months and more than a year was quoted as I recall. Nobody mentioned the 2 months expiration period of working solution.

 

[removed account4]

hi cooltouch

call kodak up and ask how long they say it usually takes to clear whatever film you use in the fixer if
it was new and fresh mixed. generally speaking when it takes 2x the original clear time fixer is no good.
so if kodak says " with fresh fixer it takes 2 minutes to clear tri x " if it takes 4 minutes with your clip test,
get new fixer. fix is cheap ...

hypo check that steve mentioned works well if you follow the instructions.
i have a feeling hypo check will be of no use for you in this instance,
it checks for silver, i don't believe it will be of any use if you have unused ( but old ) fixer