We just rented The Mystery of Picasso from Netflix. This is a documentary by Henri-Georges Clouzot and shot by Claude Renoir (awesome). Picasso wanted this film to show his process, and the filmmakers use a number of techniques to do this. Picasso, shirtless and candid, paints on light boards so that the opposite view shows only the lines being rendered. There is also a series of stop phoography that enables us to see layers and changes involved. It's really neat to see Picasso work this way and to see what amounts to an animation of his paiting process.

The filmmakers are on camera talking with Picasso about how much film is left and how fast he will have to paint to get it all one reel. Their engineering is an interesting complement to Picasso's own.

I highly reccomend it.
P