Use of highly diluted (34g/L or less) plain fixer with film as one-shot

[Raghu Kuvempunagar]

If one is travelling and can't carry liquid chemicals but want to process film in the hotel bathroom, Caffenol and OP's one shot fixer can be a lifesaver even if not optimal.

 

[npl]

If one is travelling and can't carry liquid chemicals but want to process film in the hotel bathroom, Caffenol and OP's one shot fixer can be a lifesaver even if not optimal.

Travelling with a couple of Tetenal Superfix tablets would be ideal for that case : https://www.tetenal.fr/tetenal-chimie-superfix-tabs-fixateur-film-et-papier-c2x35872401.

Stocks won't last forever but look like I could order some right now from a french online shop.

Tetenal also made a B&W film developer in tablets form : https://www.tetenal.fr/tetenal-chimie-parvofin-tabs-revelateur-film-n-b-parties-1-et-2-c2x35872400

Were they the only one doing photo chems in solid form like this ? would be great to have more choice, especially as CT scanner will be soon deployed worldwide and processing before taking off could get more and more relevant.

 

[Alan Townsend]

Here is my recommendation, assuming your place of residence is correctly shown in your profile: take a look at Photo Formulary or Freestyle, both have offerings substantially below the price point you listed.

Thanks for the information. B+H is much closer to me, so shipping is much less from there. I'm not a poor boy who needs economic help, I enjoy experimenting and enjoy doing things my way instead of what everybody else is doing. Last winter, I mixed up sone TF2 and used with print papers and films, but myself I rarely do traditional printing. It had very poor shelf life in a full bottle. If I started using that, it would eat up my approx. 22 lbs. of hypo that I have left at about 4 times my current rate. I do alt process printing from enlarged negatives, and use a fair amount of ortho litho film for that. That film clears in less than 30 seconds in my dulute fixer. Also Xray film that I have that I plan on using much more in the near future, also clears very quickly. I talk about the economics for the sake of other people who are less wealthy. Mostly young people. I have a lifetime supply of hypo on the shelf.

If you get a neutral fixer (typically labeled "neutral" or "odorless"), then both concentrate and working solutions will last for well over a year. I still use neutral rapid fixer mixed from concentrate canisters purchased in 2020, and they were sold through a fire sale like offer, which means they have probably spent some time in the store before I bought them. Unlike acidic fixer these will not sulfur out.

Good for you.

 

[beemermark]

Have to say I've never heard of diluting fixer. Not sure why you would do that but hey. Interesting discussion. I use Legacy Pro B&W Powder Hardening Fixer (To Make 1 gal) for ~10. I always dump the fixer from tank back into the gallon. I use a hypo check, like Arista Premium Hypo Check every once in a great while to check for exhaustion. I have two bottles of the check (by mistake) and can't remember what century I bought them. And spend $49 at BHPhotoVideo and shipping is free. get their credit card and they pay the sales tax. So messing around diluting fixer isn't something I'd bother with.

 

[Alan Townsend]

Once again, it's fine to state how you do something that you believe works well for you you, but it's irresponsible to try to use that anecdote against the recommendations of manufacturers and contradict what is essentially established knowledge.

Plain fixer at higher dilutions hasn't been studied because there's no reason to study it. I have studied and used it over the last years and find it interesting. It keeps much better at lower dilutions than it does at higher dilutions. My 34g/L solutions keeps for two days in partially full stoppered bottles. The standard 240g/L hypo dilutions don't even keep overnight. It's narrow minded and a bit absurd to accuse me of being irresponsible.

If @Rudeofus says that your fixer dilution will almost certainly not completely fix your film, his opinion has easily as much weight as yours. You're not offering any proof of anything other than "Looks good to me" so there is no substantial ground for argument.

Well, there's little details like 240g/L plain fixer have historically reported capacities of a square inch of film per 100mg of hypo. At my dilution, I'm almost double that amount.

Personally, I say if you can get what you want soaking your film in sea water, go for it. Has nothing to do with me. And chances are your negatives don't need to last longer than it takes to scan them or make a couple of prints - almost none do. So go ahead with the weak fix method. But don't tell others to do it unless you can objectively prove it does always completely fix the film.

If this topic has nothing to do with you, why are you insulting me and my work? Just negative by nature? You are the one telling people what to do, not me. I'm simply reporting good news and don't need to prove anything. All you need is some common sense and the desire to explore.

 

[Raghu Kuvempunagar]

Travelling with a couple of Tetenal Superfix tablets would be ideal for that case : https://www.tetenal.fr/tetenal-chimie-superfix-tabs-fixateur-film-et-papier-c2x35872401.

Tetenal Tablets are a great idea if you can get/afford them.

Just curious. How many grams of Thiosulphate does a Superfix tablet contain?

 

[koraks]

It's messing around.

"desire to explore"

Sometimes, the latter may seem like the former depending on one's perspective. I see people do things all the time that I would qualify as 'messing around', but they are simply looking for something different than I am. Let's take this into account. And let's perhaps also acknowledge that we sometimes put somewhat fancy words to fairly mundane activities. When I embark on a culinary journey into uncharted sensory territory, in reality I'm just going to cook that aubergine in a way that my wife hopefully doesn't find godawful.

 

[Animalcito]

A good resource on the chemistry behind fixation can be found in "Modern Photographic Processing, Volume 1" by Grant Haist.
On page 579 there is a graph showing studies on fixation times from the 1930 with thiosulfate concentrations ranging from 50 g/l to 600 g/l. The logic behind the two times of clearing time rule of thumb is explained and that there is a difference if the clearing time is tested on a dry or wet film.

 

[Don_ih]

cook that aubergine

I'll concede that photography inspires a lot of exploration, particularly when you start experimenting with chemicals in the darkroom. But some things are more like whether or not you should fully cook chicken than how hard you like your egg yolks.

 

[MattKing]

A good resource on the chemistry behind fixation can be found in "Modern Photographic Processing, Volume 1" by Grant Haist.
On page 579 there is a graph showing studies on fixation times from the 1930 with thiosulfate concentrations ranging from 50 g/l to 600 g/l. The logic behind the two times of clearing time rule of thumb is explained and that there is a difference if the clearing time is tested on a dry or wet film.

Thanks for the reference to Haist. Like so many of these things, I think the controversy in this thread is more to do with the rationale behind what appears to work for the OP than the quality of the results obtained by the OP.
In general we would ask the membership to be constructive in any critical analysis they may engage in - both in respect to the results that people report and their understanding of how and why they believe they obtained those results.
I would refer to many posts over the years from two formerly active members: Simon Galley of Ilford/Harman who when asked about his choice of routine when fixing film stated that he used the method he used because that was he had always done, and Photo Engineer/Ron Mowrey of Kodak who said innumerable times that even if he wouldn’t recommend a particular technique that if it worked for someone then it was fine.

 

[Doremus Scudder]

gealto2,

I'm all for finding more practical and economical ways to use chemicals, especially fixer.

That said, unless you've done rigorous testing of your methods for residual silver (ST-1 or the Kodak Rapid Selenium Toner tests), you really have no good idea if your method is fixing your materials adequately or not, or to what standard of permanence.

I routinely take underfixed and underwashed test prints, dry them and hang them on my viewing board, sometimes for months. They don't discolor at all in that time, but I certainly don't think that they are anywhere near adequately fixed or washed.

Your prints might last years even, and that might be good enough for your purposes. However, if we want to get the greatest longevity from our photographic materials, we should be processing them to the highest standards possible. Testing that, with both the ST-1 (or selenium) tests for residual silver and the HT-2 test for residual thiosulfates (even though both these tests are not really laboratory quality), should give you some idea if you're achieving that goal.

If you haven't tested, you just don't know.

Best,

Doremus

 

[Alan Townsend]

If you haven't tested, you just don't know.

Best,

Doremus

The question is "do I really want to know?" The honest answer is not really. I don't make traditional silver gelatin prints hardly ever. The main reason I like my weak fix is due to my workflow, which is likely different from most. Since I have about a pound of sodium sulfide on my shelf, I will likely do that test when in the mood.

 

[Mr Bill]

... and Photo Engineer/Ron Mowrey of Kodak who said innumerable times that even if he wouldn’t recommend a particular technique that if it worked for someone then it was fine.

I suspect that he often was either being polite or wasn't ready to give up his time in something of a pointless argument/discussion. People tend to do what they wanna do; trying to show them a different side of the issue sometimes doesn't work cuz they're not ready to listen. It's sort of an uphill battle trying to convince them otherwise. So saying "if it works for you..." can be a graceful way to leave the argument; no one goes away mad (angry).

 

[Raghu Kuvempunagar]

Tetenal Tablets are a great idea if you can get/afford them.

Just curious. How many grams of Thiosulphate does a Superfix tablet contain?

I couldn't find exact weight of each fixer tablet, but this page gives some idea:

Tetenal Superfix Fixer Tabs - CLOSEOUT

Tetenal Superfix Fixer Tabs - CLOSEOUT - ***CLOSEOUT: Limited to stock on hand.***TETENAL Superfix Tabs for many decades has stood for the safe and fast fixing of films and papers. Technically updated again and again and adapted to the available materials,…

www.freestylephoto.com

"Packaging = 750ml plastic jar approximately 4.25" wide, 4.3125" tall, 2 pounds"

Twenty tablets + packaging weigh about 900 g. So each tablet is not more than 45 g in weight. The weight of Thiosulphate in each fixer tablet is not way off from OP's. Concentration is different obviously and Tetenal might have used fixer accelerators unlike OP.

 

[dokko]

attached the german instruction manual of the Superfix tabs.
It lists one tab as 20g, and the instructions say you should use 7 tabs for 1050ml of solution, so that's 133g/liter.

it specially mentions:
"Die Ansätze dürfen nicht über die vorgegebenen Mengen hinaus verdünnt werden – hingegen sind konzentriertere Ansätze möglich."

roughly translated:
"The solutions must not be diluted beyond the specified amounts – however, more concentrated solutions are possible."


the SDS lists:
sodium metabisulphite 10-<25%
sodium octane-1-sulphonate monohydrate 1-5%
Ammonium thiosulphate 50-90%
sodium thiosulphate waterfree 5-10%

note that plain Sodium thiosulfate is usually sold as pentahydrate, which will reduce capacity by 40% compared to Ammonium thiosulphate.


make of that what you will, I know that I wouldn't trust a solution of 34g/liter to fix films fully archival, specially not T-Max.

 

[lamerko]

Maybe the calculations are a bit off, but if in 1 liter of replenisher solution we have 200 ml of ammonium thiosulfate (58%), then for one film 33 ml are needed for replenishment, or about 7 ml of ammonium thiosulfate (58%). I assume the values are approximate for the crystalline form of sodium thiosulfate as well, but it works significantly more slowly without accelerators. In this respect, 34 g/L for single-use may be sufficient, BUT with verified fixing time and without economizing on washing.

 

[Raghu Kuvempunagar]

As per this Superfix instructions document by Tetenal, one tablet can be dissolved in 150 ml of water and used to fix film. There is no ambiguity about the minimum volume to be used at this concentration - it is 150 ml.

Weight of each tablet is 20 g. Even assuming all of this weight is due to Ammonium Thiosulphate, there can't be more than 20 g of it in one tablet.

Coming to capacity of the tablet fixer, this is what the document says about classic films:

The capacity of the fixer when used with T-grain emulsions is this:

So, 20g or less of Ammonium Thiosulphate is used in Tetenal Superfix to fix three rolls of classic 35mm film or two rolls of T-grain film.

 

[dokko]

Maybe the calculations are a bit off, but if in 1 liter of replenisher solution we have 200 ml of ammonium thiosulfate (58%), then for one film 33 ml are needed for replenishment, or about 7 ml of ammonium thiosulfate (58%). I assume the values are approximate for the crystalline form of sodium thiosulfate as well, but it works significantly more slowly without accelerators. In this respect, 34 g/L for single-use may be sufficient, BUT with verified fixing time and without economizing on washing.

it's not the total amount that is the problem, but the concentration.

ie, you can use 1 Tab of Tetenal Superfix in 150ml of water (about 1:10 concentration) and it will work with 2 films, but you certainly can't use 1 Tab in 15liters of water (1:1000 concentration) no matter how long you fix, despite the total amount of thiosulfate being the same.

obviously this is an extreme example, but at some point it will fail, and without prper validation it's much better to stay on the safe side.

 

[Raghu Kuvempunagar]

@gealto2: what is the capacity of 1 l of your fixer?

 

[Alan Townsend]

@gealto2: what is the capacity of 1 l of your fixer?

I haven't tested for that but could after mixing residual silver test solutions. I don't mess with sodium sulfide in my darkroom area, but confine it to my garage. It's been too cold and windy for that, so I'm not in the mood.

I have been using 360 ml per 30 exposure 35mm film, and calculated that is about half the average of the capacities I found online for plain fixer. That about 84 square inches of film. So 1 liter would be used for about 3 rolls. Plain fixer is good for about 30 rolls, and uses 250g/L, so my fixer is about 34/250=0.136 of normal plain fix, so should have a capacity of 4 rolls based on that.

So I would estimate my fixer capacity, based on the conservative estimate of plain fixer formulas, to be about 4 rolls. This is only a crude estimate. Likely various rounding errors in my calculations.

 

[pentaxuser]

Have to say I've never heard of diluting fixer.

Wasn't there someone on APUG or was it Photrio who used to do this in relation to print fixing. He used his dilution only once and then dumped it. That person may have been from Willamette Valley in Oregon I seem to recall?. He was certainly a relatively frequent respondent back in the day.

pentaxuser

 

[Raghu Kuvempunagar]

1 liter would be used for about 3 rolls.

Thanks.

I know you're not seeking any advice/suggestions, but have you considered dissolving your chosen amount of Thiosulphate in lesser volume of water, say ~300 ml and use it like what Tetenal recommends for its Superfix tablets? That way the concentration of Thiosulphate in your fixer would be at approximately at the same level as Superfix and capacity would remain the same. Is there a reason not do this?

 

[frost242]

Just my 2 cents. I use Bergger Neutral fixer for film and paper. For film, beside the usual 1+4 for 3 minutes, there's also a recommandation for one-shot users : 1+9 for 5 minutes.
I do it often..

 

[Alan Townsend]

Thanks.

I know you're not seeking any advice/suggestions, but have you considered dissolving your chosen amount of Thiosulphate in lesser volume of water, say ~300 ml and use it like what Tetenal recommends for its Superfix tablets? That way the concentration of Thiosulphate in your fixer would be at approximately at the same level as Superfix and capacity would remain the same. Is there a reason not do this?

Raghu, I expect both advice/suggestions, but am very stubborn. It would be very difficult to work with three times more concentrated hypo in smaller volumes. Most of my processing is ad hoc. I have sporadic sessions where I do fair amounts of film processing, mostly ortho litho films cut 4x5 tp 11x14. I do darkroom mostly in the winter, and film shooting mostly in the not winter.

One shot developers and fixers liberate me to do whatever I want whenever I want without having to manage anything and have consistent results. I am planning to start doing residual silver testing just for fun soon. By the way, I've been using 20 minute fixing times for all camera films for the last ten years or so. I'm not in a rush for fast fixing. Just recently, since I started using Gainers original MC developer, which develops very quickly, I've cut fixing times back to 10 minutes for standard films for only a single film, which I will soon test for residual silver.

I think it's poor practice to hold camera film processing in a cue until a certain number of films need processing. This isolates the camera work from personal revue for too long a time. It's best to process a roll at a time, as soon as possible, to gain perspecive on the photography aspect, which is the most important. I appreciate the suggestions.

 

[Rudeofus]

I am really surprised to read, that you fixer working solution has such poor shelf life. Typical rapid fixer lasts for weeks, and its neutral/alkaline cousin has near infinite shelf life. Therefore a proper fixer is a lot less hassle than you make it seem. Even your plain hypo solution should last indefinitely if you add 10 g/l Sodium Sulfite to it.