montage vs photomontage

montage

noun
  • A composite work, particularly an artwork, created by assembling or putting together other elements such as pieces of music, pictures, texts, videos, etc. 

  • The art or process of doing this. 

verb
  • To combine into, or depict as, a montage. 

photomontage

noun
  • The art of constructing such images. 

  • A composite image combining two or more photographs. 

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