EV Calculator — Exposure Value from Camera Settings
Calculate Exposure Value from your aperture and shutter speed, with ISO adjustment and lux approximation.
Lens aperture (f-stop number)
Shutter speed / exposure time
Camera ISO sensitivity setting
How We Calculate This
The Exposure Value formula at ISO 100 is:
EV = log&sub2;(N² / t)
Where N is the f-number and t is the exposure time in seconds.
To adjust for ISO: EV_s = EV_100 + log&sub2;(S / 100) where S is the ISO value.
The lux approximation uses the incident light relationship: Lux ≈ 2.5 × 2^EV
Frequently Asked Questions
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Last updated: February 2026
All calculations are estimates based on standard optical and photographic formulas. Results may vary with specific equipment.