In August of 1958, 57 of the greatest jazz musicians of all-time gathered on the steps of a Harlem brownstone for a photograph. The Academy Award-nominated 1994 documentary "A Great Day is Harlem" is a film about possibly the most famous photograph in jazz history. It is also a love note to this art form. The musicians in the photo represented the full spectrum of jazz history from Dixieland to Big Band Swing, from Harlem Stride, to Modern Bebop. Sidemen, innovators, young lions, and old masters were all there.