Black & white film developing manual test

If no official time is provided by the manufacturer, and our black & white film developing time calculator doesn't have the necessary information, you can perform a development test.

How to test

• Cut a test strip of film and immerse it in the developer.
• Time how long it takes to turn completely dark.
• Divide this time by three to estimate the full development time.

Example:

If a film strip darkens in 17.02 seconds, divide by 3 is 5.67 which means 5 minutes 40 seconds is the estimated development time.

This process was first published by Lomography, & Parrino, E. (2021, December 22). How to find your developing time for any black & white film. Lomography. https://www.lomography.com/magazine/347678-how-to-find-your-developing-time-for-any-black-and-white-film