Has anyone used TF-4 fixer for films? Can it be used with all types and brands of B&W films? What are the fixing times? Do you use a hardener with it? Thank you.

Francis

-- Francis T. Knapik (inirolem@aol.com), November 01, 2000

Answers

I've switched to TF-4 exclusively. I don't know of any silver-based film that won't work with it. Chromogenic films, however, require standard color chemistry.

Fixing times are incredibly fast. I usually clear the film in 30 seconds. I don't use a hardener, and don't seem to need one. Since my whole process (develop-rinse-fix) is now alkalai, the film never seems to soften at all.

I recommend this fixer highly.

-- Charlie Strack (charlie_strack@sti.com), November 01, 2000.

How do you work out that your film never softens in an all alkali process Charlie? Alkaline baths are precisely what does soften gelatine. Gelatine is a protein, and proteins are broken down by alkaline solutions. That's why alkaline chemicals feel slippery to the fingers; they're dissolving the outer layer of skin.
If you don't believe this, put some film into a 10% caustic soda bath for a few minutes and see how hard the emulsion is then.

-- Pete Andrews (p.l.andrews@bham.ac.uk), November 02, 2000.

Fixing times: 3 to 5 minutes for film; 30 seconds for RC paper, 60 seconds for fiber. No stop bath necessary. Mix with distilled water for a reduction in fumes. Hardner not required. Good stuff.

-- Christopher Hargens (ldmr@cruzio.com), November 02, 2000.

Regarding Pete's question:

How do I determine that alkakai fixer doesn't soften the emulsion? Empirically. The way I do with most things.

The 1st time I tray-developed 8x10 film (single sheet) the emulsion had a "solid" feel to it during developing and rinsing. Immediately upon submersing in the fixer (Kodak Fixer, at the time) which is acid base, it got soft, and I gouged it with my finger tips, not my finger nails.

With TF-4 this doesn't happen.

Now whether it's the absolute pH determining the softness of the emulsion, or the change in pH (delta-pH) causing expansion of the emulsion as the absorbed developer out-gases or expands the emulsion, I cannot say. I don't really care. I am only report what I experienced.

Others may have different experience, as water pH varies quite a bit throughout the country.

-- Charlie Strack (charlie_strack@sti.com), November 02, 2000.

Further to Pete's question:

Refer to my 1st post: I said never "seems", not that it never does. There is quite a difference in meaning, so please don't add meaning that isn't there. I'm usually quite specific in my choice of words.

-- Charlie Strack (charlie_strack@sti.com), November 02, 2000.

Well, all I can say Charlie is that your experience is completely at odds with my own, and with all known facts about the behaviour of gelatine in acid and alkali solutions.
I used to carry out precision copy work on both Lith and continuous tone film, from 10x8 up to 20x16 sheets, which had to be dish developed.
Those times when I didn't wear surgical gloves, I could feel the emulsion softening in the developer, and immediately hardening up in the acid stop bath. After it had been in the fixer for a couple of minutes, it was very abrasion resistant.

Another thing that wories me about TF4 is that it's claimed to be 'archival quality'. How do they know?
Here's my own empirical evidence: I have a personl collection of negatives, in formats from 35mm to 5x4, going back more than 30 years. I've always used an acid hardening-fixing bath. None of those negatives show the slightest sign of chemical deterioration or damage. Not even a detectable change of image colour. Not even on films that were just done as a quick test, where the fixing and washing time were shortened.
However, two complete 35mm films have been lost to fungal attack, and suspiciously, they were processed in chemicals that weren't directly under my supervision. I suspect that the difference may be that the fixer didn't contain any hardener, since they were given my usual wash time.
The storage conditions for the mouldy negs has been exactly the same as the others; in fact they were in the middle of a ring binder of glassine envelopes, sandwiched between perfectly good film.

Acid hardening fixer has been around a long time, and its results have stood the test of time. TF4 hasn't.

-- Pete Andrews (p.l.andrews@bham.ac.uk), November 03, 2000.

Further to Pete's latest post:

Pete, I want to re-iterate that my experience may not have been an issue of alkai softening (or not)the emulsion, but more of a mechanical phenomenon as the alakai developer and acid fixer mix. Most chemical reactions are exothermic or endothermic, and the resulting temperature change which could soften (or seem to soften?) the emulsion (perhaps moreso than the alkalai?), and the by products of the reaction could outgas, or otherwise cause a dimensional change resulting in a softening. Most parts of the photographic process involve multiple actions.

On the other hand, perhaps it isn't the emulsion at all that softens, but the top anti-scratch coat?

I must admit that acid-hardening fixers have generally worked well for me, but it seems that keeping the whole process on one side or the other of pH 7 seems a better situation than crossing the line.

In over 30 years and I have had only one instance where the negatives have not remained stable, though the process was the same. And the only 2 times I damaged negatives with acid fixer were: 1) when I used Kodak rapid fixer without the hardener (early in my photgraphic life), and 2) the 8 x 10 sheet film I first mentioned.

I've avoided acid stop baths with films lately as I've had several instances of pin holes. I live in the San Francisco bay area, and our water has lots of impurities, so I use distilled water for developer and fix. Perhaps that the source of my experiences?

Perhaps I'll experiment to see if I now get the same results as you.

As far as TF-4 being archival, your comments cannot be refuted. It hasn't been around long, and may not be archival. Personally, I don't care if my negatives don't outlive me.

-- Charlie Strack (charlie_strack@sti.com), November 03, 2000.

TF-4 is an excellent film fixer, especially when using (and Pete is going to hate this!) pyro developers. Because it is alkaline, it will not remove the pyro stain. Ilford no longer recommend hardening fixers, claiming that the emulsion is 'pre-hardened' during manufacturing. The tanning action of pyro is a much better 'hardener' especially because it takes place at the beginning of the processing proceedure in the developer. As to the overused 'archival' qualities of TF-4 or any other fixer: this is a moot point. After washing the film should contain NO fixer, hardener, or anything else. Providing the film has been completely fixed, the only thing that will affect the silver in the emulsion would be contanimation, sulfer fumes for example. Once washed and dried, hardeners have no effect on the hardness or scratch resistance of the emulsion, contrary to popular misconception. How do we know TF-4 is archival? The same way we know anything else is 'archival.' There are special laboratory aging tests that can determine this sort of thing, but it is really not important as long as the film has been given a proper wash. Of course if you put film (or any organic substance) into a 10% solution of caustic soda, it will be destroyed. Try putting film into a 10% solution of sulfuric acid and see if disolves! Silly argument, really.

-- Michael D Fraser (mdfraser@earthlink.net), November 05, 2000.

Epson recently used these 'special laboratory ageing tests' on their so-called archival inks and papers, and pronounced a figure of 100 years fade resistance.
The result? A real life expectancy of about 2 weeks before their prints turned orange.

-- Pete Andrews (p.l.andrews@bham.ac.uk), November 06, 2000.