Tri-X

[Tom1956]

I have noticed a pink color associated with T-max at some point in the process, but am perplexed that it would be the subject of a thread with so many remedies. I just don't have that problem. My standard chemistry has always been Microdol !:3, D-76 1:1, Kodak ISB, Kodak Fixer, standard powder from the pack. But the one constant I started early on when T-Max first came out was a pre-soak of a couple minutes before development, with water brought to developer temperature. I did this, not for any other purpose but to get the tank and reel to temperature so than when the proper temperature developer was poured in, the cold (or hot) steel tank would not throw off my dev temp. I say all this to note that when I pour out the water, it is as dark and murky as it can be. And from that, I never have any residual A-H backing, or pink discoloration. I'll stand by my pre-soak methods like a guard dog.It works.

 

[Lamar]

The batch of fixer I'm using is old so perhaps it's time to mix a new batch if 6.5 minutes seems long. I have started doing clip test now for every batch I process. I reuse chems so I should have been doing that all along but before I was just going on getting good results when I pulled the film out of the fixer after an 8 minute flat time and re-doing it if needed. Now I double the clip test clearing time for Tri-X and HP5 and triple the clearing time for T-grain type films, Tmax and Delta. Saw that in a post here on apug and it seems to work well.

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@ Lamar;
If you don't do a clip test in fresh fixer to determine the clearing time in fresh fix, you may be using exhausted fixer! Simply doubling the time of a clip test won't do the job. The fixer should be discarded (or moved to bath one in a two-bath regime) when the clearing time reaches double that in fresh fix. I rather doubt that it takes six and one-half minutes to clear Tri-X in fresh fix!

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[miha]

Michael, I know it's a complex and not fully understood process, still bleaching is when metallic silver is removed from the emulsion as well. I fail to see the roll of pH in this process.

re fixer beeing mostly acidic I can understand the reasons of the past, still times changed, and I see no reason why the major manufacturers haven't accommodate to contemporary materials if the only reason is hardening.

 

[Thomas Bertilsson]

Michael, I know it's a complex and not fully understood process, still bleaching is when metallic silver is removed from the emulsion as well. I fail to see the roll of pH in this process.

re fixer beeing mostly acidic I can understand the reasons of the past, still times changed, and I see no reason why the major manufacturers haven't accommodate to contemporary materials if the only reason is hardening.

There is a big difference between fixer and bleach.

Fixer is designed to only remove undeveloped silver halide.

Bleach is designed to reduce the amount of developed silver.

Acid fixer may still have a deteriorating effect on the developed silver after the silver halide removal has been completed.

About hardened emulsions - film chemistry sales today are not substantial enough to warrant a lot of research and development to come out with new fixers geared specifically to newer film materials. Since the old formulations for fixer still work, why fix what is not broken?
The availability of separate hardeners for non-hardening fixers should be interpreted as something you can use, IF NEEDED. For example, the Efke films had very sensitive and scratch prone emulsions when wet, and the same is true (to a lesser extent) for Foma emulsions. They could definitely benefit from a hardening bath, where Kodak and Ilford films simply don't need it.

Also, keep in mind that we are discussing something that has no real world effect on the outcome. Whether the slight pink tint of the film is removed or not, has no real effect on the outcome of either scans or prints. All of what we are discussing in this thread is largely unnecessary, except from an academic standpoint.

 

[Pat Erson]

My 2 cents :

DON'T FRET so much, buy Hypam, fix according to what Ilford recommeds (stop at 24 films per liter of stuff, diluted 1+4)
http://www.ilfordphoto.com/Webfiles/201142795282272.pdf

And stop worrying about the pink tint... it disappears with time.
Today I checked some TRI-X films from 2004 and the pink was gone : they looked blue-ish.

 

[miha]

About hardened emulsions - film chemistry sales today are not substantial enough to warrant a lot of research and development to come out with new fixers geared specifically to newer film materials. Since the old formulations for fixer still work, why fix what is not broken?

They were in the late 80s, early 90s, still smaller manufacturers put several alkaline and neutral fixers on the market, major didn't.

All of what we are discussing in this thread is largely unnecessary, except from an academic standpoint.

For what we APUGers are famous for

 

[pstake]

miha: just following up on the effect of pH on bleaching action. My primary source on this is Haist - "Another danger of long fixing bath immersions is the direct attack on the silver image by the combination of oxygen and the acid fixing bath. It is believed that oxygen from the air dissolves in the fixing bath and attacks the very finely divided silver particles of the image. Oxygen converts these metallic silver particles to silver ions by removing electrons. the silver ions are then complexed by the thiosulfate and removed, resulting in a loss of image silver. Fine-grained film and paper images are especially susceptible to image reduction by acid thiosulfate solutions.". The primary research cited is by Russell and Crabtree. He goes on to say "This attack does not occur in alkaline thiosulfate solutions..." "The rate of image reduction increases with the acidity, the degree of agitation, the temperature of the bath and the freshness of the bath. Active acid fixing baths of high acidity may be used to reduce the contrast of photographic silver images. Avoiding any unintentional image reduction requires that the minimum fixing time be used and unnecessarily long immersion times, especially during the processing of photographic prints, be avoided.".

In the discussion of rapid ammonium thiosulfate fixers he repeats the research findings: "The loss of silver image during fixation is directly proportional to the acidity of the bath. Ammonium thiosulfate fixing baths have greater reducing action than sodium thiosulfate baths at the same pH." "Photographic paper prints are especially susceptible to the destruction of their finely divided silver image.". The repeated references to finely divided silver would seem to indicate warmer toned papers/papers given less development would tend to be more susceptible than colder toned papers and/or papers given fuller development.

As Thomas rightly points out none of this should be of practical consequence unless we totally neglect our processing procedures.

I use alkaline fix. TF-5, which I believe is very near neutral but with our city water supply it goes a little alkaline. Is it possible that after repeated transfers from the acid stop, my fix will eventually get acidic before it's exhausted?

Also, is this thiosulfate the same thing responsible for the slight increase of highlights in selenium? Maybe that's a question for another thread.

 

[pstake]

TF-5 is very slightly acidic but essentially neutral. I'm a little surprised it would go alkaline since it is highly buffered (which is also why it is perfectly ok to use an acidic stop bath with it). PE would be the best person to ask when it comes to specific questions about TF-5. But presumably it is a formula balanced for the working solution to buffer against significant changes in pH during its useful life/capacity.

You'll have to clarify your question regarding the slight increase in highlights in Selenium. Not sure what you mean by that. Are you referring to prints? Are you saying the highlights get brighter? This shouldn't happen.

I say it goes alkaline only because it smells a little like Ammonia when I mix it. I haven't tested it for pH.

The question about selenium was because I seem to lose just a little bit of highlight detail, particularly in high-key prints.

 

[StoneNYC]

The pink is "normal" sometimes, HOWEVER, since using Hypo-clear AND extending wash times, I've not had the pink issue.

I noticed sometimes when the fix gets older, the pink appears at the end of the fix cycle, however I always pre-wash so it's not the anti halation later or anything that's causing it.

Anyway I have seen it pink after the fix cycle AND sometimes pink after the hypo-clear cycle if I'm re-using the clearing agent, but then I extend the wash times and it disappears ... So hope that helps.

 

[pstake]

Are you sure that is actually happening or could it be a subjective reaction to the slight increase in contrast (due to intensification of dark areas)?

Impossible! I'm always right! I thought I was wrong once but it turned out I was mistaken.

Seriously though, that may be what happened but I thought I had also read somewhere that selenium will reduce highlight detail. Oh well. Topic for another thread.

 

[Snapshot]

As other have said, extend your fixing time, use and alkaline/neutral pH fixer and extend your wash. You can expose the negatives to some daylight for about 20 minutes, which will clear up the pink hue as well.

 

[miha]

miha: just following up on the effect of pH on bleaching action. My primary source on this is Haist - "Another danger of long fixing bath immersions is the direct attack on the silver image by the combination of oxygen and the acid fixing bath. It is believed that oxygen from the air dissolves in the fixing bath and attacks the very finely divided silver particles of the image. Oxygen converts these metallic silver particles to silver ions by removing electrons. the silver ions are then complexed by the thiosulfate and removed, resulting in a loss of image silver. Fine-grained film and paper images are especially susceptible to image reduction by acid thiosulfate solutions.". The primary research cited is by Russell and Crabtree. He goes on to say "This attack does not occur in alkaline thiosulfate solutions..." "The rate of image reduction increases with the acidity, the degree of agitation, the temperature of the bath and the freshness of the bath. Active acid fixing baths of high acidity may be used to reduce the contrast of photographic silver images. Avoiding any unintentional image reduction requires that the minimum fixing time be used and unnecessarily long immersion times, especially during the processing of photographic prints, be avoided.".

In the discussion of rapid ammonium thiosulfate fixers he repeats the research findings: "The loss of silver image during fixation is directly proportional to the acidity of the bath. Ammonium thiosulfate fixing baths have greater reducing action than sodium thiosulfate baths at the same pH." "Photographic paper prints are especially susceptible to the destruction of their finely divided silver image.". The repeated references to finely divided silver would seem to indicate warmer toned papers/papers given less development would tend to be more susceptible than colder toned papers and/or papers given fuller development.

As Thomas rightly points out none of this should be of practical consequence unless we totally neglect our processing procedures.

Thanks for clarifying further Michael.

 

[Jerevan]

Possibly related in a way - you can see the bleaching effect in lith printing - compare ammonium vs sodium thiosulfate fixers; there is an obvious bleaching effect in the delicate highlights with the rapid fixers containing ammonium thiosulfate.