How to Print B&W Photographs in a Darkroom

Step 9 Test Strips

Test strips are used to determine how long to expose your photo for. They are simply strips of your photographic paper that you expose for different amounts of time. Take one sheet of paper, and cut into ~1in strips. To use the test strip:

• Set your f-stop to the smallest aperture (you'll get the best quality this way)
• Lay one strip diagonally across the easel.
• Set your timer to 30 seconds
• Using a piece of something opaque, expose about a quarter cm every 5 seconds. - You will have bars on the paper when you develop it, one exposed for 5 seconds, one for 10, one for 15, etc. all the way up to 30.
• Process the test strip as usual through fixer (more on this later)
• Wash it off
• Take it out into the light and find which bar looks the best. If the best would be a mix between 5 and 10, go for 7 or 8.
• The time that you pick will be how long you expose the entire photo for.

If all the bars are too dark, make another test strip that goes from 1 second to 5 seconds in increments of 1. If they're all too light, make a test strip that goes from 60 to 30 in increments of 5.