Two years ago, "Avatar" defined the state of the art in 3-D moviemaking, becoming history's top-grossing film and winning a visual-effects Oscar in the process — so how is the "Avatar" team going to top that for "Avatar 2," "Avatar 3" and beyond?

"I'm overhearing some things that are really exciting," actor Giovanni Ribisi, who played the corporate bad guy in the sci-fi blockbuster, told me last week during the opening of an "Avatar" exhibit at Seattle's EMP Museum.

For example, part of the action in one of the sequels will take place underwater, which poses big challenges for live-action filming as well as computer-generated graphics. Film director James Cameron, who pioneered the use of 3-D cameras for underwater documentaries, is reportedly having a high-tech submersible built for doing the sequels. And special-effects wizards are already working with Cameron to flesh out the underwater habitats of Pandora, the fictional alien moon where the action in "Avatar" takes place.

"He wants to see what's under the water, so we're going underwater," said Richie Baneham, animation supervisor for "Avatar."

Beyond that, the special-effects team has pretty much kept mum about what shape the sequels might take. But during a panel presentation held in conjuction with the Seattle exhibit opening, they made clear that they plan to keep pushing the wave of technological innovation that made "Avatar" possible.

Among those innovations is the Simul-cam camera viewer, which combines computer-generated graphics and live action in real time to show filmmakers more precisely what they'll see in the finished footage. (The technology is demonstrated in the video clip above.) Cameron also used a motion-capture technique that created detailed 3-D renderings of the actors while they were being filmed — a process that "Avatar" actor Laz Alonso said he appreciated greatly.

"As an actor, you usually have to save energy for the close-up," he told me. "With this technology, you can go 100 percent, all in, every single take, because you're being covered 360 degrees on every take."

Nolan Murtha, the digital-effects supervisor for the virtual production unit on "Avatar," predicted that 3-D movies eventually will be made using holographic technology — although it might take a while. "It'll probably be eight years before you'll see really credible results with holograms," he said.

"And I have no doubt Jim will be the first to make a movie with them," quipped Yuri Bartoli, supervising virtual art director for "Avatar."

In the shorter term, Cameron and the "Avatar" special-effects team are concentrating on ways to make the 3-D moviemaking process more like, well, regular old 2-D moviemaking. I asked Murtha about the technological path between "Avatar" and the age of holograms, and here's what he had to say:

Nolan Murtha: "With 3-D being an emerging technology right now, it's really starting to find its way into the consumer market and into the home. I think it will be our task for the next four or five years to develop that technology, and then to also evolve more interactive displays and more volumetric displays. The holographic stuff will be another revolution that I'm really looking forward to."

Q: Do you feel as if you have the tool set for that 3-D era, or do you think more tools have yet to be developed?

A: "We want to allow photographers and production designers to work with digital environments and digital tool sets, but using traditional filmmaking tools. So we want to re-create realistic lights, for example, and give filmmakers the same tools that they would have on a live-action set — in a virtual environment, in a virtual world.

"We're employing a lot of technology, but it's really to get back to a traditional filmmaking experience for the people who are doing the work. We're removing the computer nerd in the corner in the darkened lab, working on the content and then having the director look at it. Well, now the directors and the designers can start to do it themselves. They're directors. They want to do it themselves." 

Q: How far are you on that road? Are there things that really need to be developed yet in order to do what needs to be done for the sequels and for other projects?

A: "Yeah, we are always working, we're always looking at new technologies. I'm going to China to look at some brand-new stuff that they're doing over there. We want to employ whatever technology we can, and we want to be constantly evolving and making ourselves better.

"Three weeks after 'Avatar' came out and it was breaking all these records, we were actually sitting at a table with Jim and Richie and all, and we were talking about what we screwed up, what are we going to do differently, what did we do wrong. We pointed out all of our flaws even as the movie was breaking all these records. So we're constantly re-evaluating what we did, how we did it, and the mistakes that we made. That's important. To stay on the bleeding edge, you have to recognize that you are making mistakes and then adjust."

Q: Can you talk about what you're looking at in China?

A: "No, I can't."

Q: But does it have to do with this sort of filmmaking?

A: "Yeah, real-time graphic technology and some holographic stuff ... but I can't really talk too much about it yet."

Q: This is something we might see sooner rather than later?

A: "Oh, yeah. We hope so."

More about 'Avatar' and the future of film:

• 'Avatar' director targets spaceflight
• 'Avatar' gets top billing at Seattle museum
• The future of the movies is wearing 3-D glasses
• Virtual actor takes over in 'Tron: Legacy'

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