电影《阿凡达》创历史需感谢3D技术

Jake Sully is a wounded warrior: a U.S. Marine paralyzed from a battlefield injury. The chance to walk again is what initially draws him to a distant, dangerous moon.

"You are not in Kansas anymore. You're on Pandora. Out there beyond that fence every living thing that crawls, flies or squats in the mud wants to kill you and eat your eyes for jujubes."

It seems Pandora is the only place in the galaxy with deposits of a valuable new energy source worth untold millions back on Earth. To get it, however, they have to go through …or get rid of …the Pandora natives: a tall, blue-skinned tribe called the Na'vi. That's where Jake and his colleagues come in:

"Me and Norm are here to 'drive' these remotely-controlled bodies called avatars. They are grown from human DNA mixed with the DNA of the natives."

With his mind electronically linked to his Avatar body, Jake not only can walk again and survive in the toxic atmosphere of Pandora, he can also make direct contact with the Na'vi. That doesn't exactly go well at first.

But as the exotically beautiful Neytiri teaches Jake about the Na'vi and their connection to their world, he becomes convinced that the exploitation by his fellow humans must be stopped.

New Zealander Sam Worthington plays Jake and New Jersey native Zoe Saldana is Neytiri. Canadian-born Cameron spent years developing a 'performance capture' technology for their Avatar characters. The actors wear high-tech outfits dotted with sensors that record their every movement including the subtlest facial expressions.

"The whole thing we were trying to develop was about keeping alive and without any dilution the actors' work," Cameron says.

Cameron explains that those captured performances are the key to making the CG or computer-generated digital characters that audiences see come 'alive.'

"I don't want to be an animator. I don't want to try to figure out how to make the characters behave later through animation. That's not what I do. I work with actors," notes Cameron. "My proposal to the actors was: 'okay, we're going to be in a room [and] we're going to do this strange thing, but every molecule of what you create will be what your character does. I want that to be the performance that is seen two years later in the finished film.

Cameron also pioneered a realistic 3D technology that requires the audience to wear special glasses; but Sam Worthington says it puts them with him in the action.

"You are more endeared to these characters by feeling you are in the fight or the battle or the tragedy with them," Worthington says. "By doing that, the veneer of remembering it is a CG character starts to dissolve and you see the spirit. We were never going to lose our jobs because the CG character can only work if it is embodied by us and I can tell you that is 100 percent Zoe and 100 percent my performance. It is not a cartoon. We are not standing at a lectern voicing it. We had to do it so every jump and smash and roll and smirk and glimmer and kiss we did. That's the trick and the magic of this movie that Jim and WETA Digital had to push themselves to get to the point where we forget we are watching big, blue people and we start just rooting for the person inside them."

Writer-director Cameron also acknowledges that what the humans try to do on the fictional Pandora is a clear metaphor for what he believes are the dangers of exploitation on our own planet; and he believes that is warning science fiction can deliver:

"Science fiction can operate on many different levels. It can operate as a cinema just purely of the visual …purely of imagination; but historically the kind of science fiction that I grew up on had a message," Cameron says. "Usually it was a dystopian message in the form of some kind of warning; and I think that science fiction became more escapist fantasy and less a warning or intellectual medium. I think that Avatar was an attempt to merge science fiction back to its roots of having a warning."

"They have sent us a message that they can take whatever they want. Well we will send them a message …that this is our land!"

Avatar also features sci-fi veteran Sigourney Weaver as the scientist who creates the program to learn about and understand the Na'vi. Giovanni Ribisi plays the corporate manager of the Pandora mining project with Stephen Lang as the paramilitary commander of the human forces and Native American Indian actor Wes Studi is the Na'vi chief. The soundtrack music is composed  by James Horner, whose previous collaborations with James Cameron include the multiple Oscar-winning Titanic.