Fixer does not last forever: counting rolls
Developer announces its own death: the negatives come out thin. Fixer does nothing of the kind. A tired bath still clears the film to the eye and leaves behind silver compounds that stain and fade over years, long after anyone remembers which bottle was to blame.
The clip test
Keep the leader that is cut off before loading the reel. In room light, put a drop of fixer on the emulsion side, wait thirty seconds, then drop the whole piece into a small glass of the same fixer and start a watch. The moment the drop's spot can no longer be told from the rest is the clearing time.
- Fix for twice the clearing time, three times for tabular-grain films.
- Write the clearing time of the fresh bath on the bottle.
- When it has doubled, the bath is finished, however many rolls that took.
Counting anyway
A litre of rapid fixer at 1+4 is rated by its makers for roughly two dozen rolls of 35 mm. Tick them off on a strip of tape on the bottle. The count and the clip test should agree; when they do not, believe the clip test, because the count knows nothing of how much developer was carried over or how long the bottle stood half empty.
| Film area | Counts as |
|---|---|
| 35 mm, 36 exposures | 1 roll |
| 120 | 1 roll |
| 35 mm, 24 exposures | ⅔ roll |
| 4×5 sheet | ¼ roll |
Washing with little water
Running water for twenty minutes is not needed with a non-hardening rapid fixer. Fill the tank with water at the working temperature and invert it five times; empty it, refill, invert ten times; empty, refill, invert twenty times. Three tanks of water, and the film is washed to an archival standard. In a house on a meter, or one with a small cistern, that matters.
A last bath in distilled water with a single drop of wetting agent keeps the drying marks away where the tap water is hard. More than a drop leaves streaks of its own.
What to do with the old bath
Used fixer carries dissolved silver and should not go down the drain. Collect it in a canister; a twist of steel wool left in it for a week plates most of the silver out as a black sludge, and many municipal recycling yards take the rest with photographic or household chemicals.