Re: how to make objects spread out in 3D space look connected with moving cam?

I know that there ARE such things as greenscreen treadmills... No idea what they would cost to hire, and I wouldn't expect it would be particularly easy to convert one yourself (or cheap, for that matter: you'd probably have to cover the whole tread in greenscreen fabric, which itself is expensive)...

You could try using a regular treadmill, then create a loop (try morphing techniques) of the subject walking that's just long enough so that people won't notice that it's a loop, but just short enough that you don't decide to shoot yourself before you finish rotoscoping around her feet on each of the necessary frames...

Good luck,

DP