Alkaline Hypo

Questions on fixers for both film and paper

Moderator: Black & White Moderators

Post Reply
tim.bowman
Posts: 43
Joined: Mon Nov 07, 2016 8:55 am
Location: Winston-Salem, NC, USA
Contact:

Alkaline Hypo

Post by tim.bowman »

Hello all, this is my first post to the forum.



I am a recent convert to the all-alkaline printing process and am hoping those of you who are more experienced with it can help me verify my process.



I have been using TF-2 instead of a rapid alkaline formula because, well, I have a stock of sodium thiosulfate and don't have any ammonium thiosulfate. I take the Kodak approach and use a first and second fixing bath. My prints spend five minutes in the first and five in the second bath (achieving Mr. Anchell's recommended 10 minutes fixing time) before going into the holding tray. At the end of my session, they get washed in warm water for 30 minutes.



Keeping my entire print process alkaline is pleasant because my darkroom doesn't stink like bisulfite or acetic acid and I don't need a hypo-clear. But I have only been doing this for a few months. The prints I made 20 years ago using acid fix are all fine. The prints I'm making with alkaline fix seem fine, but I have no idea how they'll be in 20 years. Can anyone here offer some guidance?
User avatar
sanchell
Posts: 226
Joined: Mon Feb 13, 2012 8:47 am
Location: Oregon
Contact:

Alkaline Hypo

Post by sanchell »

I use two alkaline baths of 2 minutes each. The majority of fixing takes place in the first bath and any residual argentothiosulfate crystals that remain, if any, are dissolved in the second bath. I have been using this method since about 1989 and I have yet to see any deterioration in prints that have been properly stored in archival boxes.



Beyond that, my best suggestion is to hang around for about 20 or 30 years then post the results on this site. :)
Do it in the Dark,



Steve Anchell
tim.bowman
Posts: 43
Joined: Mon Nov 07, 2016 8:55 am
Location: Winston-Salem, NC, USA
Contact:

Alkaline Hypo

Post by tim.bowman »

Right then, 20 years it is. Thank you for replying, Mr. Anchell. I assume you're using an ammonium thiosulfate fix, is that correct?



Let me also add a grateful side note... Thank you for writing the cookbook. Knowing what's in my soup gives me increased control over my process and also frees me from relying on secret commercial formulas. What a gift.
User avatar
sanchell
Posts: 226
Joined: Mon Feb 13, 2012 8:47 am
Location: Oregon
Contact:

Alkaline Hypo

Post by sanchell »

Thank you for the kind words.



Yes. I am using AT. However, Bill Troop and I have been working on the 2nd ed. of The Film Developing Cookbook and he may have some new ideas about ST vs. AT.
Do it in the Dark,



Steve Anchell
User avatar
perfesserkev
Posts: 34
Joined: Sat Nov 12, 2016 9:05 am
Location: Indianapolis
Contact:

Alkaline Hypo

Post by perfesserkev »

Bill Troop and I have been working on the 2nd ed. of The Film Developing Cookbook


That's a cool bit of news! ETA?
"You compose, you decompose." -- Ernst Haas
User avatar
sanchell
Posts: 226
Joined: Mon Feb 13, 2012 8:47 am
Location: Oregon
Contact:

Alkaline Hypo

Post by sanchell »

Should be out late 2017. Waiting on Bill's research.
Do it in the Dark,



Steve Anchell
tim.bowman
Posts: 43
Joined: Mon Nov 07, 2016 8:55 am
Location: Winston-Salem, NC, USA
Contact:

Alkaline Hypo

Post by tim.bowman »

That is great news. I'm looking forward to seeing the 2nd edition.
andynguyen
Posts: 37
Joined: Wed Feb 24, 2016 8:45 pm

Alkaline Hypo

Post by andynguyen »

Steve, i'm gonna pick your brain here a lil:



I read somewhere that fixers were acidic because when the acid was necessary for the alum hardener. Otherwise it can be omitted. So recently, in an effort to make a fixer that:



- is non-acidic

- rapid, but without using AT (coz i cant source for that locally)



I've mixed:



200-250gr sodium hypo

50-75gr soldium sulfite

50-75gr ammonium chloride (to simulate the AT)



Initially i threw in some metaborate (borax + NaOH, mixed to correct ratio), following your formula of TF-2. It ends up stinking of ammonia. I guess the pH kinda shot too high so the NH3 refused to stay in solution.



So for the next mix, i just used borax (2gr/L). The smell seems to reduce. & film clears in 30s or so, so that's kinda nice.



My question is: I kept that bottle for a week & now it smells ammonia somewhat. Would omission of the borax help? Or should i make it acidic (with citric) to keep the ammonium from escaping? I heard that in acidic environment sulfurisation occurs more quickly, so I think I've gotta strike a balance on pH?



P/s: I've also laid hands on some Kodak C-41 fixer. seems to be the best thing since sliced bread: neutral pH, doesnt go bad with time, no sulfurization, & super rapid. I wonder what they put in it....
User avatar
sanchell
Posts: 226
Joined: Mon Feb 13, 2012 8:47 am
Location: Oregon
Contact:

Alkaline Hypo

Post by sanchell »

Andy, you are to be lauded for your efforts. What you are asking is more in the line of Bill Troop, who formulated the TF line of fixers (Troop Fixers). I'll ask him to take a look at this.
Do it in the Dark,



Steve Anchell
Bill Troop
Posts: 8
Joined: Wed Mar 09, 2016 2:06 pm

Alkaline Hypo

Post by Bill Troop »

Hi Andy, you raise a number of issues. First of all, if an alkaline fixer is going to be used with open trays for prints or sheet films, then it is desirable to control the pH close to neutral to avoid evolving ammonia. So I'd say your main mistake was thinking you had to have a high pH. You can, but it isn't necessary. I would say that if you just used ammonium chloride, sodium thiosulfate and sodium sulfate, you would have something close to ideal. Try to keep the pH a little above neutral and most definitely above 6.5. I would also prefer to use the amounts used in Kodak F-8: sodium thiosulfate pentahydrate 360 g, sodium sulfite anhy 15 g, ammonium chloride 50 g OR ammonium sulfate 60 g. (sulfate is kinder to some forms of stainless steel). These proportions do not result in complete conversion of sodium to ammonium thiosulfate, and the speed increase is about 2x rather than 4x. But there are a lot of reasons to do it the Kodak (or to be more specific, the Harold Russell) way. There will be a LOT of discussion of this in FDC2. These three chemicals may provide the pH you require, or you may need to balance it out with a little more alkali, but not nearly as much as you have been using. Decide on your target pH and then measure carefully until you get there. If you can't afford a good pH meter, use narrow range indicator papers, and it's a good idea to use both to cross check. At the level of sophistication you're at, you should take pH seriously.



Second, regarding C-41 fixer, the secret is that it combines ammonium thiocyanate with ammonium thiosulfate, much like Ron Mowrey's Superfix formula. Thiocyanate softens gelatin and must be used with caution. It is fine with the latest films from the largest manufacturers but should not be used when the films have not been super-hardened (third generation hardening i.e. with BVSM or equivalent). It should not be used with paper in my view, because it will make the material too fragile. Another point is that archival stability questions arise with thiocyanate that have never been fully resolved. It may provide some protective effect against atmospheric pollutants and aging under some circumstances, and under other circumstances, may not and may even cause problems. C-41 fixer is tempting to use when it is cheap and everything else you can find is expensive, but personally, I would prefer not to use it for black and white materials, which it was never intended for.



On balance, I believe the approach you have taken, mixing sodium thiosulfate (which is always cheap) with ammonia ion, is the best solution for economizing when ammonium thiosulfate is expensive in your area.



You are articulating concerns that have been very much on my mind. There will be a lot on these issues in the new FDC. Thank you. It's good to know I'm not the only one worried about this stuff. - - Bill
User avatar
sanchell
Posts: 226
Joined: Mon Feb 13, 2012 8:47 am
Location: Oregon
Contact:

Alkaline Hypo

Post by sanchell »

In case you haven't already heard, Bill is working hard on the second edition of The Film Developing Cookbook. The first edition was a complete collaboration between Bill and me. The second is almost entirely Bill's, with a slight bit of input by me (just enough to keep my name on the cover :) ).



Bill is taking his time and being very careful to fact check, and double check everything, so it will be well worth the wait.



Both Bill and I will provide occasional updates as the project moves forward.
Do it in the Dark,



Steve Anchell
andynguyen
Posts: 37
Joined: Wed Feb 24, 2016 8:45 pm

Alkaline Hypo

Post by andynguyen »

Thank you both, Steve & Bill, for your replies. Certainly I'm enlightened quite a bit. I didnt know TF stands for Troop Fixers.



I do have a pH meter, though I've not been checking & recording as often as I should. I will try to keep a log from now.



I'm scaling up the operation (coz we're trying to open our darkroom for public access), I'm thinking of making a fixer concentrate based on that formula (with some pH balancing). & I want to make it twice to 3 times more concentrated. I've checked out the solubility of the chemicals. It seems to be in orders: 700g of Hypo can go into 1L, so that sounds like i can make a solution to be diluted 1+2 for use (if i use 600gr). Other chemicals will scale up similarly. I wonder if that'd have any downside compared to mixing working solution.



I will try that & update.
Bill Troop
Posts: 8
Joined: Wed Mar 09, 2016 2:06 pm

Alkaline Hypo

Post by Bill Troop »

I would be cautious about the scaling up you're contemplating. As far as I know, concentrating sodium thiosulfate has never been attempted or recommended in the entire photographic literature. When you're trying to do something like that, there is usually some gotcha. The only very slight scaling up I can find is where 1 part of Kodak Hardener F-5s is added to 4 parts of 30% sodium thiosulfate solution. Like you, I can't see any reason why, looking at the solubilities, what you propose shouldn't work, but I still wouldn't do it. It's easy enough to mix up conventionally. I will keep this issue in mind though. - -
Post Reply