From her years with Stieglitz and her interest (through Stieglitz) in modernist photography O’Keeffe began doing large–scale painting of flowers, leaves, and trees, close-up views of natural forms, paintings imitative of a camera’s close-up lens. The impression is of the eye or lens piercing the depth of the subject. This style is evident in the 1931 painting Horse’s Skull with White Rose and the 1939 work Pineapple Bud. The pineapple painting was a request of the Hawaiian Pineapple Company (Dole) wanting two paintings for use in advertising. Though O’Keeffe spent nine weeks in Hawaii painting the local scenery, it was not until later that she painted the requested pineapple, after the company sent a plant to her New York studio.
(http://wwwscriblets-bleets.blogspot.nl/2011/05/faraway.html)