unsharp vs witless

unsharp

adj
  • dulled or intentionally blunt. 

  • out of focus; blurry. 

verb
  • To sharpen (an image) by creating a blurred ("unsharp") negative as a mask, and then combining that mask with the original. 

witless

adj
  • indiscreet; not using clear and sound judgment. 

  • Lacking wit or understanding 

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