Jerry Uelsmann - forerunner of photomontage. This guy was doing what we do in photoshop, but working meticulously in the dark room. He broke the rules of photography to develop some beautifully strange and surreal imagery.
Before Photoshop allowed image makers to bend reality to their will with a single keystroke there was Jerry Uelsmann. His layered images came from seven enlargers, multiple negatives and his own hands.