How does un-finished "fix" film look like?

[Morituri]

Weird headline, let me explain.

I'm going to try to save up on using fixer a bit, I aint made of money So how does a piece of film look like when it's not done "fixing" yet completely? So I'll know to fix it for a little bit more.

Pictures of film that is almost there but not quite done fixing yet would be appreciated.

Thank you!

 

[holmburgers]

Fixing for less time won't really save you any fixer, right? It just means you won't fix your film properly. What fixer are you using? Maybe there's a more affordable option..

This is what Ansel Adam's calls "False Economy"; if your pictures are destroyed in 10 years, was it worth saving a couple pennies on fixer??

 

[Monophoto]

I think this is false economy - you may save a few pennies on fixer, but you will waste dollars on improperly processed film.

But to answer your question, the purpose of fixing film is to remove the unexposed, undeveloped silver. So film that is severely underfixed has a gray haze from the silver that is left in the emulsion. However, there are gradations - film can be underfixed with no visible indication. The fact that it is underfixed means that there is a risk that as time goes by, the film will acquire stains (typically, yellow) that results in blotched prints.

 

[Morituri]

Oh I should clarify! How stupid am I.

I was thinking, I am going to (well, might do) re-use, and I need to know when I re-use a fixer a second time (and I think I'll only use it twice) how a film will look like when it's not done fixing the second time. I use Tetenal Superfix Plus by the way.

 

[MattKing]

To elaborate on what holmburgers posted - once the film is fully fixed, leaving it in the fixer longer does nothing to the fixer. So over-fixing doesn't decrease the life of your fixer.

Under-fixing may save a little bit on the fixer, but it will render your film vulnerable to damage, and film is a lot more expensive then fixer.

 

[holmburgers]

Oh I should clarify! How stupid am I.

I was thinking, I am going to (well, might do) re-use, and I need to know when I re-use a fixer a second time (and I think I'll only use it twice) how a film will look like when it's not done fixing the second time. I use Tetenal Superfix Plus by the way.

Everyone reuses fixer! Generally speaking, no fixer is used as a "one-shot" or even a "two-shot". Unless Tetenal Superfix is somehow different...

I think you'll be happy to know that fixer quantity is based off the number of square inches put through it. A liter can usually handle nearly 100 rolls of film (IIRC).

There are also simple testing solutions to test your fixer capacity.

 

[MattKing]

Oh I should clarify! How stupid am I.

I was thinking, I am going to (well, might do) re-use, and I need to know when I re-use a fixer a second time (and I think I'll only use it twice) how a film will look like when it's not done fixing the second time. I use Tetenal Superfix Plus by the way.

I re-use my fixer all the time!

The fixer will most likely have information on its capacity on the label. It will indicate something like 1 liter of working strength solution has the capacity to fix X rolls of film. Some times you need to do some arithmetic to figure out the capacity of the volume of working solution you use, and sometimes you need to filter the working solution to keep it clear.

With the fixer I use, I mix up a liter of working solution and count the rolls I put through it. I'm cautious, so I usually limit my use to about 2/3 of the manufacturer's rated capacity. I check it regularly though, measuring the clearing time on a piece of film leader.

EDIT: holmburgers beat me to it. I'd be cautious though about his guess on capacity. When it comes to the capacity of the already diluted working solution, 1 liter is more likely to have the capacity to fix something like 20 rolls. As an example, the data sheet for the Ilford Hypam fixer I am currently using indicates a capacity of 24 rolls per liter of working solution.

FURTHER EDIT: Calumet UK has your fixer on its website, and the listing provides capacity information.

They indicate that if you are using the 1 + 4 film dilution, the capacity is 18 rolls per liter of working solution.

 

[bblhed]

Fixer can no longer be used when it takes so long for it to fix your film that you can't stand to wait that long for your film to be fixed. Look around for how to test your fixer this is generally done by taking a piece of unprocessed film and putting it in fixer and seeing how long it takes to clear, that is your fix time. Normally most people give up and make up new fixer around ten minuets, seven is better, your tolerance might be higher or lower. I have some fixer that is at almost 11 minuets now, and the only reason it is still in the jug is because I haven't had the time to make more. The only reason I didn't make more last time is because I was only processing a test roll, and didn't make up more the last time when it took about 9+ minuets to fix my film.

 

[degruyl]

Also, straining the fixer (filtering) will remove any residue that could deposit on your film as you reuse it. Be careful. To my mind, the big issue with reusing fixer is the deposition of solids on the film (which leaves spots / flecks).

Don't get me wrong. I reuse fixer. I just use a filter before pouring the fixer back into the bottle. It seems to help.

If you are processing 35mm, the film leader is a perfect piece to check the activity: do a clearing test and double the time for how long you should fix in the tank. You can do this in a tray in normal light, since you are just fixing a piece of film. It should come out completely clear anyway.

 

[hpulley]

For paper you can dilute fixer further. It takes longer to fix but it is OK but they don't recommend it for films.

I reuse my fixer and test it before I work. I don't want to have to refix film so I chuck it when it is taking too long to fix.

 

[Maris]

For the information of terminally curious darkroom workers black and white film can be inspected safely before fixing if it has had a good soak in acid stop bath. Provided the pH is low no development will happen and the additional silver deposited by the inspection exposure is so small I've never measured it. The sight of a negative silver image embedded in a milky emulsion is decidedly underwhelming.

 

[removed account4]

do a clip test.
take a piece of the end of yout 35mm film and see how long it takes to clear when it is
brand new fresh made fixer. always fix for 2 times the time it takes to clear the film,
and get rid of fix that takes 2x the original time it took to clear ..

 

[holmburgers]

Could someone define what it means for the film to "clear". I tried a snip test with some really old TMAX 400 last night and indeed it became transparent, but the dye stain never left. Is "clear" just that, the time it takes to become transparent, regardless of any stain?

 

[hpulley]

Could someone define what it means for the film to "clear". I tried a snip test with some really old TMAX 400 last night and indeed it became transparent, but the dye stain never left. Is "clear" just that, the time it takes to become transparent, regardless of any stain?

The dye won't come out with fixer, try hypo clearing agent. Also, T-Max 400 takes longer to clear than most other films. Honestly, Delta 400 is simpler to work with, no dye and normal clearing time it seems to me.

 

[holmburgers]

Ok, good to know.

Yeah, this Kodak dye-stain thing caused me about 3 hours of grief and unncessary darkroom toil last night... and not the fun kind.

 

[fschifano]

The dye in Tmax films does indeed come out in the fixer if the fixer is fresh. If the dye doesn't come out and the fixer is still good, a soak in a few changes of water at processing temperature will leach it out.

 

[hrst]

"Clear" just means it's not milky anymore, so you can see through it. For example, try to read some text looking through the film - keep a small distance (an inch, perhaps) between the text and film, this way the milkiness will prevent you from seeing through. Use enough light when doing the evaluation.

Milkiness is caused by silver halides, the light-sensitive element of the film, they are somewhat translucent but not transparent. Fixer's task is to remove them completely from the film. When the film is visually clear, the bulk of them are removed. This time is at least doubled to ensure that A) all of them are removed, B) also the byproducts are removed.

Dyes in some films are a completely different matter, and manufacturers suggest that a small tint is perfectly normal and does not cause any problems. Most of the tint should come off in normal fixing and washing. If it does not, it is more important to check if the fixing and washing both are sufficient -- the excess dye is more like an indicator of a problem, than a problem itself.

I think that you should primarily follow the instructions on the particular fixer you use for capacity - just keep book on how many films you have developed. Do it so that you have doubled the fixing time for the last film, or something like that. Or, you can do this: when your film takes twice as long to "clear visually" compared to first film (of same kind of type!) processed in same fixer, it's time to toss the fixer. For example, the first film may clear in two minutes, so fix for at least four minutes. Then, after you have processed around 10 - 15 films per liter (depends on fixer and films), it may clear in four minutes, so you fix for eight and then toss the fixer.

 

[holmburgers]

Thanks guys.

I've since found that you're right; the dye cleared in the wash and HCA. I am keeping track of my fixer capacity, but I started to worry that maybe my water was bad, etc. etc. and just got worried.

All's well now!

 

[Photo Engineer]

There is no accurate visual test for fixing film or paper or for washing them. The only real tests are the retained silver test and the retained hypo test for fixing snd washing. The 2x time to clear is only a very general approximation that is not very accurate with some films!

PE

 

[Anon Ymous]

My rule of thumb is to fix for 3x the clearing time, with a minimum of 5' and regular agitation, in a non hardening, rapid fixer. So far, I've never had a silver retention test fail. This also assumes reasonably fresh, not overused fixer (Ilford Rapid BTW, 1+4).

 

[Pat Erson]

I use Tetenal fixer but the "up to 4m² of paper per 1 litre of working solution" mention leaves me puzzled...

 

[paul_c5x4]

The comment made by Simon Galley on this thread: (there was a url link here which no longer exists) might clear things up - Just to reiterate, it is the build up of silver and change in ph levels that limits the capacity of a litre of working solution.

 

[Photo Engineer]

I'm going to have to add that it is the amount of Iodide present, and also the amounts of Ammonium vs Sodium ions in the fixer. These too are potent in changing the activity of a fixer.

See earlier posts in the referenced thread.

PE

 

[ozphoto]

I too use the "unexposed film" method to determine whether to mix a new batch or not. For me, if it's longer than 7 minutes, I dispose of it into a 40L drum that gets collected by my mechanic for correct disposal.

 

[pentaxuser]

For the information of terminally curious darkroom workers black and white film can be inspected safely before fixing if it has had a good soak in acid stop bath. Provided the pH is low no development will happen and the additional silver deposited by the inspection exposure is so small I've never measured it. The sight of a negative silver image embedded in a milky emulsion is decidedly underwhelming.

If I have understood you correctly, you can inspect for development after a good soak in stop bath? If my conclusion is correct then presumably if you are trying a new developer/film combo and can't be sure about how long to develop, can you then replace the film in the tank, thoroughly wash away the stop and then refill with dev and continue to develop?

Ideal if you haven't yet determined the correct dev time. How long is a good soak and how long have you got to safely inspect?

Thanks

pentaxuser