Convert Skots to Foot-lamberts

Convert Skots (sk) to Foot-lamberts (fL) instantly and accurately.

Conversion Formula

fL = sk × 9.290304000e-5

About Skots

The skot (sk) equals 10⁻³/π cd/m² ≈ 3.183×10⁻⁴ cd/m², defined as one-thousandth of an apostilb. A legacy photometric unit from early German-language vision science. The dark-adapted human eye threshold is around 3×10⁻⁴ cd/m², close to 1 sk. Now obsolete; replaced by cd/m² in SI photometry. 1 sk = 10⁻³/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.

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