For the majority of his decades-long career, Norman Rockwell relied on a camera to help him render the iconic scenarios born in his imagination. Photograph by photograph, he painstakingly assembled the specific features he sought for his envisioned illustration, projecting whole or partial pictures of amateur models, objects and settings onto drafting paper, and from there, onto canvas. Many of Rockwell's most famous works - including those reproduced for LIFE and the Saturday Evening Post - began behind the lens. Uncanny in their approximation to his final paintings and unknown outside a small circle of Rockwell specialists, his study photographs are among the most evocative ever taken by a painter and undoubtedly cast his brushwork in a new light.