U.S. Customary System (USCS, formerly English) unit of luminance

[3.5.4] Candela per square foot (cd/ft2). Also, lumen per steradian-square foot [lm/(sr•ft2)].

Other units include the candela per square inch (cd/in2) and the lumen per steradian-square inch [lm/(sr•in2)]. (See footlambert.)

Note: These units have all been deprecated. The SI units for luminance are candelas per square meter (cd/m2), sometimes called nits.

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