January 1, 2010
By Nazir Keshvani
James Cameron’s Avatar achieves several milestones in filmmaking technology. Cameron wrote his first treatment for the movie in 1995 with the intention of pushing the boundaries of what was possible with cinematic digital effects. In his view, making Avatar would require blending live-action sequences and digitally captured performances in a three-dimensional, computer-generated world. Part action–adventure, part interstellar love story, the project took 10 more years before Cameron felt film technology had advanced to the point where Avatar was even possible. Cameron needed to invent a suite of moviemaking technologies, push theatres nationwide to retool, and imagine every detail of an alien world. With an estimated production budget of US$237 million, the technological mix of real actors and computer-generated imagery (CGI) that is digitally manipulated by originals artists who portray their characters in a studio environment. In addition 3D computer graphics software are used to simulate the imaginary landscapes of the land of Pandora. The characters created with CGI are seamlessly integrated, along with real actors in studio settings into live action scenes. If 3D is the future of movies, the question is how to generate animation inputs that have to be very realistic. The answer lies in performance capture technology. CGI characters have to act and behave like real actors and this has been made possible by performance capture technology. Through this technique, inputs taken from real human actions of Sam Worthington and Zoe Saldanha in the studio settings are fed as input for computer animations of Jake Sully and Neytiri respectively. Motion capture is a technique by which live actions of real actors are recorded to be the inputs that control and manipulate a digital 3D character model. When it goes beyond simple hand, legs, head and body movements to capture subtle facial expressions and finger gestures, then it is referred to as total performance capture. For example, Worthington’s fearful expression when he encounters Pandora’s wild life being shown on his avatar and Saldanha’s gentle touch of her pet ikran the Banshee, captured as Gigabytes of data per second of action through their skull caps and leotards covered in sensors. Worthington and Saldanha work in an empty studio amidst grids so that their performance could be recorded by sensor-based digital capture systems. Later they are replayed on to the models of Jake and Neytiri. Pandora is a distant moon civilized by the Na’vi amid its exotic luminescent living forms. With three feet beings and hanging mountains, it is impossible to dissect what could be real from sets and what is animated in the entire movie. The studio shoots are done in a 16,000 sq.ft film set with a green paint on its inside walls. While most actions takes place in this set-up Pandora, the action scenes are shot amidst a computer-generated lush jungle environment in New Zealand with real actors, robotic animals and plant species. James Cameron’s stereoscopic cameras that each use a pair of lenses built to mimic human eyes capture images with a sense of depth. The mix happens later in digital studios where shoots are merged and appropriate sound effects are added. While previously cameras did exist to make 3D films, the making of the Avatar has resulted in the invention of an agile 3D camera system for 3D cinematography. Cameron used his own Reality Camera System that employs two high-definition cameras in a single camera body to create depth perception in 3D. This camera rig is significantly lighter and the two camera lenses can dynamically converge on a focal point with the help of a computer, which is crucial for sweeping camera moves and action sequences. The 3D version requires special 3D projection facilities and the audience are also required to wear polarized glasses for viewing in 3D.