Alkaline vs. Acid fixers

[Photo Engineer]

When printing, an acid stop can help with uniformity, especially if you are eager to turn on the lights and see your print.

I use a weak (1% acetic acid) stop before any fix, alkaline or not.

There are acidic and neutral stop baths.

PE

 

[Bruce Osgood]

Another possibly dumb query: is there a non-acidic stop bath? I am aware of 'Ilford wash method' as an alternative to using stop bath chemicals.

Best regards,

Ashfaque

It ain't dumb. The best non-acidic stop bath to be used is water. Especially if you are using TF-4, 5 as your fixer. Some think a stop bath is counter productive when developing a print and the water bath following the development actually enhances the image. But that's just some of us.

 

[Photo Engineer]

The water bath (if you use one) should be running water to prevent seasoning in by the alkali of the developer. So, be careful with this.

PE

 

[ajmiller]

Sorry, but can you explain 'seasoning' - I use a 'static' water stop and wonder what is the effect of this on my prints?
Thanks

The water bath (if you use one) should be running water to prevent seasoning in by the alkali of the developer. So, be careful with this.

PE

 

[Ashfaque]

Thanks a lot everyone for such prompt responses. FYI, I'm asking purely for negative development at the moment.

Michael: Thank you for correcting me.

PE: Much appreciated your tips on using a 1% acitic acid stop bath. I will use that for my negatives from now on. One question, should I worry about any odour?

Bests,

A

 

[Photo Engineer]

Every time you carry a print from the developer to a static water bath, the carryover of developer builds up in the static water bath gradually turning it into a weak developer. This process is called "seasoning". Eventually, development will continue in this water bath and your prints will be different depending on process order.

The way to prevent that from happening is to have a running water rinse after the developer. And, for short development times, you still may get uneven spots on larger prints.

PE

 

[Ashfaque]

When printing, an acid stop can help with uniformity, especially if you are eager to turn on the lights and see your print.

I use a weak (1% acetic acid) stop before any fix, alkaline or not.

There are acidic and neutral stop baths.

PE

I forgot to ask:
(1) Is it possible to use citric acid instead? What would be the dilution ratio with distilled water?
(2) I see only Glacial version on Photo Formulary website. I guess it is a highly concentrated acitic acid. However, reading the MSDS report, I want to avoid buying it as much as possible. Since I'm not a chemistry person, could you suggest a UK/USA based seller of acetic acid?

Bests,

Ashfaque

 

[MattKing]

Kodak Indicator Stop Bath is essentially acetic acid, plus an indicator.

One bottle lasts me a very long time.

I use it at half recommended strength for film, unless I am processing multiple batches, when I use it at recommended strength.

 

[Photo Engineer]

Matt said it all except - yes you can use Citric Acid. I would use it at about 1% as well or at a pH of 4.5 to 6.0.

PE

 

[RalphLambrecht]

I've posted it here on APUG before, but I can't remember where. Since I've also posted more than 1100 other posts here, it's going to be difficult to find as well

Also, I'm at work in the North Sea right now, and I don't have my darkroom notes with me

No, it's not TF-3. It's a simple alkaline sodium thiosulfate formula, modified with a different alkali and addition of ammonium chloride, and a little bit of "tweaking" to keep the smell down...

I use an acid stop(to really stop developmentwhen I want it)for consistency;water stop did not give me any pictorial benefit.
then, I use an slightly acid to neutal pH fixerwithout hardener,followed by HCA and a thorough wash.
the above worksand does consistently so for film and paper.
what other benefit does one need?

 

[StoneNYC]

If the TF-4 type fix is so good, why hasn't someone like kodak or ilford come out with their own? Or have they?

What are the benefits and drawbacks (for negatives and for prints) of either? I've always used ilford stop and ilford rapid fix, I like the idea of a less smelly fix, but since I've almost never had complains with ilford, I'm not sure what reason there is to change? (The NEW OP also said they use ilford so I figure it's relevant).

PS the only issue I have ever had with anything was with FOMA100, where I had some issues with miniature emulsion lifts, I was told that the ilford Stop was too strong for that brand of film and that I should use a water bath stuff to prevent the issue from happening, it did seem to fix the problem, but I only really had a few sheets left so it didn't get extensive testing with the water bath method.

I've also used water bath with some antique films I came across, and by antique I mean just old, like 1950s or so, no insult to anyone who was alive during that era, I'm not calling you antique I promise. I don't even know if I'm doing the waterbath properly, I just pouring some water like I would stop, and add an extra minute so I wash it for two minutes pour it out or in the second thing of water just in case, and then pour that out and then pour in the fix. I always thought that the fix itself would actually stop the development anyway, but it sounds like you're saying that if the water is reused then it could potentially continue to develop in the fixer, which is confusing to me, I must you're saying that this only happens with the TF-4 and that other fixes like the Ilford rapid fix wouldn't have that issue because it is acidic?

Sorry if I'm confused, and thanks for any info.

 

[MattKing]

If the TF-4 type fix is so good, why hasn't someone like kodak or ilford come out with their own? Or have they?

Kodak has - the fixer used for C-41.

It works really well for black and white as well.

See: (there was a url link here which no longer exists)

There are some commercial advantages (price, packaging, capacity) to using the black and white specific products in a commercial black and white operation. Otherwise, I expect that the C-41 fixer would be sold instead for black and white.

 

[MattKing]

If the TF-4 type fix is so good, why hasn't someone like kodak or ilford come out with their own? Or have they?

What are the benefits and drawbacks (for negatives and for prints) of either? I've always used ilford stop and ilford rapid fix, I like the idea of a less smelly fix, but since I've almost never had complains with ilford, I'm not sure what reason there is to change? (The NEW OP also said they use ilford so I figure it's relevant).

PS the only issue I have ever had with anything was with FOMA100, where I had some issues with miniature emulsion lifts, I was told that the ilford Stop was too strong for that brand of film and that I should use a water bath stuff to prevent the issue from happening, it did seem to fix the problem, but I only really had a few sheets left so it didn't get extensive testing with the water bath method.

I've also used water bath with some antique films I came across, and by antique I mean just old, like 1950s or so, no insult to anyone who was alive during that era, I'm not calling you antique I promise. I don't even know if I'm doing the waterbath properly, I just pouring some water like I would stop, and add an extra minute so I wash it for two minutes pour it out or in the second thing of water just in case, and then pour that out and then pour in the fix. I always thought that the fix itself would actually stop the development anyway, but it sounds like you're saying that if the water is reused then it could potentially continue to develop in the fixer, which is confusing to me, I must you're saying that this only happens with the TF-4 and that other fixes like the Ilford rapid fix wouldn't have that issue because it is acidic?

Sorry if I'm confused, and thanks for any info.

The traditional black and white fixers range from being slightly acidic to highly acidic.

The slightly alkaline or neutral fixers (like TF-4) promote quick and efficient washing, which is especially important for FB prints. IIRC, there are also technical issues relating to emulsion swell that I don't understand.

However, if you introduce active developer into an alkaline or neutral ph fixer with your film or paper, then that alkaline or neutral ph environment will permit that developer to continue to develop that film or paper past when you want it to stop. So it becomes quite important that you use, at minimum, a thorough running water rinse or, preferably, an acidic stop bath, to fully stop development and render inactive any developer carried over.

Ilford Rapid Fixer and Ilford Hypam are excellent fixers. So is Kokak Rapid Fix.

 

[Ashfaque]

Matt and P.E.: Thanks again for your helpful posts.

Bests,

Ashfaque

 

[ajmiller]

Apologies OP for clouding the print/ negative thang - but all helpful info nevertheless.
Thanks also from me.

 

[Trask]

After reading all 42 posts in this thread, I come away knowing that TF-4 is an alkaline fixer. I'm impressed that some many other folks know which of the others are alkaline and which are acid, but I can't say that I do. So, is there something I should look for on the bottle or package that would clue me in? Or is there a Massive Fixer Chart somewhere that lists all fixers and their acidity/alkalinity?

I've recently purchased a bottle of TMax Fixer here in Europe -- it works well, it's quick, but whether it's acidic or alkaline...

 

[Thomas Bertilsson]

Ilford Rapid Fixer and Ilford Hypam are excellent fixers. So is Kokak Rapid Fix.

Since I started this thread ten years ago, I figured I should comment on Ilford Hypam, which I have used for about the last ten years or so. It is a close-to neutral pH fixer, which doesn't rob pyro developers of their stain. I've used it with Pyrocat and PMK without losing stain. It's a great economical fixer that is available at my local photo supplier. I'll keep using it as long as I can.

I also use an acidic stop bath, namely Sprint stop bath, because it is near odorless and also has an indicator when the pH goes off. I recommend its use because you know for certain that the paper or film has been properly neutralized of developer action, and uniformly so, before the material goes into the fixer.

 

[Ashfaque]

Trask has asked a very pertinent question, that Michael has answered with lots of useful information. Very useful for a new starter like me. They're going into my notebook. Thanks a lot, gents.

Ashfaque

 

[Photo Engineer]

The info above on TF3, 4 and 5 is correct as is the suggestion that a mildly acidic stop be used or a running water rinse be used after development. All of this will "encourage" uniformity in your results.

There is no massive chart on fixers. The data on the TF series is on the bottle and in the on-line instructions.

Kodak did make a pH 9 rapid hardening fix for C22 but stopped making it when C41 came out. The C41 fix is "universal" and with the proper dilution is a pH 6.5 (about) mildly acidic rapid fixer for all products if you use the proper dilution. It can even be used with the "red" part of the RA4 blix if the colorless part goes bad. So, treat it as a good friend. It is one.

PE

 

[ericdan]

When printing, an acid stop can help with uniformity, especially if you are eager to turn on the lights and see your print.

I use a weak (1% acetic acid) stop before any fix, alkaline or not.

There are acidic and neutral stop baths.

PE

to stop development I understand, but won't the developer traces on the paper or film start developing again in the alkaline fixer unless you wash them off after the stop bath.

 

[RauschenOderKorn]

to stop development I understand, but won't the developer traces on the paper or film start developing again in the alkaline fixer unless you wash them off after the stop bath.

In my experience: If you stop properly and work in the red/dark, there´s no problem at all. Fixing paper and film takes a very short time (at least with Moersch Alkaline Fixer 1+9), and even if redevelopment starts, the fixer acts extremely fast.

There is a thread going on right now about fixing film by inspection, i.e. turning on white light after the stop bath and before the fixer. As it seems, this does not work for film and alkaline fixer, but I´d say that procedure is particular.

 

[RauschenOderKorn]

You only need 2 chemicals: developoer and fixer. That's it.

How do you then stop development? Or do you adjust times for prolonged development in the fixer?

In my experience, a proper stop with alkaline fixer is essential, for instance PE´s recommendation.

 

[ericdan]

In my experience: If you stop properly and work in the red/dark, there´s no problem at all. Fixing paper and film takes a very short time (at least with Moersch Alkaline Fixer 1+9), and even if redevelopment starts, the fixer acts extremely fast.

There is a thread going on right now about fixing film by inspection, i.e. turning on white light after the stop bath and before the fixer. As it seems, this does not work for film and alkaline fixer, but I´d say that procedure is particular.

Interesting. I should measure how long Moersch ATS takes to fix. I use 1 + 5 dilution for film and paper.
I quickly rinse after the stop bath before the fixer, but that quick rinse doesn't seem to be enough to get rid of the remaining developer.
Fixing by inspection still develops almost the entire film.

 

[RauschenOderKorn]

With the 1+9 Dilution, I have had clearing times between 30 s and 45 s @ 21-22 C depending on the film and how spent the fixer was. I have measured these clearing times on HP5+ (120), Rollei RPX 400 (120), Rollei RPX 100 (135), Agfa APX 400 (new Emulsion 135) and fomapan 100 and 400 (120 both) and Rerapan 100 (127). [I have used way too many different types of film, lately, what a mess]. Developer has been Microphen or Perceptol.

As I do not expose the film before / during fixing, the development might restart and last for a few seconds again. Compared to the actual development time, that is negligible and I am not able to see any visible effect. Furthermore, you should consider the pH of the ATS: 7,8 according to the MSDS, that is "almost neutral". Moersch Eco film developer has a pH 10,65 for instance, or Rollei RPX-D pH 10,45, ID-11 comes in at pH 8,7 and Kodak HC-110 at pH 9,0.

 

[Bruce Osgood]

I haven't used a Stop Bath in 5 years. I use running water to "neutralize" the development process and the soft friction to seperate developer from the paper. I follow that cleansing with TF-4 fixing. I've not seen any drawbacks.