What harm can do expired chemicals ?

[mavr]

I wonder if someone can let me know if expired developers for developing films (i.e., from a bottle of Rodinal or HC110 opened a year or more ago) produce much worse results than those from freshly opened bottles? What kind of problems can appear (for example, more grain) when using outdated developers, even though if they are used in correct dilution at correct temperature (correct meaning, as given for 'fresh' developer)?

 

[Ian Grant]

With both those developers you should be fine, but in general most developers don't last that long and you risk ruining films which may be important. Usually under development or even no development at all.

Do a short test first.

Ian

 

[Darkroom317]

What about powered chemicals that have not been mixed?

 

[Ian Grant]

They don't last forever, impossible to tell as every formula will be different. But some 1960's developers I've tried have been oxidising in the packets and are completely useless.

Polythene sealed chemistry goes off, the packaging breathes over time, newer foils and older Tins maybe OK, but again you'd need to test.

Ian

 

[Darkroom317]

Also, what about Technidol? it has been in a refrigerator for some reason. If not, any other good developers for Tech Pan?

 

[2F/2F]

In general, try them on a crap roll and let us know what happens.

Specifically, those two will be fine. FINE. They last forever.

 

[nworth]

HC-110 and Rodinal have terrific shelf lives, even after being opened. A year-old bottle should not be a problem, unless it has been stored very poorly. Generally, liquid chwmicals discolor as they go bad, but Rodinal may be dark to begin with. Powdered chemicals usually last a very long time in their original, sealed containers. Most will still be good after 10 years. If the material is badly caked or discolored, it is probably bad, however.

When a developer goes bad, it usually just doesn't work as intended. Negatives or prints will usually be underdeveloped or not developed at all. Stains may also appear.

 

[Darkroom317]

All of the powders I have seem loose not caked. I have Microdol-X in a packet, Microdol in a can, Perceptol in a box. and Selectol in a packet.

 

[BobCrowley]

I just checked some very very old (decades?) HC-110 against some fresh that just came in and the old HC-110 doesn't seem pettered at all, despite being stored in a hot closet. Side by side the two processed out the same, which surprises me. The only reason I did this is I am trying to learn about developer and photo chemical shelf life in general. Very interested in hearing about specific developers that clearly go bad after, say, three or four years, dry or liquid. Otherwise why take a chance - get fresh if you can.

 

[Ian Grant]

Bob, HC-110, Ilfotec LC & HC and I think Tmax dev are the real exceptions in terms of extreme shelf life due to their containing little or no water so the developing agents can't oxidise in thr concentate solution.

MQ developers have a short shelf life in solution up to a year, PQ very much longer up to 3-4 years, other developing agents often have eve shorter shelf lives once mixed. But most van be extended greatly by mixing in Glycol or similar which is the principle behind HC110, Iltotec HC etc.

Ian

 

[BobCrowley]

The glycol in 110 sure is viscous. A home-made reagent with HC-110, some dry sodium thiosulfate, a strong alkali such as sodium hydroxide, and perhaps some sodium sulfite solvent might be mixed up without adding water, or maybe only a little water. I wonder if I could produce a chemical film capable of rehydration to apply to a receiver sheet as a DTR field development material, activated by water? It would have to rehydrate fast though. It would be good if it lasted a very long time, and not need to be put in a pod.

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