Light Unit Conversion Calculator
Conversion Result
Use the converter above to calculate different values and units
Light Conversion FAQs
Find answers to common questions about light measurements and photometric conversions.
The main light measurement units are: 1) Lumen (lm) - total light output, 2) Candela (cd) - light intensity in a direction, 3) Lux (lx) - illuminance or light falling on a surface, 4) Foot-candle (fc) - imperial unit of illuminance, 5) Nit (cd/m²) - luminance or screen brightness, 6) Watt (W) - radiometric power.
For LED lighting conversions: 1) Typical LED efficacy is 80-100 lumens per watt, 2) 800 lumens ≈ 8-10W LED ≈ 60W incandescent, 3) 1600 lumens ≈ 16-20W LED ≈ 100W incandescent, 4) For rough estimates, divide incandescent watts by 6 to get LED watts, 5) Always check manufacturer specifications as efficiency varies.
Lux and foot-candles are related by: 1) 1 foot-candle = 10.764 lux, 2) 1 lux = 0.0929 foot-candles, 3) Common levels: office lighting 300-500 lux (30-50 fc), 4) Sunlight 100,000+ lux (10,000+ fc), 5) For quick estimates, divide lux by 10 to get foot-candles.
Light is measured using: 1) Light meters (lux/foot-candle measurements), 2) Luminance meters (cd/m² for displays), 3) Integrating spheres (total lumens), 4) Spectroradiometers (wavelength distribution), 5) Goniophotometers (directional intensity), 6) Color meters (color temperature and rendering).
Recommended light levels are: 1) Office work: 300-500 lux, 2) Detailed assembly: 500-1000 lux, 3) Corridors: 100-150 lux, 4) Home living areas: 150-300 lux, 5) Sports facilities: 300-750 lux, 6) Operating theaters: 10,000+ lux, 7) Emergency lighting: minimum 1 lux.
Calculate light coverage using: 1) Area = lux × square meters, 2) Required lumens = desired lux × area, 3) Fixture spacing = mounting height × spacing criterion, 4) Number of fixtures = total lumens needed ÷ lumens per fixture, 5) Account for light loss factors and uniformity requirements.
Light measurement accuracy depends on: 1) Sensor calibration and quality, 2) Ambient light interference, 3) Distance and angle to light source, 4) Temperature effects on sensors, 5) Spectral response matching, 6) Cosine correction for angular measurements, 7) Regular maintenance and recalibration.
Color temperature conversions include: 1) Kelvin (K) is the standard unit, 2) Warm white: 2700-3000K, 3) Cool white: 4000-5000K, 4) Daylight: 5000-6500K, 5) Convert mired to Kelvin: 1,000,000 ÷ mired value, 6) Convert Kelvin to mired: 1,000,000 ÷ Kelvin value.