Special effect in scene with Hungry Joe (spoiler)
There is a well-known scene in which McWatt, flying an airplane at low altitude in an attempt to scare Yossarian, accidentally chops Hungry Joe in half, who had been standing on a platform in the water. In the scene, we see Joe's legs (minus the rest of his body) pause for a moment and then suddenly fall into the ocean.
If Catch-22 had been filmed today, this special effect would almost certainly be done in post-production with computer imaging, but of course such technology did not exist in 1970. It is quite remarkable, then, that the filmmakers were able to produce such a convincing effect, and I wondered how they pulled it off.
Switching to the commentary track of the Catch-22 DVD, I skipped to Hungry Joe's final scene and was delighted to hear one of the filmmakers explaining the secret behind this special effect. Unfortunately, I couldn't understand his explanation!
He said something about a projection, that the actor playing Hungry Joe was simply holding up a screen. Indeed, when I stepped through the scene frame by frame, I noticed that there seemed to be a kind of halo around the area where the actor might be holding a projector screen.
But this still doesn't fully explain how the special effect was done. Was the projection onto the screen simply an image of the landscape behind Hungry Joe? That makes sense, but how were they able to mask the actor's top half when he fell into the ocean? If he were holding a screen, it seems like it should have been visible at that point.
I don't quite get it. Can anyone explain it to me?