Darkroom Tip: The Clip Test: Never Guess at Fixer

Snip a scrap of undeveloped film leader, drop it in your fixer, and time how long it takes to turn completely clear. Your fixing time is twice the clearing time.

Fresh rapid fixer typically clears film in well under a minute. As the fixer loads up with silver, clearing stretches out — when the clearing time reaches roughly double what it was fresh, the fixer is done. Dump it (responsibly — silver-laden fixer shouldn't go down the drain; many labs take it).

Track rolls-through-the-bottle with Analogly's Chemistry Tracker exhaustion warnings and the clip test becomes confirmation, not detective work.