pitch blackness vs total darkness

pitch blackness and total darkness both are nouns.

Word	Noun	Adjective	Verb	Adverb
pitch blackness	Yes	No	No	No
total darkness	Yes	No	No	No

As nouns, pitch blackness and total darkness are synonyms defined as:

Other synonyms of pitch blackness include black, blackness, lightlessness.

pitch blackness (noun)	total darkness (noun)
total absence of light	total absence of light