clearness vs transparency

clearness

noun
  • The state of being free from obscurities or opacity; distinctness of light, colour etc. 

  • The state of being free from obstruction or interference. 

  • Mental or sensory distinctness; clarity of understanding, perception etc. 

transparency

noun
  • The quality of being transparent; transparence. 

  • Sufficient accuracy to make the compressed result perceptually indistinguishable from the uncompressed input. 

  • A transparent artwork, viewable by shining light through it. 

  • A translucent film-like material with an image imprinted on it, viewable by shining light through it. 

  • A transparent object. 

  • Openness; accessibility to scrutiny. 

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