chroma vs tempera

chroma

noun
  • The colorfulness relative to the brightness of a similarly illuminated area 

  • The aspect of a colour's hue that depends on the amount of white or black in it; saturation 

  • A note in a chromatic scale 

tempera

noun
  • A medium used to bind pigments in painting, as well as the associated artistic techniques. 

  • A painting done in this medium. 

How often have the words chroma and tempera occurred in a corpus of books? (source: Google Ngram Viewer )