Luminance converter

Luminance is the brightness of a surface as seen by the eye, in candelas per square metre, which the display industry calls nits. A typical monitor or TV manages 250–400 nits, HDR content is mastered for 1,000 nits and up, and the latest phone screens reach 2,000 nits in sunlight. A cinema screen is set to 48 cd/m², 14 foot-lamberts in the projectionists' unit; a clear daytime sky is around 8,000 cd/m² and the Sun's disc 1.6 billion. The stilb, lambert and apostilb are CGS units no longer in use.