Darkroom Timer

Overview

A darkroom timer does two jobs. For film it counts down development time. For printing it controls the enlarger lamp, and that is where the precision matters: an exposure of 11.5 seconds must be reproducible to a fraction of a second, or your test strips are meaningless.

The features that separate a good timer from a bad one are all about workflow. A foot switch lets you start and stop exposure with both hands free to dodge and burn. Repeat and pause functions let you run a sequence of identical exposures. Audible ticks let you count seconds without looking.

For film development you want a countdown with a loud, unambiguous alarm. For printing you want a count-up mode as well, so you can time a dodging sequence and then subtract it from the total.

What it does well

• Reproducible exposures to a tenth of a second
• Foot switch leaves both hands free to dodge and burn
• Count-up mode for building sequences
• Audible ticks for counting without looking
• Also useful for timing film development to the second

Safety notes

Working notes

• Practise with the foot switch until you can start an exposure without looking down.
• Use count-up mode to time a dodge, then subtract it from the total exposure.
• Write down every exposure — a print is only repeatable if the number is recorded.
• Check the repeatability once a year by timing ten one-second exposures against a stopwatch.

Compatible with