What is performance capture'
Where an actor’s movements and expressions are electronically tracked and translated into computer generated imagery (CGI) to bring a character to life. One of the advantages of performance capture is that it is less about technology and more about actors.
How is it done'
Digital sensors are attached to an actor’s face and bodie via a form-fitting lycra suit, so that the live performance is “captured”, to be put into a computer. All the action takes place in an invisible box called a volume, which is divided into quadrants that can house as many as 40 cameras. (The volume is performance capture-speak for soundstage and is so called because it allows multiple cameras to photograph the scenes in a three-dimensional space. The classic geometric formula for “volume” is x, y and z, representing width, height and length). Specifically, a volume is the area where the cameras are all aimed, within which face and body data may be captured. Takes or “beats” from multiple capture sessions can be edited and blended, mixed and matched and the result can be a compelling new medium that is not at all “cartoony” but rather tethered to the actual creative expression of the actors and director.
How has it been done in Beowulf'
Academy Award-winning director Robert Zemeckis tells the oldest epic tale in the English language with the most modern technology, advancing the cinematic form through digitally-enhanced live action. With Beowulf, Zemeckis was ready to take the technology to the next level. “When you do a performance capture film you have the ability to do two forms of casting, one for performance and one for likeness, which means you can actually separate what a character looks like in the film from the performer who portrays that character,” says Steve Starkey (producer). “It’s one of the reasons we decided to do the film in this style; for instance, no one on the planet looks like the character envisioned for Beowulf or could perform on the level wanted for this film. Beowulf is larger than life and there is no single human actor who embodies everything in the character. So, how do you blend these two irreconcilable aspects' By casting the best actor possible and creating that look, a six-foot-six Christ-like image in the computer. The same is true with Grendel. If we were doing Grendel in a traditional film, we would have had a 12-ft puppet on set and created additional computer graphics. In this case, we could get the perfect performer, who portrayed all of Grendel’s pain and suffering but wasn’t limited by prosthetics or uncomfortable suits,” says Starkey.
Executive producer Avary adds that performance capture realised the film the way he had always envisioned it and, in addition, it presented an almost limitless canvas. “The interesting thing to me was that the performance capture process really allowed the film to be performance-based. I had always seen it as a chamber piece — it’s in court, and there’s intrigue between people with their myriad relationships. I always wanted it to be a fully formed, emotional experience. We weren’t restricted by anything,” Avary notes.