http://www.variety.com/article/VR1118043598?categoryid=3996&cs=1&cmpid=RSS
On “Avatar,” the vfx team at Weta couldn’t directly import the “template” footage that came from the virtual shoot. Instead, they’d have to re-create the digital scenes and characters from scratch. On the sequels, Weta will be able to bring that template in as a low-res version of the scene and start working on upgrading the image without having to start over.