My wife bought me a great book on the life and work of JC Leyendecker (1874 - 1951) for Christmas last year. I've been a huge fan of his work since the first time I saw it back in college. His paintings are so clean and well designed, and he made it look so effortless. Unlike Norman Rockwell and many of the illustrators that followed him, he did not use photo reference at all, but did careful studies of props and models from life for each of the illustrations he created. I decided to do regular studies of his work in hopes to unlock some of secrets hidden in his flawless technique and better understand his thought process.
Leyendecker was a master at painting hands full of character and personality. In doing this study from one of his preparatory paintings, I could see just how much he utilized the ground as a mid tone to work back and forth with darks and lights. The ground is a light gray and since he keeps the shadows thin, the overall effect is very luminous - a hallmark of his paintings.
Anyway, the top image above is the study I did, and a process sequence. The painting was done with Photoshop CS3. The bottom image is the Leyendecker study I was working from.