Fixer failure.

[Mike Kennedy]

I ruined 3 rolls of tri-x film last week and traced the problem back to exhausted fixer. This is the first time in 5 years of processing, and many other mistakes, that this has occurred.
If I outline my methodology maybe someone can suggest a better approach. Mix Kodak Professional rapid fixer (liquid) to make 1 U.S Gal. of working solution and store it in a Delta 1 container. I then decant the liquid into a 1 litre plastic bottle and use that for 5 single developments before I get rid of it.

Any Suggestions?

 

[David A. Goldfarb]

Sounds reasonable enough. Sometimes the fixer can go off as a result of age or maybe exposure to high temperature, so if you haven't done any processing for a while, you might clip a film leader and do a leader test, just to be sure it's still good. You can also use a hypo-check solution, such as the one made by Edwal.

Have you tried refixing those three rolls? They might be salvageable.

 

[reellis67]

I ruined 3 rolls of tri-x film last week and traced the problem back to exhausted fixer.

I always check my fixer with the film leader for every developing session. I usualy only do one to three rolls in any given session, but if you are doing more, I would check the fixer every third roll. Just drop the leader in and time how long it takes to clear. Fixer should be tossed after the clear time doubles from when you first mixed the fixer. If your main container of fixer sits for a while, it could be the source of your problem. I keep mine in 1L air-evac containers so that there is no air exposure for the bottles that sit for months before use.

- Randy

 

[Photo Engineer]

Don't forget that you can sometimes retrieve underfixed film by refixing in fresh fix and then rewashing.

It isn't perfect, but you can get usable negatives sometimes.

PE

 

[david b]

Sorry to hear about the bad fix. I use Edwal's Hypo-Chek to see if the fix is bad.

I normally do 15-20 rolls per liter before it goes bad. If you are only doing 5 rolls per liter, you're wasting a lot of money.

 

[Bob F.]

I use a belt & braces approach to fixer (the only time I do get anal about such things) and test clearing time with a cut piece of leader and use the Tetenal test strips that test for silver and ph levels before each run. I've used exhausted fixer too many times in the past to want to do it again. Sometimes it just seems to die for no obvious reason ('tho I'm sure there is a good reason: most likely me, messing something up!).

Cheers, Bob.

 

[Tom Hoskinson]

I've gone to one shot fixing with film.

With paper, I use two bath fixing and mix new fixing baths for each printing session.

 

[Donald Qualls]

I'm heading in the direction of either two-bath or one-shot fixing for film, too. I had a batch of fixer go bad (probably just from overuse) a few months ago; fortunately, I had some more concentrate on hand -- but now, the bottle I store the working fixer in has turned completely black, presumably due to silver deposited on the inside; there's also a distinct "filter factor" to the fixer, especially if I shake up the jug before pouring, that I presume to be extremely fine metallic silver in suspension.

Seems to fix the film just fine and I don't detect it leaving spots on the film, so I'm not worrying about it, but when I get money I should get some tray cleaner...

 

[PeterB]

I use a belt & braces approach to fixer (the only time I do get anal about such things) and test clearing time with a cut piece of leader and use the Tetenal test strips that test for silver and ph levels before each run. ......Cheers, Bob.

How can I do the "clearing time" test for my paper fixer?

thanks
Peter

 

[reellis67]

I think for paper the only thing you can do is to use a hypo check solution. It clouds up when the fixer is exhausted.

- Randy

 

[Bob F.]

How can I do the "clearing time" test for my paper fixer?

thanks
Peter

Not so easy... There is a method outlined in the book "Way Beyond Monochrome". IIRC, someone detailed it in another thread a few weeks ago. Basically you can let small bits of paper get exposed to light and then dip each in the fixer for a series of times (one for 5secs, one for 10 secs, one for 20 secs etc) - mark the time on the back of each piece of paper (put them in the stop bath for a minute first to simulate normal working conditions). Give a good wash for a few minutes to get most of the fixer out (don't want it in the developer). Then put them in the developer for the normal time (you can do all this in normal room light). The strips that do not start to turn darker than paper white are properly fixed. Best to allow the usual double time for a safety margin.

However... I just use film header and the Tetenal strips as I do for film.... much quicker... I chuck the fixer when clearing time for the film is 50% longer than it was for fresh fixer or if the test strips show too much silver (but that's never happened yet).

Cheers, Bob.

 

[srs5694]

I would check the fixer every third roll. Just drop the leader in and time how long it takes to clear. Fixer should be tossed after the clear time doubles from when you first mixed the fixer.

Note that the initial clearing time can vary a lot from one type of film to another. In my experience, Foma films have very short clearing times, while T-grain films have very long clearing times. One of these days I'll get organized and store hard data on the clearing times of the films I use most often in my favorite fixer.

 

[david b]

Using fix one time is expensive and wasteful.

Use this product before and after using your fix and you will be fine.

 

[Saganich]

I switched to a two bath fixing method. I use the first bath to clear keeping an eye on the time; when clearing time reaches about double for a fresh batch I change it. The second bath lasts a really long time. I have yet to make a new liter since starting the new process (about 25 rolls). I've pulled rolls out of the fix after a minute to check for clearance time to find them milky. I mixed some fresh fix and they came out fine, no difference. I also discovered that the anti-halation purple stuff comes out with proper washing and as far as I'm concerned has little to do with fixing time. Washing film properly is a pain in the ass, throw your film washer out it may seem easy but it ain't doing a good job!

 

[David A. Goldfarb]

So does anyone use a pH meter to test their fixer? I have one, and I've been tracking the pH drift of my fixer (TF-4) as I use it, figuring that if I know the starting pH (about 8--TF-4 is an alkaline fixer) and the pH when it crashes, I'll be able to use those values to test in the future, but I don't know if pH alone is enough of an indicator to tell whether the fixer is still good. The pH is now about 7.6, and it's still good. TF-4 doesn't seem to have a gradual decline period. It works perfectly for a long time, then suddenly dies.

 

[PeterB]

Not so easy... There is a method outlined in the book "Way Beyond Monochrome". IIRC, ..... However... I just use film header and the Tetenal strips as I do for film.... much quicker... I chuck the fixer when clearing time for the film is 50% longer than it was for fresh fixer or if the test strips show too much silver (but that's never happened yet). Cheers, Bob.

Thanks Bob,

I also have the Tetenal Fixing Bath Test Kit, however I wasn't sure how the silver levels reported by the test strips related to the clearing times - in fact by using the test strips in my paper fixer, there is no real need for me to also do the equivalence of a "clearing time test" for my paper fixer.

regards
Peter

 

[Tom Hoskinson]

Using fix one time is expensive and wasteful.

Actually, when fixing film, it is neither expensive or wasteful to use the small amount of either Ammonium Thiosulfate or Sodium Thiosulfate required to fix roll or sheet film as a one shot.

Fixing fiber based paper is a different story. In that case, I use 2 fixing baths and fix the whole batch of prints from a printing session. I mix fresh fixer for each printing session.

 

[Tom Hoskinson]

So does anyone use a pH meter to test their fixer?

Yes David, I do - as reported in my APUG thread that discusses my testing of Fine Arts Fixer.

You do need to be careful that you don't damage the electrode in your pH meter. See Ryuji's post on this issue.

 

[gbroadbridge]

How can I do the "clearing time" test for my paper fixer?

thanks
Peter

You don't. You read the bottle which will normally state 80 8 x 10 prints per litre RC prints (halve that for FB)

Count the prints (not the test strips)


Graham.

 

[gbroadbridge]

So does anyone use a pH meter to test their fixer? I have one, and I've been tracking the pH drift of my fixer (TF-4) as I use it, figuring that if I know the starting pH (about 8--TF-4 is an alkaline fixer) and the pH when it crashes, I'll be able to use those values to test in the future, but I don't know if pH alone is enough of an indicator to tell whether the fixer is still good. The pH is now about 7.6, and it's still good. TF-4 doesn't seem to have a gradual decline period. It works perfectly for a long time, then suddenly dies.

That will track pH but what about dissolved silver and other contaminants?

Every fixer manufacturer states in their data sheets acceptable levels for silver, are you testing those levels. Archival prints need < 2mg/l silver before conversion (using toning).

Fixer is cheap, Use it for the 80 sheets per litre and then throw it away.

 

[reellis67]

Note that the initial clearing time can vary a lot from one type of film to another. In my experience, Foma films have very short clearing times, while T-grain films have very long clearing times. One of these days I'll get organized and store hard data on the clearing times of the films I use most often in my favorite fixer.

Very interesting. I only shoot three films, all of them Ilford, and as far as I can tell, the clearing times are so close as to be indistinguishable.

- Randy

 

[Nick Zentena]

I don't think this was mentioned. What are the odds the fixer failed on only the last few rolls? More likely it wasn't doing a good job with the film before it failed.

 

[David A. Goldfarb]

That will track pH but what about dissolved silver and other contaminants?

Every fixer manufacturer states in their data sheets acceptable levels for silver, are you testing those levels. Archival prints need < 2mg/l silver before conversion (using toning).

Fixer is cheap, Use it for the 80 sheets per litre and then throw it away.

That's really what my question is about. pH is just one indicator, but is it enough? It may be the case that silver levels in the fixer change in a way that corresponds to the change in pH, or it may not, hence my question. I'll dig up Tom Hoskinson's thread, and see what he's posted there.

I always use fresh fixer for prints, so this is just for my film fixing tank, which I top off with fresh TF-4 as the level drops and reuse.

 

[Ole]

The pH is irrelevant! Both acidic and alkaline fixers work. Some of both kinds are buffered, some are not. So the amount of stop bath or developer carryover it takes to change the pH varies wildly!

The total silver level affects the ability of the fixer to absorb even more silver, as well as the stability of the fixed material. But a strong fixer will still fix adequately with twice the silver content that would exhaust a weak fixer.

Total thiosulfate activity is a better indication, but that's more difficult to measure. The best way may well be the clearing test...

My conclusion is that if I'm in any doubt at all, I mix new fixer. It may sound expensive, but it's a lot cheaper than driving 200 miles to reshoot.

 

[Photo Engineer]

Having formulated several salable fix and bleach fix products for Kodak, I have developed a reliable set of quick laboratory tests for them. None are remarkable and none are unique to me, just adaptations of things already known.

I suggest the Formulary because they have everything all pre-packaged as a set of hypo test solutions that work and have good instructions.

1. Fix tests for papers. Fix small strips of paper for 15", 30", 60" and 2'. Wash these strips for the same time as they were fixed so you have 4 strips of paper. On each, place oned dot of Formulary residual silver test solution (silver sulfide in water) and one dot of Formulary residual hypo test solution (silver nitrate in acetic acid and water). The tests will tell you the minimum fix and wash times needed for that particular fixer at that stage of exhaustion. Fresh fix (TF-4) will result in a time of about 30" fix and about 1 - 2' wash with Ilford MGIV. I have reported this elsewhere.

2. To test for exhaustion, make up the Formulary fixer test solution (KI in water) and add to a small sample of fixer. If you get a heavy yellow precipitate, the fixer is exhausted. This test is not entirely reliable with high activity fixes such as super-fix, but gives a rough indication.

3. Acid fixes are bad when you see them begin to get cloudy and/or you smell the odor of rotten eggs when you open the container. Acid fixes spoil more easily than alkaline fixes due to the acidity which causes decomposition of hypo.

Over use of fix is false economy. But, underuse of fix is wasteful. Follow the mfgrs guidelines. I have tested them well and they are pretty accurate. Minimum fix and wash times vary by manufacturer due to type of emulsion, thickness of layers, and type of support. RC takes less time to fix and wash and FB takes longer. All film takes longer to fix and wash than paper due to the level of materials coated.

You can over fix and over wash. See the article by Ctein for details on that.

PE