TF-4 fix

[Tom Hoskinson]

I always thought the benefit of this fixer was the elimination of Hypo Clearing Agent bath for Fiber prints. One less step, one less tray. Am I wrong in belieiving this is true. So far none of my prints have turned yellow.

Different subject. I have been discussing the use of HCA for removal of residual antihalation dye in film - post fixing.

 

[Daniel Lawton]

Just a question for all you TF-4 users. For the water bath do you using running water or just a tray full of water. Oddly enough I find using a water bath to be more of a hassle than an acid stop. Due to my set up I can't place my trays next to a sink so if I were to use a water bath I would have to carry the print ove to a sink and then back to the fixer. Instead I have just been filling up a tray full of water and replacing it every 5 prints or so. Since an acid stop is not advised with TF-4 I find this to be more trouble than its worth and will probably go back to my standard fix as a result.

 

[galyons]

Just a question for all you TF-4 users. For the water bath do you using running water or just a tray full of water. Oddly enough I find using a water bath to be more of a hassle than an acid stop.

I just use tap water in a tray. I change it after a few (5 to ??) prints. No hassle whatsoever.

Cheers,
Geary

 

[Ole]

Jay,
it is quite possible to get dry ammonium thiosulfate, at least on this side of the Atlantic. I have a few kilos in my darkroom, but at present I use the sodium thiosulfate/ammonium chloride combination; at least until I run out of one of them. Which isn't going to be soon, as I bought 25kg Na2S2O3 and 2 kg ammoniumchloride last year.

The water "stop" isn't a stop; all it does is wash off some of the developer. I use a tray of water - unspecified amount, unspecified number of prints for an unspecified time. At the end of a session it is brown with spent developer. But it still washes off (or in some other way "kills") enough of the developer that the fix lasts as long as it needs to. My prints are fully developed, so it matters not at all if they continue to develop in the fixer. Any residual developer will be removed in the final wash.

 

[Donald Qualls]

I've been thinking about making up a neutral/alkaline fixer starting from sodium thiosulfate (rice crystals, sold for pool maintenance, seem an inexpensive source), and using a neutral mix of clear household ammonia and acetic acid to provide ammonium ion for rapid fixing effect, and near-neutral pH for odor avoidance -- likely without involving sodium sulfite, since this could/would be used one-shot economically, and mixed immediately before use. Anyone done this or something close?

 

[Ole]

Something similar, yes...

Sodium thiosulfate and ammonium chloride makes a great rapid fix when mixed. using ammonia and acetic acid seems to me to be unnecessarily complicated, you would have to be very exact to get a neutral result.

Another nice shortcut is to use 60% ammonium thiosulfate directly: Use a dilute developer like Neofin Blau, Rodinal or similar. At the end of developing, pour in 1/3 of the developer volume with 60% ammonium thiosulfate, shake well. Together with the alkalinity of the developer, the film should fix in a few minutes. The fixing will proceed fast enough that development should stop in seconds!

 

[rjr]

Thom,

I know, I´m late. ,-)

I´m using alkaline fix for just short of a year - but not TF4, which isn´t available in Europe, but ordinary rapid fix designed for color film processes like E6 and C41.

It functionally identical but readily available _everywhere_, from pretty much any dealer of photographic materials and it is much much cheaper.

I pay 6EUR for 2l concentrate of Calbe FX-R, which are good for some 10 litres of solution.

Another brands is Agfa Universal-FX, but that stuff is available from pretty much every major manufacturer, incl. Kodak, Fuji-Hunt and Tetenal.

To prevent my paper fix from exhaustion I use a stop bath of citric acid (a pleasant smell) and two-bath fixing. With film I give it a wash with water (and at least two changes) between fix and stop.

 

[Donald Qualls]

Ole, my thought was to use Indicator Stop Bath to titrate with the ammonia -- add ammonia until the mixture changes to the "exhausted" purple color, then a fixed amount of additional ammonia to provide a slightly alkaline buffered pH. Doing it this way doesn't require me to find any additional chemicals beyond a pool and spa store that carries the sodium thiosulfate rice crystals -- ammonia is cheaply available at the grocery store, and I have a bottle of Kodak Indicator Stop Bath concentrate that, at 1+63 dilution for stop bath that's reusable for a longish time, is likely a ten year supply. This amounts to making a near-neutral ammonium acetate solution, with an indicator to assure it isn't significantly acidic.

I'd just use ammonia directly (3% ammonium hydroxide solution, it shouldn't be hard to figure the molar equivalent to fully react with the sodium thiosulfate) but I'm concerned about making the fixer too alkaline and winding up with a strong ammonia outgas, which is much worse for the lungs and throat than acetic acid vapor from stop bath. I worked (briefly) in a blueprint shop some years ago -- my throat was raw most of the time from the tiny trace amounts of anhydrous ammonia that leaked from the machines; I don't want that in my darkroom.

The advantage of this, in my eyes, is that I can one-shot this -- mix it just before use, dispense with stop bath, and then put the once-used fixer down the drain (the silver from a single roll of film isn't significant, unlike the load in exhausted fixer after long reuse) -- and still avoid shocking soft emulsion films by going from alkali to acid (which is thought to cause most of the complaints about emulsion defects with some films like J&C Pro 100).

 

[Kirk Keyes]

Ole, my thought was to use Indicator Stop Bath to titrate with the ammonia -- add ammonia until the mixture changes to the "exhausted" purple color, then a fixed amount of additional ammonia to provide a slightly alkaline buffered pH.

Donald - get some phenolphthalein indicator - it goes from clear below about pH 8 to pink above. Add whatever amount of ammonia you want and then add acid until the phenolphthalein goes clear. This will get you in the pH 7 to 8 range.

 

[Tom Hoskinson]

IMO that's a lot of fiddling to get to the same place that Ole gets with Sodium Thiosufate, Ammonium Chloride and water.

 

[rjr]

Kirk,

a "kitchen indicator" to check the pH once in a while is the juice of red cabbage - the color change will state the pH range pretty clearly and fast, see the first picture at Dead Link Removed.

 

[Tom Hoskinson]

You can also buffer your Neutral Fixer as Suzuki (Chemistry Recipes) does. I also periodically check my fixer pH with a meter.

 

[roy]

Any input from UK photographers on this topic with sources of products ?

 

[Tom Hoskinson]

I'm not from the UK, but both Ilford and Agfa non-hardening rapid fixes have worked fine for me.

 

[Kirk Keyes]

a "kitchen indicator" to check the pH once in a while is the juice of red cabbage

RJR - yes, I've used red cabbage juice myself too. It is really easy to make, and has a very wide range of colors. The nice thing about phenolphthalein is that it changes color right at the point that one would most likely want for a fixer - just around pH 8. And there should be less question about if you got the endpoint right compared with the cabbage juice. With the phenolphthein, it is pink or clear on one side or the other of pH 8. And it should be not too hard to purchase.

 

[Donald Qualls]

OTOH, phenolphthalein may be a "regulated substance" these days, since they pulled it from the laxative market after finding out it was carcinogenic (if you used it, as a laxative, every day for about twenty years, I think). And again, it's still one more chemical to source; I'm reasonably sure I won't be able to get it from the local pharmacy, and if I were interested in buying the chemicals from a chemical dealer, I'd just get ammonium chloride and be done with it, or buy TF-4 from Formulary.

Red cabbage juice is litmus -- that is, litmus indicator is made from red cabbage. As suggested, though, while it's nice for getting a quick and dirty indication of "acid or base" the change is too gradual to use for an end point. And of course the indicator in stop bath changes color at a distinctly acidic pH (about 5.8, IIRC), which is inconvenient if you want to be slightly alkaline. I suppose I could get a pH test kit at the same pool/spa outlet that will presumably supply the hypo crystals, but then I'm paying for someone to package it up so a pool owner who knows nothing at all about chemistry can keep his pool comfortable.

Part of the point, for me, is establishing the ability to keep this stuff up after the analog photo industry as we know it is gone -- but then if I'm making modern Daguerreotypes on silvered glass, and developing them in vitamin C and coffee (to avoid the mercury), I can fix them just fine in plain hypo (as was done 165 year ago). The other part of the point was to try to figure a simple way to do things with chemicals that aren't labeled as photographic, and automatically marked up 400% as a result...

 

[Tom Hoskinson]

Plain Sodium Thiosufate (Hypo) and Ammonium Chloride are readily available as bulk dry chemicals and they are inexpensive. Ammonium Sulphate is also readily available as a bulk dry chemical and it is inexpensive. The combination of Hypo and either Ammonium Chloride or Ammonium Sulfate will give you a near neutral pH Ammonium Thiosulfate fixer (non-hardening).

If you want to buffer your Ammonium Thiosufate fixer, there are several inexpensive chemicals available including Sodium (or Potassium) Metabisulfite and Sodium Sulfite.

 

[MikeS]

I use Kodak C41 and I add 1oz. of Ammonia (regular household stuff) per liter which brings it up to a pH of 7 when I'm developing with pyro or another staining developer. When I'm using non-staining developers I also use C41 fixer, but instead of the ammonia I add about 10ml of hardener in it . This works fine for me.

 

[mohmad khatab]

Excuse me
Where is the formula Fix (TF-4)?

 

[Rudeofus]

Excuse me
Where is the formula Fix (TF-4)?

It's a proprietary formula.