Convert Foot-lamberts to Candelas per square metre

Convert Foot-lamberts (fL) to Candelas per square metre (cd/m²) instantly and accurately.

Foot-lamberts (fL)
Candelas per square metre (cd/m²)

Conversion Formula

cd/m² = fL × 3.4262591

About Foot-lamberts

The foot-lambert (fL) equals 1/(π×0.09290304) cd/m² ≈ 3.426 cd/m², the luminance of a perfect diffuse surface emitting 1 lumen per square foot. The SMPTE standard for cinema screen luminance is 14 fL (≈48 cd/m²); home projectors are rated 10-35 fL. Still standard in US cinema and theatre engineering. 1 fL = 1/(π×ft²) cd/m².

About Candelas per square metre

The candela per square metre (cd/m²), informally called the nit, is the SI coherent unit of luminance. A typical laptop screen is 250-500 cd/m²; an HDR TV reaches 1 000-4 000 cd/m²; a clear blue sky is ~3 000-8 000 cd/m². Luminance is the photometric quantity directly perceived as brightness. 1 cd/m² = 1 nit.

Quick Reference Table

Foot-lamberts (fL)Candelas per square metre (cd/m²)
1 fL3.42626 cd/m²
2 fL6.85252 cd/m²
5 fL17.1313 cd/m²
10 fL34.2626 cd/m²
25 fL85.6565 cd/m²
50 fL171.313 cd/m²
100 fL342.626 cd/m²

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