We did some Baron levitations for the DVD release. (The DVD has a fair amount of additional material, so you may want to see it!) The actor and background plates were, again, shot without motion control, with the cameraman just trying to duplicate his move. He actually got pretty close, but still there were so many variations in the motion and perspective from frame to frame, that any simple split screen was impossible. We cut the Baron out and dropped him in the empty set, which worked fine as he was flying and slippage wasn't noticeable. But for Feyd, we had to go through a very complex stabilization of one plate to the other, then tweak by eye to eliminate any size and position variances. And then, we had to add a ceiling, by tracking the corners and pinning the art to that.