Washing Kodafix out of Film

[Michel Hardy-Vallée]

I've been reading a couple of threads on fixer and what to do after it, but I haven't found the information I wanted on Kodafix so I'd like to ask for some comments on my current film fixing procedure, and whether it could cause me troubles in the long term storage: I'm doing only 35mm and 120 rollfilm.

* I pre-soak, develop, and stop (water for Efke, Vinegar+H2O for other films) normally
* I use Kodafix fixer 1+3 mostly because I do Efke and APX100 films, which are said to have a more fragile emulsion. I fix for 3 mins, continuous agitation
* I then make a quick water wash (30secs)
* I use Kodak Hypo-Clearing Agent 1+4 from stock solution and agitate continously for 2 minutes
* I wash the film for 10 mins in running water. The use of HCA reduces the washing time from 20mins to 10mins, according to Kodak documentation. My reel goes in a bucket with a hole at the bottom to let the water flow. I also empty and fill the bucket 3-4 times.

I've used this on Efke R25-50, Agfa APX100, Delta 400/3200, Neopan1600, and Tri-X 400TX.

So my questions:

- Do I really need HCA in my situation? Is it making a real difference with film?
- Should I wash more longer because I use a hardening agent?

[Neal]

Dear mhv,

Your process looks good. The only thing I would worry about is the fixing time. For your next roll, check to make sure the film has cleared (no longer milky) at 1-1/2 minutes (because you use 3 minutes as your fixing time). The desired fixing time is double the clearing time so if the film has not cleared, check it occasionally and double the time it takes to clear..

Neal Wydra

[Michel Hardy-Vallée]

Dearest Neal,

Thanks for the clearing help! Would dropping a strip of film in the fixer in broad daylight be significant enough to determine when the emulsion clears?

[photobackpacker]

Yes. Having said that, there is a greater threat to your negatives borne by underfixing than there is over fixing. I use Kodafix for 10 minutes on TMax with absolutely no detrimental impact on the image. 3 minutes sounds a bit light. I would go with at least the recommended 4.

[Neal]

Dear mhv,

Yes. That will work just fine.

Neal Wydra

[Michel Hardy-Vallée]

Thank you all for your suggestions, I'll do my tests this week.

[Michel Hardy-Vallée]

Well, I had some time tonight, so I took a strip of Tri-X 135 (400TX) and soaked it in Kodafix 1+3. After barely a minute my strip was crystal clear. I tried also with Ilford Rapid Fixer and got clearance after the same time.

Kodafix's instructions ask for

* 2-4 minutes for films and plates, with the exception of:
* Panatomic-X: 1-2 minutes
* Tri-X Pan and Tri-X Pan Professional for 5-10 minutes

Ilford's instructions just recommend 2-5 mins for all films. I'll stick to 4 mins for normal films, with either Kodafix or Ilford. I suppose the new Tri-X emulsion reacts the same way as the other ones, but I'll go to 7 minutes for Delta films.

[Neal]

Dear mhv,

Thank you for posting your results. Remember that as you run rolls through that batch of fixer your clearing times will increase.

Neal Wydra

[dancqu]

Remember that as you run rolls through that batch
of fixer your clearing times will increase.
Neal Wydra

That's good advice for those using large tank processing.
Multi-gallon tanks remain full for perhaps months.

For those that use small tanks, and that includes
rotary types, where solutions are over and over into
then out of, one-shot fixer is the way to go.

As an example my last roll of Pan F+ used 20ml of A.
Thiosulfate concentrate in a solution volume of 500ml. Some
what less than 20ml may do. Of course the exact amount
of concentrate needed will depend on the film and it's
exposure. My tests were done with full unexposed
rolls of 120 Pan F+; unexposed is worst case.

S. Thiosulfate, which will store for years, may be used.
In fact the 20ml amount is based on tests done with S. Thio.
If on your shelf use 24 grams penta or 16 grams anhydrous.
It is a slower fix. Again, your film and exposure.

With only A. Thio. concentrate and S. Thio. dry on the
shelf I don't worry if the fix has gone bad, how many rolls
have gone through, how close it is to going bad, or
keeping the bottle clean. Dan

[Michel Hardy-Vallée]

Actually that's an interesting thought: can you dilute normal fixer to the minimal amount required for a film and use it without problems?

For instance, my bottle of Kodafix says that 3.8L of 1+3 diluted solution will fix approximately 120 rolls of 620 film (hello Kodak, time to change the labels!). Provided that I need 500ml to fill my daylight tank for 1 roll of 120, I could fix approximately 15 rolls of film with that amount of fixer at this dilution.

If I reduce the dilution of my fixer by a factor of 15, i.e. moving from 1+3 to 1+45, then I could use ~10-15ml of fixer in 490ml of water to have a one-shot fixer.

Does that make any sense?