400Tmax and optimum fixing

[Bruce Watson]

I'm running 400Tmax and would like to optimize fixing and washing. I nailed down developing via the Zone System. But there doesn't seem to be anything like that for the rest of the process.

1) Are there any tests (not rules of thumb like "fixing for twice the time it takes to clear") I can run to determine an optimum fixing time -- like a silver halide test to see if there's any remaining in the film?

2) What's the best test for whether or not the film is properly washed? Is there a good residual hypo test that people think is reliable? I'm asking this because I live in an area that periodically has water restrictions so I'd like to wash sufficiently but not excessively - not wastefully.

I'm using a Jobo and processing in a 3010 tank, all chemistry used one-shot including Kodak Rapid Fixer (without the hardener).

I asked these questions on APUG and got little response. Anyone here want to give it a shot?

[Ed Richards]

I would use Kodak's recommendation on fixing, they have pretty good chemists and this is a chemist's problem.

I think washing has been mostly mythology. First, isn't there some literature that indicates that your goal is not perfect removal of hypo, that a little residual stablizes the film?

Second, the big issue with washing is not how many rinses, but how throughly you remove the water in each rinse. (Think of it as an engineering problem - workout residual with 5% remaining in the tank versus 1% remaining for 4 rinse cycles.) Tmax is on a non-absorbant base, and is a very thin film emulsion. You do not have to soak stuff out of the base, just out of that really thin film.

I do four rinses in my expert drums, using 350ml for each rinse. I rotate 2-3 minutes per rinse. The last rinse is distilled water, and then I treat with photoflow in distilled water. I use a bessler base and lift the drum off and drain it as much as I can. I do not know how completely you can get the Jobo to empty the drum, but you could test it. If it is not getting almost all of the water out, washing will be much less efficient, requiring a couple more cycles.

[ic-racer]

You certainly can and should test for correctly washed and fixed prints.

For fixing you can use the Kodak ST-1 test for residual silver.
For washing you can use the Kodak HT-2 test.

Light Impressions used to sell a set of 'testing pens' that would cause color changes if the materials tested were not properly processed.

http://unblinkingeye.com/Articles/Archival/archival.html

[John Bowen]

I use the formulary TF-4. I fix Tmax 400 for 6 minutes, then wash. That is sufficient to remove the pink cast on the negatives.

[Ron Marshall]

I'm sure you've seen Kodak's recommendations for fixing and washing. They probably are conservative values:

http://www.kodak.com/global/plugins/acrobat/en/professional/products/films/bw/processChartLo.pdf?id=0.2.26.14.17.30.3&lc=en

[cjbroadbent]

Having had problems fixing tmax, which exhausted the small volume of fix required for tubes, I now fix twice with unaltered diluition.

[ic-racer]

You certainly can and should test for correctly washed and fixed prints.

For fixing you can use the Kodak ST-1 test for residual silver.
For washing you can use the Kodak HT-2 test.

Light Impressions used to sell a set of 'testing pens' that would cause color changes if the materials tested were not properly processed.

http://unblinkingeye.com/Articles/Archival/archival.html

I know you asked about film, and these tests are appropriate for film and paper.

[Pat Kearns]

Years ago I was told by a Kodak rep that frequent agitation is required with the Tmax films because they exhaust the fixer quickly. I fix my Tmax for 7 minutes using a beseler rotary drum with constant agitation on the motor base. For my roll films agitate by inversion continuosly for the first 30 seconds, then invert every 30 seconds afterwards for 7 minutes. A purple cast is left on the film if it isn't fixed long enough. If that happens refix it.

[Andrew O'Neill]

You will notice that fixers exhaust quicker with tmax films...at least that has been my experience...especially if you use a water stop bath. I prefer a mildly acidic stop bath (usually a tea spoon of citric acid to 1 litre of water...I use it until the film feels slimy). Basically I fix until there is no pink. This is gone pretty quickly if I've develop in xtol...probably the higher sodium sulfite content in xtol is more effective at removing the pink cast...than if I developed in pyrocat-hd, which has very little sodium sulfite. I fix TMY for 5 minutes. I should add that I use Ilford Rapid fix and sometimes homemade TF-3. I should also add that all films go in a water bath prior to development. As well as promoting even development, it also serves to remove that pesky blue backing strip on the back of TMY. I usually develop in tubes.
I give a quick bath in HCA bath (I feel is a very important step!) and then wash by changing the water in a tray, 10 times (agitate each time for one minute by cycling through the stack if you have many sheets...since I use a non-hardening fix, I am extremely careful!! I usually don't do more than 4 sheets at a time).
I have found this method to be a very effective way of washing...it's also a great way to conserve water.
The important thing is to get into a routine and stick to it.

[CG]

... isn't there some literature that indicates that your goal is not perfect removal of hypo, that a little residual stablizes the film? ...

The latest I've seen indicates that a minute residual trace of hypo benefits longevity. BUT, that research was on some other silver based product than the films and papers we are likely to be using, so at the time I read it it was yet a tentative conclusion. Evidently the use of true "hypo eliminators" (as opposed to hypo clear and other wash aids) has been deemed to probably be a bad idea. Please note that despite popular mixing of the names, the sulfite based wash aids like Kodak Hypo Clearing Agent are NOT true hypo eliminators! True hypo eliminators are stronger stuff. They destroy hypo, not just make it more easily washed from an emulsion.

Near the bottom of this page: http://wiki.silvergrain.org/wiki/Washing_aid there is a paragraph entitled: "Benefits of residual thiosulfate". The writing there is more definitive than the research I recall reading, but the general drift is the same.

C