Olympus Om System 1-13 Matt Microprism/Split Image Focus Screen * OM-1 OM-2 OM-3

The Olympus Focusing Screen 1-13 is a standard screen for Olympus OM cameras that combines a matte area with a central microprism and split-image rangefinder for easier and more precise manual focusing. It is designed for normal photography, but when using lenses with a maximum aperture of f/5.6 or slower, the prism will darken and focusing should be done on the matte surface instead.