Convert Lamberts to Foot-lamberts
Convert Lamberts (L) to Foot-lamberts (fL) instantly and accurately.
Conversion Formula
fL = L × 929.0304
About Lamberts
The lambert (L) equals 10⁴/π cd/m² ≈ 3 183 cd/m², the luminance of a perfect diffuse surface emitting 1 lumen per square centimetre. The CGS practical luminance unit. An incandescent lamp globe at 3 200 K has luminance ~1 L; a clear sky is ~0.94 L. Superseded by cd/m² in SI photometry. 1 L = 10⁴/π cd/m².
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.
Quick Reference Table
| Lamberts (L) | Foot-lamberts (fL) |
|---|---|
| 1 L | 929.03 fL |
| 2 L | 1858.06 fL |
| 5 L | 4645.15 fL |
| 10 L | 9290.3 fL |
| 25 L | 23225.8 fL |
| 50 L | 46451.5 fL |
| 100 L | 92903 fL |