Tim Peake Caught CGI'ing it up During George Bush Senior Visit 🙈
Time 00:00 - 00:05. Watch The first 5 seconds of this video.
This video is self explanatory. NASA uses a white grid on blue screen chromakey as a backdrop to astronots pretending to be on the ISS. The astronots can conduct a live TV interview while pretending to play with objects in zero gravity. The objects are not real. They are CGI live renders composited using virtual reality technology.
The computer uses the white grid on the live video feed (angle and size of the white lines in relation to each other from the camera view) to determine the 3d spatial relationship, and composite the virtual 3D object (like a floating water blob) in virtual space with the astronots. The computer is programmed to register and track certain real reference objects, like the hands of the astronot, or a ping pong paddle, and it instantly creates virtual invisible 3D versions of these to replicate interaction with the CGI.
It’s simpler than you might think. The computer does all the work, based on pre-programmed physics.