If you’re developing black & white film on your own, you’ve probably heard about those one-shot developers. Mix ’em, use ’em and trash ’em, because they got depleted in that one development process, right?
Usually, one-shot developers are used either very diluted from the start, like Rodinal/R09 One-Shot or are used less diluted, but also get depleted quickly, like Xtol or FX-39. Once the dilution goes through the development process, almost all of the active components are spent. Also, contact with the air starts the oxidation process, which decreases the amount of active components. Developer oxidation is not a fast process, but it will decrease the strength of the dilution over some time nonetheless.
So, what’s that “two-shot” nonsense, then?
What is it?
Obviously, that’s a one-shot developer reused!
During the process, almost no developer gets depleted completely, there’s always1 some percentage of the developer still active. Knowing that it becomes obvious what “two-shot” development is – a way of using up whatever is left of the developer in the working dilution. It’s not a risk-free, or easy process! Because there is no way of knowing the exact percentage of active developer left, there are no formulas to calculate the needed time, it is a calculated risk, pure guesswork and hope for the best. The best practice with “two-shot” development (or “multi-shot”) is to use the dilution as quickly as possible, with as short exposure to air as possible.
I have used Kodak Xtol and Adox XT-3 1+1 dilution up to six times, all developed in under 24 hours. Xtol gets hazy when it oxidizes and some compensation time is advised, but the best idea would be to stop using it once the haziness becomes apparent. I’ve started compensating for the exhaustion after the third roll – +10% to development time for the fourth, +20% for the fifth, and +30% for the last, sixth roll.
I reused Adox FX-39 II with only two rolls, one in 1+9 and the other in 1+19 dilution. The first time, 1+19 dilution, I added no compensation, while the other time, when reusing 1+9 dilution I added 10% to the development times for the standard 1+1 dilution. Again, the same advice is applied here – use it up as quickly as possible. FX-39 oxidizes significantly faster than XT-3, so keeping the air out of the surface should be a priority if it’s not reused immediately, and any prolonged delay should be avoided.
For keeping the developer as fresh as possible, any antioxidizing agent should work just fine. Many shops that sell darkroom chemicals also sell Tetenal Protectan Spray, but any gas heavier than air works just as fine – argon for welding and protecting wine, propane and butane from lighter cans. Glass beads and marbles to raise the level to the top of the bottle also work well, but all that glass will add significant weight and make handling bottles harder. Collapsible bottles are a staple of darkroom accessories and are a perfectly viable solution. I find them hard to clean, and plastic isn’t the best for storing chemicals for longer periods.
Data-sheet
All numbers are based on my personal experience, your results might vary, and I hold no responsibility if something goes wrong – it could, this is an experiment, so do not reuse one-shot developers for film you value highly.
| Kodak Xtol / Adox XT-3 | Adox FX-39 II | |
|---|---|---|
| How many total rolls can be developed | up to 6 | up to 2 |
| How long can it be stored | up to 24h | up to 1h |
| Compensation time for the first reuse | – | up to +10% |
| Compensation time for reuses 2-3 | – | – |
| Compensation time for reuses 3-6 | +10% for every additional reuse | – |
Using an antioxidizing agent (or other methods for expelling the air) can extend the storage time significantly.
Photo examples
AgfaPhoto APX 400, Adox FX-39 II 1+9, reused the first time;
11:00 min at 22°C.
AgfaPhoto APX 400, Adox FX-39 II 1+9, reused the first time;
11:00 min at 22°C.
AgfaPhoto APX 100, Adox FX-39 II 1+19, reused the first time;
13:00 min at 21.5°C.
AgfaPhoto APX 100, Adox FX-39 II 1+19, reused the first time;
13:00 min at 21.5°C.
AgfaPhoto APX 400, Adox XT-3 1+1, reused the fifth time;
12:15 min at 22.5°C.
AgfaPhoto APX 400, Adox XT-3 1+1, reused the fifth time;
12:15 min at 22.5°C.
Conclusion
Judging by the examples, both developers work acceptably well when reused. But reusing a developer that wasn’t designed for that is a strictly experimental procedure – it works fine until it doesn’t, there’s no guarantee, and there are no recommended development times. Even with antioxidizing agents, oxidation is the real issue in the case of FX-39 II, but not so much with Xtol and XT-3. Speed is the key, the faster you can cycle the process, the less oxidation will occur. If the developer starts to haze up and/or change the colour, it is probably time to stop using it.
I had a positive experience with both developers, diluted and reused Xtol is my go-to way of using Xtol, I’ve developed close to 30 rolls of film that way, all with the same results that I like. I will continue to experiment with FX-39 II, I still haven’t decided if the process produces results I’m happy with. At least I’m not flushing still usable developer, this way.
Once again, use this post as a guideline only, not a recommendation. You’re experimenting and you’re on your own with development times, do not use this process to develop important films. If you do, write down your observations and adjust your process accordingly, you might be on the way to discovering a process that works for you.
Good luck and have fun developing film!
- Except if the developer was used for the stand process – like Rodinal 1+100 – where all the developer gets fully depleted. ↩︎
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