footlambert (fL)

Footlambert (fL) is an illumination quantity emitted or reflected from diffuse surfaces.

The Footlambert is used in projection. The higher the value, the brighter the projection. The Footlambert is an obsolete illumination unit for luminous intensity that was used in the USA. 1 footlambert equals 1 candela per square foot, and that equals 3,426 candela per square meter( cd/m2) or 3,426 nits.