The title of these sets of studies suggest some kind of picture-pieces, but Rachmaninoff never wanted to disclose what he had wanted to depict, but said that he preferred to let the pieces “paint for themselves”. Op. 33 was originally meant to comprise nine pieces, but the composer decided to publish only six of them in 1911.
Numbers three and five were published posthumously; number four reappeared as Op. 39 No. 6. Op. 39, published in 1917, is the last substantial composition written by Rachmaninoff while still in Russia. It’s clearly influenced by Rachmaninoff’s younger contemporaries Prokofiev and Scriabin.
Rachmaninoff had studied Scriabin´s works intensely to prepare a memorial recital (Scriabin died in 1915).