luminance vs brightness

luminance and brightness both are nouns.

Word	Noun	Adjective	Verb	Adverb
luminance	Yes	No	No	No
brightness	Yes	No	No	No

As nouns, luminance and brightness are synonyms defined as:

luminance and brightness: the quality of being luminous; emitting or reflecting light

Other synonyms of luminance include brightness level, light, luminosity, luminousness.

luminance (noun)	brightness (noun)
the quality of being luminous; emitting or reflecting light	the location of a visual perception along a continuum from black to white
	the quality of being luminous; emitting or reflecting light
	intelligence as manifested in being quick and witty