December 13, 2013 8:00am PT by Carolyn Giardina
'The Desolation of Smaug:' Weta's Joe Letteri Reveals The Biggest VFX Challenges
The most challenging visual effects in Peter Jackson's The Hobbit: The Desolation of Smaug—which could reach $80 million this weekend when it opens in North America—will be revealed when Bilbo Baggins enters the former kingdom of Erebor in the Lonely Mountain, and finally comes face to face with the dragon, Smaug.
“He’s huge, twice as big as a 747,” related VFX supervisor and four-time Oscar winner Joe Letteri of Weta Digital. “Peter wanted his physical size to dominate. Then we had to figure out how to build the environment around him, so he had the room to move. It was like the size of Monaco.”
The key to the scene, however, were the performances. Letteri said they were approached in a similar way as the "Riddles in the Dark" scene from An Unexpected Journey during which Bilbo plays a dangerous game of riddles with Gollum. "Bilbo engages with Smaug in the same way, to just keep himself alive and see how he can escape,” Letteri said, adding that it was treated as a dialog scene.
But in a setting filed with heaps of gold, the challenge of each movement was magnified. “We had to simulate all the gold coins, every time he moved,” Letteri said, noting that Weta wrote new software to accomplish this type of simulation. “Sometimes it was a little, sometimes it was a lot, but it ended up being over a billion [CG] gold coins. During some of the action sequences, threre were hundreds of millions of coins moving at once.”
The team added tarnish since the coins were said to have been there for hundreds of years. “We also had to ray trace everything to get the way the light was bouncing off of them,” Letteri said. “ The lights sources themselves had be hidden since they were underground.”
The dragon itself was created with key frame animation (meaning it is animated by hand), and features the voice of Benedict Cumberbatch.
To create a realistic creature, Weta employed its proprietary "Tissue" software that earlier this year was honored with a Scientific and Engineering Award from the Academy of Motion Picture Arts and Sciences. “We used the system to create muscles and figure out what his neck would be doing or his shoulders. He uses his shoulders like arms, but they are also wings, which complicated the rigging.”
Another complex scene was a chase that involved the dwarfs traveling through river rapids in barrels, required a lot of water simulation. “We couldn’t shoot a lot of what we needed to do," Letteri said. "We found bits of river that we could use, and did some of it [live action] in a waterway that we build, but a lot of that action had to be created digitally—the water, the characters, the environment. For the more frenetic stuff we threw barrels in the water and would put digital doubles in them.”