C-41 Fixer for B&W?

[Robert Kerwin]

I've run across several posts indicating that people have used C-41 fixer for B&W. My understanding is that it is a rapid fix with a slightly acidic pH. I'm also considering Formulary TF-4, which I know has rave reviews, but I'm a little put off by the price (about 3X the cost of C-41 fixer).

Has anyone used C-41 fixer for B&W? What fixing times are you getting for film and paper? How does it compare to other rapid fixers in terms of wash times for FB papers?

Thanks,
Robert

[htmlguru4242]

It works; I'm not sure about times, I've used it once with about regular fixing times (5 min. for film). I'm not so sure why you'd want to do this, as B&W fixer can easily be obtained on the cheap, unless you have some. I'd reccomend experimenting to see how it goes ...

[Peter De Smidt]

I buy 5 liter jugs of fix for minilabs, and I dilute it 1 +4 for both film and paper. It works very well, and it's cheap! Yes, it's nothing more than rapid fix. As far as I can tell, it's equivalent to Kodak rapid fix without the sulfuric acid added. For FB prints I use a two bath system, with 1 minute in each bath. For film, it depends. I usually fix T-grain films for 7 minutes with continuous agitation.

[eumenius]

I use it all the way for all my BW fixing purposes, dilute it 1+7 with water (I find it too strong when diluted 1+4), and I fix about three minutes. A clearing time plus the same amount of time, an usual rule. I always use an 2% acetic acid stop bath before fixer, just to contaminate it less and to stop the development - you see, C41 fixer is ALKALINE.

[Photo Engineer]

I use it all the way for all my BW fixing purposes, dilute it 1+7 with water (I find it too strong when diluted 1+4), and I fix about three minutes. A clearing time plus the same amount of time, an usual rule. I always use an 2% acetic acid stop bath before fixer, just to contaminate it less and to stop the development - you see, C41 fixer is ALKALINE.

Properly compounded C41 fix is pH ~6.5. The correct range is about 6.3 - 6.8 for proper activity. (20 deg C)

There are two forms. C41 and the RA version which contains Ammonium Thiocyanate. It is much faster than the version without SCN.

PE

[john_s]

I've been using Agfa FX-Universal for film and paper. Its pH is about 7.5. Now that Agfa products are not available here (Australia) I will need to look at Kodak or Fuji C-41 fixers. Their pH tend to be a little on the acidic side, for example Kodak Flexicolor Fixer is pH=6.2 (stated in MSDS, so I suppose that is for the undiluted stock).

I found that FX-Universal was not quite as fast at fixing some films as normal acidic rapid fixer, but still quite ok. For paper I use 2-bath and have never tested for capacity or fixing time. I have probably over fixed at times, but no apparent problems. I don't risk allowing fixer to become near capacity. The low price made frequent replenishment/replacement not too expensive. Odour is minimal, but don't worry, your darkroom still ends up smelling like a darkroom!

I will probably try the Kodak product, but with the price of sodium thiosulphate in 25kg bags quite low, I just might make up something like Ole's fixer at about neutral pH. I would just use hypo, sodium sulphite and ammonium chloride.

[john_s]

Properly compounded C41 fix is pH ~6.5. The correct range is about 6.3 - 6.8 for proper activity. (20 deg C)

There are two forms. C41 and the RA version which contains Ammonium Thiocyanate. It is much faster than the version without SCN.

PE

The one with thiocyanate is much more expensive, I think (maybe 3x the price).

[Gerald Koch]

Properly compounded C41 fix is pH ~6.5. The correct range is about 6.3 - 6.8 for proper activity. (20 deg C)

There are two forms. C41 and the RA version which contains Ammonium Thiocyanate. It is much faster than the version without SCN.

PE

Thiocyanates can cause softening of photographic emulsons. I would not use the RA version.

[fschifano]

I will probably try the Kodak product, but with the price of sodium thiosulphate in 25kg bags quite low, I just might make up something like Ole's fixer at about neutral pH. I would just use hypo, sodium sulphite and ammonium chloride.

It might be cheaper to use Kodak's Flexicolor fixer. From B&H and Adorama you can get enough concentrate to make 5 gallons for about $8 US without the fuss and bother of shipping and storing 25kg. of sodium thoisulfate. The stuff works and works well.

[Photo Engineer]

Thiocyanates can cause softening of photographic emulsons. I would not use the RA version.

Yes, they do, that is one of the reasons why fixing is so fast when they are used. But it would be more appropriate to say that they cause more swell rather than more softening if used properly. If used improperly both can take place.

However, in spite of this they can be very effective up to 100 deg F (~40 deg C), and they don't harm color film emulsions.

After all, that is the C41 process temperature.

You will have to be careful with B&W emulsions.

PE