Keylight Expressions

An aperture, ISO, strobe power and distance calculator

Off-axis flash photography is challenging. Optimal exposure settings require a balance of ISO sensitivity, aperture level, strobe power and distance to the subject. Strobe intensity varies between manufacturers and models, and when external light modifiers such as umbrellas, soft-boxes and lighting gels are used, quickly determining correct exposure settings can be challenging at best, and frustrating at the worst. Keylight Expressions removes the guesswork and saves you valuable time when setting up your lighting.