Old/exhausted chemistry

JeffNunn · Nov 25, 2024

Hi to all, I’ve read through a few threads searching for an answer to this so hope I’m not asking an annoying/repeated question.

I’m trying to find out if I should expect prints to go bad over time or at some later date if I use old chemistry or semi exhausted chemistry. Meaning, if the print looks good, and looks to be properly fixed, is there a potential for it to go bad at some later point?

I’m printing on Kentmere and Ilford RC papers, and used some Ilford Multigrade paper developer that is a couple of years old and has gone brown but as far as I can tell it still works ok. For the time being at least…

I fixed with Bellini eco fix that I processed maybe 10 rolls of 35mm film through and after checking that it will clear a clip of film went ahead and fixed some prints.

I rinsed the print for two minutes under a tap but then re read the instructions a day later which recommended four mins. I thought it too late to rinse again. I didn’t use hypo clear/wash aid.

I’m not trying to be a total cheapskate and could mix up new fixer and paper developer and rinse for longer and so on but I’m just wondering about the longer term archival quality of a print that is done with semi dodgy chemicals or that is improperly rinsed. I see no obvious image degradation a week or a month later for example.

I’ve read that many will use fresh chemistry every time - if it was my job or I had a smashing photo I’d do that too and wouldn’t use old paint or caulk for a decorating job as a comparison.

I realise I’m trying to see if I’ll regret these shortcuts later!

As a separate question, Is all of this more important with FB papers?

Melvin J Bramley · Nov 25, 2024

JeffNunn said:
Hi to all, I’ve read through a few threads searching for an answer to this so hope I’m not asking an annoying/repeated question.

I’m trying to find out if I should expect prints to go bad over time or at some later date if I use old chemistry or semi exhausted chemistry. Meaning, if the print looks good, and looks to be properly fixed, is there a potential for it to go bad at some later point?

I’m printing on Kentmere and Ilford RC papers, and used some Ilford Multigrade paper developer that is a couple of years old and has gone brown but as far as I can tell it still works ok. For the time being at least…

I fixed with Bellini eco fix that I processed maybe 10 rolls of 35mm film through and after checking that it will clear a clip of film went ahead and fixed some prints.

I rinsed the print for two minutes under a tap but then re read the instructions a day later which recommended four mins. I thought it too late to rinse again. I didn’t use hypo clear/wash aid.

I’m not trying to be a total cheapskate and could mix up new fixer and paper developer and rinse for longer and so on but I’m just wondering about the longer term archival quality of a print that is done with semi dodgy chemicals or that is improperly rinsed. I see no obvious image degradation a week or a month later for example.

I’ve read that many will use fresh chemistry every time - if it was my job or I had a smashing photo I’d do that too and wouldn’t use old paint or caulk for a decorating job as a comparison.

I realise I’m trying to see if I’ll regret these shortcuts later!

As a separate question, Is all of this more important with FB papers?

If it printed to a standard you accept then all is well.
Your wash times are short but as long as the film clip cleared within a minute , re wash.
As long as you are not wishing to turn out limited edition prints then there is much money to be saved using old stock chemistry and more so with old stock paper and film, depending upon the manufacturer that is!

Don_ih · Nov 25, 2024

JeffNunn said:
I rinsed the print for two minutes under a tap but then re read the instructions a day later which recommended four mins.

Two minutes rinse for one rc print is likely fine.

Nothing will happen due to using old developer other than possible muddy prints with a somewhat brown tone.

Using fixer that is worn out will result in eventual printing out of the unfixed residual silver - it'll show up purple or sometimes brown on a print, generally in the whitest parts. If that happens, refixing won't clear it.

The main drawback to using worn out chemicals is you end up with improper results. Exposing your paper in a certain way should generate a certain print. Spent developer won't reliably do that. And underfixing the print just turns it into garbage.

Melvin J Bramley · Nov 25, 2024

Don_ih said:
Two minutes rinse for one rc print is likely fine.

Nothing will happen due to using old developer other than possible muddy prints with a somewhat brown tone.

Using fixer that is worn out will result in eventual printing out of the unfixed residual silver - it'll show up purple or sometimes brown on a print, generally in the whitest parts. If that happens, refixing won't clear it.

The main drawback to using worn out chemicals is you end up with improper results. Exposing your paper in a certain way should generate a certain print. Spent developer won't reliably do that. And underfixing the print just turns it into garbage.

Fixer is easily tested.
The original poster did that correctly!

Don_ih · Nov 25, 2024

Melvin J Bramley said:
Fixer is easily tested.
The original poster did that correctly!

Spent fixer will clear undeveloped film. It'll typically clear the shadows of developed film and leave silver in the midtones. Fixing developed silver seems more difficult than undeveloped. Good fixer should clear undeveloped film in less than half the time needed to clear developed film.

MattKing · Nov 25, 2024

I would get some fresh fixer and re-fix the prints.
And it isn't a good idea to re-use fixer that has been used with film to fix prints - even if that fixer will clear film.
There are all sorts of byproducts that may remain in partially spent fixer, and the effects of those byproducts are different, depending on whether the fixer has been used for film or for paper.
As for the developer, if it is giving you the density and contrast you want, and you don't see signs of staining, it will be usable. Just don't count on it behaving identically to fresh developer.

xkaes · Nov 25, 2024

As mentioned it's easy to test fixer. If you are worried about prints you already fixed, fix them again -- also as suggested. And if you are really worried about longevity, finish your prints with some sort of stabilizer -- selenium toner, Sistan, etc.

JeffNunn · Nov 26, 2024

As I drifted off to sleep yesterday I had visions of a round table of APUG/Photrio photographers shaking their heads and tutting, so thanks to all for the polite and informative answers.

Melvin J Bramley said:
If it printed to a standard you accept then all is well.
Your wash times are short but as long as the film clip cleared within a minute , re wash.
As long as you are not wishing to turn out limited edition prints then there is much money to be saved using old stock chemistry and more so with old stock paper and film, depending upon the manufacturer that is!

I suppose the key point is - if it’s an acceptable standard to me then all good, I shouldn’t expect some latent failure.

Don_ih said:
Two minutes rinse for one rc print is likely fine.

Nothing will happen due to using old developer other than possible muddy prints with a somewhat brown tone.

Using fixer that is worn out will result in eventual printing out of the unfixed residual silver - it'll show up purple or sometimes brown on a print, generally in the whitest parts. If that happens, refixing won't clear it.

The main drawback to using worn out chemicals is you end up with improper results. Exposing your paper in a certain way should generate a certain print. Spent developer won't reliably do that. And underfixing the print just turns it into garbage.

As a test I left one print unfixed and have observed the printing out of the purple and brown unfixed silver, and yes that went in the bin.

The intention is to get better at printing and achieve a decent quality and standard, so I appreciate the point of reliable and reproducible results. That’s the same reason I personally stopped using caffenol and stopped doing stand developing - unpredictable results, although I know I could apply stricter controls to both techniques there too

Don_ih said:
Spent fixer will clear undeveloped film. It'll typically clear the shadows of developed film and leave silver in the midtones. Fixing developed silver seems more difficult than undeveloped. Good fixer should clear undeveloped film in less than half the time needed to clear developed film.

I’m glad you compared it to fixing film as that would have been another question. I have under-fixed film and know how that looks, but good to have a guideline.

I should add the film clip cleared in seconds, but I hadn’t considered the point MattKing made that the fixer can be contaminated - that would explain little spots and other artefacts.

MattKing said:
I would get some fresh fixer and re-fix the prints.
And it isn't a good idea to re-use fixer that has been used with film to fix prints - even if that fixer will clear film.
There are all sorts of byproducts that may remain in partially spent fixer, and the effects of those byproducts are different, depending on whether the fixer has been used for film or for paper.
As for the developer, if it is giving you the density and contrast you want, and you don't see signs of staining, it will be usable. Just don't count on it behaving identically to fresh developer.

In terms of density, is there a rule of thumb to measure this or is it strictly a densitometer task? I see deep blacks and clean whites and all sorts of greys, but maybe I’ve not understood what print density is.

Thanks again to all!

koraks · Nov 26, 2024

JeffNunn said:
I’m glad you compared it to fixing film as that would have been another question. I have under-fixed film and know how that looks, but good to have a guideline.

Comparing film fixing to print fixing, from a practical viewpoint, the main problem is that it's fairly easy to see if your film is fixed, but it's not possible to tell by eye if paper is fixed thoroughly. The only reliable way that I know of is through chemical means. The easiest is to drop some developer on a border of the print and see if any density develops (you can only tell after the developer has been washed off again). If a stain is visible, the print can be re-fixed. The stain may be removed with Farmer's reducer. What this test will not show (reliably) is whether any silver halide remains in other areas beside the exact spot you tested. So it's a bit of a half-a&&ed test to begin with, and really, it should be precluded by using a proper regime where you use fixer dedicated to fixing prints*, keep track of the surface area of paper you've fixed with it and compare this against the stated capacity by the manufacturer of the fixer, while erring to the conservative side in doing so.

* As to using fixer for prints that has been previously used to fix film: it's best to avoid this. Film tends to have a different chemical makeup and in particular contains iodide, which slows down fixing. It's best to use film fixer for film and paper fixer for prints. It can be the same product, but keep the working strength batches separated.

JeffNunn said:
In terms of density, is there a rule of thumb to measure this or is it strictly a densitometer task? I see deep blacks and clean whites and all sorts of greys, but maybe I’ve not understood what print density is.

Density is difficult to judge visually unless you use a known-good reference. Such a reference can be easily made by taking a strip of the paper you use, take it into room light and develop it in fresh print developer for a time that's guaranteed to develop out the paper entirely. You can watch progress as it develops; you'll note that after a while, it doesn't change anymore. Then fix and wash this strip as you normally do with prints and keep it at hand as your maximum density reference for this paper/developer combination.
You can make a white reference in a similar way, by taking a strip of paper, skipping over the development and instead fixing it out and then washing it. Especially if you're using paper that has been sitting around for some time, or paper of unknown providence, you could in addition take a strip of paper that has not been exposed to any light at all, develop it as you normally do with prints, then fix and wash. Compare this strip to the strip that went straight into the fixer. This will tell you how much (if any) fogging density is present on the paper.

JeffNunn · Nov 26, 2024

koraks said:
Comparing film fixing to print fixing, from a practical viewpoint, the main problem is that it's fairly easy to see if your film is fixed, but it's not possible to tell by eye if paper is fixed thoroughly. The only reliable way that I know of is through chemical means. The easiest is to drop some developer on a border of the print and see if any density develops (you can only tell after the developer has been washed off again). If a stain is visible, the print can be re-fixed. The stain may be removed with Farmer's reducer. What this test will not show (reliably) is whether any silver halide remains in other areas beside the exact spot you tested. So it's a bit of a half-a&&ed test to begin with, and really, it should be precluded by using a proper regime where you use fixer dedicated to fixing prints*, keep track of the surface area of paper you've fixed with it and compare this against the stated capacity by the manufacturer of the fixer, while erring to the conservative side in doing so.

* As to using fixer for prints that has been previously used to fix film: it's best to avoid this. Film tends to have a different chemical makeup and in particular contains iodide, which slows down fixing. It's best to use film fixer for film and paper fixer for prints. It can be the same product, but keep the working strength batches separated.

Density is difficult to judge visually unless you use a known-good reference. Such a reference can be easily made by taking a strip of the paper you use, take it into room light and develop it in fresh print developer for a time that's guaranteed to develop out the paper entirely. You can watch progress as it develops; you'll note that after a while, it doesn't change anymore. Then fix and wash this strip as you normally do with prints and keep it at hand as your maximum density reference for this paper/developer combination.
You can make a white reference in a similar way, by taking a strip of paper, skipping over the development and instead fixing it out and then washing it. Especially if you're using paper that has been sitting around for some time, or paper of unknown providence, you could in addition take a strip of paper that has not been exposed to any light at all, develop it as you normally do with prints, then fix and wash. Compare this strip to the strip that went straight into the fixer. This will tell you how much (if any) fogging density is present on the paper.

This is all fantastic advice also, I will make those reference sheets as you say. I have new chemicals and paper but was just surprised to see how far I was taking the set I had already made up

I dumped all chemicals the other day so will make up a film fixer and paper fixer bottle, that’s great.

Seems I was pushing my luck a bit here!

pentaxuser · Nov 26, 2024

JeffNunn said:
Seems I was pushing my luck a bit here!

Except that I don't think you were in respect of a 2 min wash with RC paper under running water

pentaxuser

Saganich · Nov 26, 2024

It's a good question I used to spend 8-10 hrs in the darkroom for a print, now those hours have to be parsed out over days and weeks in sessions no longer than 3 hrs. When making final prints I always use fresh developer (I use a high concentration stock developer). Fix is just tracked by surface area and replaced as needed as I do with film. Used developer is used for initial work prints, which may take a few days. I'll spend 3 hrs on work prints for 2 or 3 images, then evaluate next day, wonder what the hell I was thinking, make lots of adjustments, make more work prints, repeat, until I'm happy and think I can bang out 10 final prints. Then I'll mix up fresh developer and make final prints, which get proper washing, selenium, and some will be toned. Then the ones that survive my spot toning get matted. Work prints are shredded. Fiber paper gets second fix, a long soak, and residual hypo check.

Doremus Scudder · Nov 26, 2024

Read the tech sheets
Follow the directions
EZPZ

JeffNunn · Nov 26, 2024

pentaxuser said:
Except that I don't think you were in respect of a 2 min wash with RC paper under running water

pentaxuser

Appreciate you saying so. Also the place I bought the fix from says:

“Composed of Ammonium Iposolfite it is formulated specifically for black and white films and papers…for the environmentally conscious this is about the cleanest fixer you can get.

The nice thing about this fix is that it is easily eliminated thus has reduced washing times and is more eco friendly than some other fixers.”

Saganich said:
It's a good question I used to spend 8-10 hrs in the darkroom for a print, now those hours have to be parsed out over days and weeks in sessions no longer than 3 hrs. When making final prints I always use fresh developer (I use a high concentration stock developer). Fix is just tracked by surface area and replaced as needed as I do with film. Used developer is used for initial work prints, which may take a few days. I'll spend 3 hrs on work prints for 2 or 3 images, then evaluate next day, wonder what the hell I was thinking, make lots of adjustments, make more work prints, repeat, until I'm happy and think I can bang out 10 final prints. Then I'll mix up fresh developer and make final prints, which get proper washing, selenium, and some will be toned. Then the ones that survive my spot toning get matted. Work prints are shredded. Fiber paper gets second fix, a long soak, and residual hypo check.

That’s an interesting idea actually, that would give me a use for old stuff.

I’m going to look up selenium toning and whatnot, thanks for the rundown on your workflow also.

Doremus Scudder said:
Read the tech sheets
Follow the directions
EZPZ

I guess that sums it up mate ezpz indeed!

koraks · Nov 27, 2024

JeffNunn said:
Also the place I bought the fix from says:

“Composed of Ammonium Iposolfite it is formulated specifically for black and white films and papers…for the environmentally conscious this is about the cleanest fixer you can get.

The nice thing about this fix is that it is easily eliminated thus has reduced washing times and is more eco friendly than some other fixers.”

This is, with all due respect, marketing/sales bogus. The proper name is not "Ammonium Iposolfite", but ammonium thiosulfate, and it's the basis of ALL modern rapid fixers (which represents probably around 95% of the sales volume), color and B&W. The reduced wash time remark refers most likely to the comparison with sodium thiosulfate fixer, which can still be bought and is sometimes mixed from raw material (pool dechlorination is often done with sodium thiosulfate, making it a cheap source), but the vast majority of people use a rapid fixer. Mind you, the whole wash argument is really only relevant to fiber based prints anyway; with film and RC paper, it's not even much of an issue since they don't require much washing to begin with.

What this shows mostly is that it's difficult to create a competitive advantage with a generic commodity such as fixer. It's a bit like "buy our mud, because our mud is muddier than Jack's mud, which isn't quite as muddy."

Sorry for the 'bah, humbug'.

JeffNunn said:
I’m going to look up selenium toning

Selenium toning is quite nice. But if we're talking 'eco-friendly' - selenium toner is the exact opposite. You can reu-se and replenish it (ask @Doremus Scudder) and a little goes a long way, but still. If you mention stuff like dichromate etc. people tumble all over each other to point out how HORRIBLE it is, and yet, without batting an eye, they'll mix a tray of selenium toner for an 'archival' treatment of their prints (don't get me started on that one).

JeffNunn · Nov 27, 2024

koraks said:
our mud is muddier than Jack's mud, which isn't quite as muddy.

Wow, glad I quoted that, obviously a marketing trick aimed at people like me! Ah well now I know. Bellini chemistry isn’t expensive and seems as good as any other and that fixer just came in a kit with the developer I wanted.

koraks said:
'eco-friendly'

Wasn’t exactly the goal but I guess every little helps. I suppose it is something to think about.

Thanks for taking the time to set that straight for me

xkaes said:
Sistan

Reading the data sheets for this as well…

Fatih Ayoglu · Nov 28, 2024

You can test the fixer with a strip of paper as well. What I usually do is; cut a 7cmx1cm strip of paper. Under the red light, mark each 1cm with a marker, so I have 6 testing areas. Then I dip the paper into fixer, for a minute up to the 1st marker, then dip further more up to the second marker and wait for another minute and so on. I do this 4-5 minutes. Then give it a good wash and turn the lights on, probably under a direct sun light. The area that still shows pure white is your fixing time as underfixed are turns pinkish.

koraks · Nov 28, 2024

Fatih Ayoglu said:
Then give it a good wash and turn the lights on, probably under a direct sun light. The area that still shows pure white is your fixing time as underfixed are turns pinkish.

Good idea; you could also put it into the developer tray at this point. Any remaining silver halide will develop out, causing clearly visible grey to brown/purple fog.

Fatih Ayoglu · Nov 28, 2024

koraks said:
Good idea; you could also put it into the developer tray at this point. Any remaining silver halide will develop out, causing clearly visible grey to brown/purple fog.

If I am not wrong, the original method involves indeed to put in the developer but I am concerned of ruining it despite a good wash. One could say that you can use like 10ml mixed developer solution if you have some sort of tube

koraks · Nov 28, 2024

You could drop some developer onto the strip if you're concerned ruining it. I'm not too concerned about this, especially with a smallish strip of RC paper. There'll never be enough fixer remaining on it (after a rinse) to noticeably affect the developer.

Marcelo Paniagua · Nov 28, 2024

As posted before, probably the more critical are for long term/stable prints is the fix. Usually, my savings are on the developer area. If developer meets the criteria I want, then it is suitable.

I use fresh chemistry most of time because I make it myself (rodinal, POTA, E76 and other sorts of Phenidone/Citric acid developers). Since fixer problems may not be evident immediately, I usually try to keep fresh fixed.

Probably what I mean, be a cheapskate on developer, dont cut corner on fixer.

Regards

Doremus Scudder · Nov 29, 2024

JeffNunn said:
Appreciate you saying so. Also the place I bought the fix from says:

“Composed of Ammonium Iposolfite it is formulated specifically for black and white films and papers…for the environmentally conscious this is about the cleanest fixer you can get.

The nice thing about this fix is that it is easily eliminated thus has reduced washing times and is more eco friendly than some other fixers.”

Jeff,
Don't jump to conclusions (and Koraks too) about Bellini fixers. This isn't marketing hype, just a bit of "lost in translation." The Italian term for ammonium thiosulfate is, indeed, "ammonium iposulfite," (French is " iposulfite d'ammonium," the "iposulfite" is related to "hyposulfite," the older English term for "thiosulfate"). The claim of reduced washing time likely has to do with the fact that the fixer is neutral or alkaline; neutral or alkaline fixers do indeed wash out more quickly. More eco friendly is also likely due to the fact that there are no acids or hardeners in the fixer. I'm sure Bellini fixer is a fine rapid fixer on a par with many others.

If you can't decipher the instructions for the Bellini fixer due to confusing translations, you can use the instructions for another similar product (Ilford's tech sheet for Rapid Fixer is quite comprehensive, or maybe TF-5 has a good tech sheet as well).

There are standard and well-recognized tests for both residual silver (adequate fixing) and residual hypo (adequate washing. The former include the Kodak ST-1 and Selenium Toner tests, the latter is the HT-2 test. A quick search here and over on the LF forum should turn up everything you need to know about those.

Hope this helps,

Doremus

koraks · Nov 30, 2024

Doremus Scudder said:
Don't jump to conclusions (and Koraks too) about Bellini fixers.

I don't - fact is that in an English translation, they use an Italian compound name, which is unnecessarily confusing and technically incorrect.
That their fixer (FX100) is a near-neutral fixer is indeed correct.

It's a perfectly fine fixer and very comparable to color film fixer.

Doremus Scudder said:
More eco friendly is also likely due to the fact that there are no acids or hardeners in the fixer.

Their FX5 fixer is a two-part fixer apparently much like Kodak F5 (non-rapid) fixer with separate hardener (boric acid). FX100 is a rapid near-neutral fixer and contains no hardener.

Doremus Scudder said:
If you can't decipher the instructions for the Bellini fixer due to confusing translations, you can use the instructions for another similar product (Ilford's tech sheet for Rapid Fixer is quite comprehensive, or maybe TF-5 has a good tech sheet as well).

It's lamentable that Bellini choose to not publish MSDS on their website and instead force users to contact them in order to be sent the MSDS. This information really should be made accessible without having to jump through hoops.
Their labeling of a non-hardening rapid fixer as 'eco' and emphasizing its eco-friendliness to me feels the same as labeling table salt as an 'eco friendly choice'. It's technically correct, but virtually meaningless. In case someone might argue "but their near-pH neutral, non-hardening fixer requires less wash water to be used" - yes, in theory. In practice, with RC paper and film, the difference isn't very meaningful. And for fiber based paper, the practical approaches towards washing all rely on a massive degree of conservatism lest the end result be 'archival', so again, it's not a very meaningful difference. The 'eco' argument looks good only on paper (pun intended).

JeffNunn · Nov 30, 2024

Fatih Ayoglu said:
You can test the fixer with a strip of paper as well. What I usually do is; cut a 7cmx1cm strip of paper. Under the red light, mark each 1cm with a marker, so I have 6 testing areas. Then I dip the paper into fixer, for a minute up to the 1st marker, then dip further more up to the second marker and wait for another minute and so on. I do this 4-5 minutes. Then give it a good wash and turn the lights on, probably under a direct sun light. The area that still shows pure white is your fixing time as underfixed are turns pinkish.

This is great advice, I understand how I’d go about preparing this.

koraks said:
Good idea; you could also put it into the developer tray at this point. Any remaining silver halide will develop out, causing clearly visible grey to brown/purple fog.

I will have to try this also to see how that works. I get the idea!

JeffNunn · Nov 30, 2024

Doremus Scudder said:
Jeff,
Don't jump to conclusions (and Koraks too) about Bellini fixers. This isn't marketing hype, just a bit of "lost in translation." The Italian term for ammonium thiosulfate is, indeed, "ammonium iposulfite," (French is " iposulfite d'ammonium," the "iposulfite" is related to "hyposulfite," the older English term for "thiosulfate"). The claim of reduced washing time likely has to do with the fact that the fixer is neutral or alkaline; neutral or alkaline fixers do indeed wash out more quickly. More eco friendly is also likely due to the fact that there are no acids or hardeners in the fixer. I'm sure Bellini fixer is a fine rapid fixer on a par with many others.

If you can't decipher the instructions for the Bellini fixer due to confusing translations, you can use the instructions for another similar product (Ilford's tech sheet for Rapid Fixer is quite comprehensive, or maybe TF-5 has a good tech sheet as well).

There are standard and well-recognized tests for both residual silver (adequate fixing) and residual hypo (adequate washing. The former include the Kodak ST-1 and Selenium Toner tests, the latter is the HT-2 test. A quick search here and over on the LF forum should turn up everything you need to know about those.

Hope this helps,

Doremus

Thanks Doremus, and it seems I’d be unlikely to have found the history of the word itself as you described it - interesting!

Looking across their products it seems they have a few things marketed as ‘quicker’ or ‘easier’ - which may be down to the distributor having a slight bias/wanting to support Bellini. Either way I’ve learnt here that the way to really know is look at the data sheets as you and Koraks have pointed out and then I’ll know what it’s made of and can choose properly.

Bellini also have a selenium toner, I almost asked the other day if someone here could point me in the direction of a place I could buy a selenium toned print just so I could see one in the flesh, but it’s not too expensive to buy and have a go with.

Good to know the fix and wash tests exist, for the moment I might be fine just following your Ezpz advice and as others have said just count up how much I’ve fixed and replace on time and I’ll generally be alright

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