[Empathetic1636] “I am curious with everything added to that shot….why does only the bus have green screen on it? Is it because it is moving?”
Yup. Because the bus is moving you’d want to be able to track the part of it where the video plays. And since this area is independently shaped from the bus, it’s best to create an area for tracking. I doubt that the green area was used for keying – more for tracking purposes. Once tracked, one could use the perspective tracked points to create mattes.
They would also have to track two different rectangular shapes to crete the effect that you see. Some simple extrapolation of the tracked data would yield the numbers for the two overlapping tracked areas.
The buildings are stationary and the area where video is to be composited is essentially shaped according to the building. So there is no need to have additional tracking information.
Cheers
Roland Kahlenberg
https://www.broadcastGEMs.com – Adobe After Effects project files
https://www.myspace.com/rorkrgbspace