[on why using conventional rigs wouldn't have worked in filming 'Gravity']I think there are two reasons. It would work for a period of time but not for the whole movie because you can see the wire. You can sense it on traditional wiring certainly, but even on a heavily developed one you can just tell what'd going on. There are certain moves you just can't do on a wire rig, the wires just get in the way. But also because Alfonso has very long shots. It couldn't get you a long shot. It would just be impossible to manipulate.