Black Cat Decoder

To use this Black Cat Decoder first select a ULC letter. A listing of scenes, all requiring the same amount of light, will be displayed below the chart. Any film speed (ISO), shutter speed or f-stop may be selected to display a "good exposure" or under/over exposure. Play with these settings until you have an appropriate combination. You may also use this chart to decode a photograph and find its ULC. This will determine the amount of light that was required to take the photograph. Place the ISO, shutter speed and f-stop used to make the exposure, then select the ULC letter that shows "good exposure"

ULC ISO Shutter

This interactive chart was created by Frank Kujawski
and is based on the Black Cat Extended Range Exposure Guide by Jim Lehman








Version 3.0