Negatives too stiff (newbie question?)

[Edimilson]

Hello!

Lately I've been processing my first Tri-X rolls. I've been trying to follow Kodak's guidelines. By following Kodak's guidelines I mean D76 (1:1) at 68º F for 8 1/2 minutes, 30s in citric acid and 8 minutes in Kodak fixer. Besides problems inserting the film correctly in the spiral, I've found my negatives to be too stiff after processing. I guess this problem is fixer-related. Am I right? Kodak only says the film must remain for 5-10 minutes in the fixer and 8 minutes seemed all right to me. Any ideas? Sorry if it's a dumb question!
(By the way, as to the quality of the images, some look good enough to me. I never thought I'd get anything usable in the first tries.)

 

[Mike Wilde]

do you mean residual curl?

If a roll film like 35mm film has been wound on the reel a long time it may want to curl up after processing, particularly if it has not been left hanging to dry with a weight ( a few clothes pegs etc.) clipped to the bottom. That explains end to end curl.

The across the film curl - what that comes from, I am not sure, but yes, it exists. Some films, after being left in plastic negative filing pages squashed into a binder for a while seem to flatten out. Otherwise the enlarger negative carrier generally flattens the negs as they get seated prior to exposure.

You don't mention it, but you are washing? Otherwise the hypo (sodium thiosulfate crystals) from the fixer would show once the film was dry. I have not tried to dry an unwashed film, but that could result in stiffness.

With time, you are likely going to see discussion of rapid fixers. They fix faster than what you are using, however what you are using is a great way to start. The 5-10 minutes guideline works like this. Take a bit if film - say the leader that you clipped off of the film that you just wrestled onto the reel (It does get easier with practice). Dangle it in the fixer in a cup. You can do this test with the lights on. The film clip will first go opaque. It will become clear. Note how long it takes to do this. Then fix your films for twice as long. With time, as the fixer is re-used, the amount of silver tied up in the fixer increases, and the ability of the fixer to clear the films a s quickly diminishes. Do the above 'clearing test' after say 5 rolls, then 10 rolls. That will teach you when you should be fixing longer. When the clip takes twice as long to clear as it did when fresh, then I call the fixer exhausted. I mix a fresh batch, and give the exhaused stuff to a local photo processing shop, who then on-sell it for a small amount to a silver recycling company. Otherwsie, label it, and turn it in at a hazardous waste facility. My local dump takes stuff like this, paints, used motor oil, etc. for free, while I pay to dispose of 'simple' garbage. Used fixer should not be idly poured down the drain.

 

[Edimilson]

Mike,

It is not exactaly curl. When I compare the negatives I processed to negatives that I had processed by professionals, I notice that mine seem less flexible.
I do leave my processed films to dry with a weight. I also wash them in running water for at least 20 m. What I noticed just some minutes ago is that the stiffness may be related to insufficient drying. I processed two rolls yesterday. One I left drying for only about two hours and the other for the whole night. The second one looked much better. Perhaps the first one will look better after some time (?).
As to the disposal of used fixer, I've been storing mine for the moment. I've been experiencing a hard time finding a way to properly get rid of it.
Thanks for the tips. I'll be sure to follow your advice, particularly regarding the test with a piece of film leader.
All the best!

 

[Captain_joe6]

I'm not entirely sure, but I believe that Kodak Fixer is a hardening fixer, which could explain some, if not all, of your film stiffness. Basically, it chemically hardens the gelatin layer on your film, which is nice because it acts as a guard against scratches and such. There's also a good chance that your photo lab doesn't use hardening fixer because it makes film easier to wash and also because fewer ingredients in the fixer = reduced cost (generally speaking). Unless for some strange reason you need your negatives to be flexible, then I wouldn't worry about it.

 

[Edimilson]

The fact just attracted my attention. I didn't know labs may use non-hardening fixers to lower costs. If stiff negatives don't seem to be a sign of trouble, then I won't worry about it.
Thanks very much!

 

[Captain_joe6]

Its not just to lower costs, but to lower the toxicity of the fixer itself. Hardening fixer can have some pretty nasty stuff in it, and usually, if not always, requires an acid fixer, which costs money, while a non-hardening fixer can be used with plain water, which is darn near free. There are several layers to this stiff-film cake.

 

[Ryuji]

I'm not entirely sure, but I believe that Kodak Fixer is a hardening fixer, which could explain some, if not all, of your film stiffness. Basically, it chemically hardens the gelatin layer on your film, which is nice because it acts as a guard against scratches and such.

This seems to be a very persistent misconception.

Hardener in fixer does not make your film more resistant to scratch or other mechanical damage. The mechanical strength of hardened gelatin is same as that of unhardened gelatin, once dried. The difference is in the wet strength, but even this is irrelevant with most modern films.

Gelatin can become very brittle in very dry condition, especially when combined with higher temperature.

It often happens that many minilab processed color films and hand processed b&w films don't feel the same but I don't think this is of particular concern, unless the lab processed film is tacky or grow mold rather easily.

Also, the stiffness of the film base can vary depending on the thickness, material, plasticizer used, etc.