LightCalc

LightCalc is a lighting calculator built specifically for cinematographers and gaffers who want to make lighting decisions faster and with confidence. Instead of relying on mental math, lookup tables and guesswork, LightCalc calculates the illuminance you need from your camera settings — then helps you work backwards to find the right fixture, modifier, distance and dimming level. With LightCalc you can: - Calculate required light levels from T-stop, ISO and shutter angle - Measure ambient light directly with your iPhone and use it in your calculations - Compare up to four fixtures side by side to quickly find the right light for the job - Solve for distance, dimming or fixture output when working with modifiers and diffusion - Browse a curated library of real-world fixtures, modifiers and diffusion - Save complete lighting setups as projects so you can revisit and adjust them later The result: less time doing calculations on set and more confidence that the light you’re putting up will actually give you the exposure and ratios you’re after. LightCalc is designed around how cinematographers actually work — turning photometric data and camera settings into practical lighting decisions you can use on set.