It's "that tiny little film that Jim did". That's how Framestore, London executive VFX producer Tim Keene affectionately describes James Cameron's box-office smashing, awards-raking and critically-acclaimed stereoscopic 3D (S3D) feature Avatar.

Since its release in early December, Avatar has gone on to become the highest-grossing film of all time in North America and in 29 other markets worldwide, not least in part to being the first film out of the gate to offer an in-cinema S3D experience.

Framestore was one of the VFX companies - alongside Weta Digital, Wellington; Industrial Light and Magic, San Francisco; global post house Prime Focus; and Blur, Venice - awarded scenes on the film. In particular, the post company worked on three major sequences: protagonist Jake Sully's arrival at Hell's gate, the military-industrial landing field located on fictional moon Pandora; the team's night-time escape from Hell's Gate on the Samson tiltroter aircraft; and Sully's initial conversation with Colonel Miles Quaritch on the Armor Bay, in which Quaritch dons the AMP suit, a four-meter tall robotic exoskeleton.

Ahead of the Academy Awards on Sunday, March 7, where Avatar will contend for nine golden statuettes, Keene spoke with Boards about working with the bespoke technology that Cameron created for the film; which scenes provided the biggest challenges and how "friendly" was the friendly rivalry between the post houses.

It seems there was a sharp learning curve on this film, not only with the stereoscopy but with Cameron's bespoke technology. Can you describe some of that tech, the challenges it presented and the ways in which Framestore worked to adapt to it?

When we first looked into Avatar and the idea of working in stereoscopic imagery, it was daunting, unknown and twice the amount of work. But once we started looking into it and certainly before we embarked on the bidding process we quickly understood that the principles behind it are relatively simple: you have two images shot, you do two renders and you deliver two images.

We were delivered two streams: one for the left eye and one for the right eye that were pretty evenly matched at that point in the process. We were given some very specific, highly-detailed visualizations, which [Lightstorm Entertainment, Cameron's production company] called Viz-Viz. It gave you an idea of the lighting [as well as a good animation and layout base]. So instead of a traditional pre-viz, this is worked up where if it involved live-action they'd roughly camera track material. The lab down at Lightstorm had also put in stock animation - or approximate animations - to get the framing correct. At that stage, it was populated with a lot of the correct assets at very lo-resolution so you had a feel for how Jim wanted the shot to end up. It was to the extent that if you stepped away from the Viz-Viz template, you would feel the wrath of Cameron!

The one area where we invested in terms of hardware and software at Framestore was stereo-viewing capabilities. We had the principles of producing the imagery but how on earth do you review it on a very quick, daily basis? You don't always want to go into the cinema - and we certainly did invest in getting our cinema equipped with a RealD projection system - but we also wanted to look into ways that you could view very quickly. We went down a couple of avenues. We looked at the Active Shutter glasses system, where the individual artist can have a pair of LCD shutter glasses synched with their monitor, which was okay for some of the work. But we end up primarily using the True 3Di viewing monitor, which we've affectionately called the ‘puppet theatre'. It's literally like a deep box monitor with two viewing screens that reflects onto a mirror and you view it with passive linear polarized glasses. It plays back very well and it's ideal as a viewing monitor for an artist to review their work - it's very stable.

Of the scenes that Framestore worked on, which presented the biggest challenge or required the most creative solution?

The Hell's Gate environment on Pandora in which we see Jack arriving very early on in the feature. That sequence has a bit of everything in there: complex digital matte paintings; complex full CG geometry; interactive effects elements: smoke, rain, water droplets. You've got motion capture animation for the digital doubles; you've got the digital doubles themselves...

It was a challenge because aesthetically there's a vast amount of assets. We generated about 400 separate assets for that scene. We were the lead house on the environment so there was the pressure to develop and get the look signed off as quickly as possible and hand the assets to the other companies, which had scenes involving Hell's Gates to a lesser extent than Framestore's shots.

That said, it still involved a lot of pre-built assets - the aircraft had been pre-built by Weta. So there was that additional factor of bringing in their assets and making sure ours were compatible with what had already been established, while developing our own look. It can inherently complicate things but you always had to be aware of what [the other post houses] were doing away from you.

How competitive did the friendly rivalry between the companies get?

It was healthy. Everyone had a huge amount to do in the time and I wouldn't say we had a walk in the park. I'm not sure anyone did. It was an unsaid rivalry. We were the lead on Hell's Gate. You wanted to get the sign off on that environment from Jim as soon as possible because then you knew you were going in the right direction if you got Mr. Cameron's approval. But also if you locked that down you were not having to match to someone else, which when it comes to shared assets and environments is key.

We had a couple wins and a couple of losses, all the companies did. One of our big wins was in the Armor Bay sequence when Jake is talking to Colonel Quaritch. When we showed a development shot of the AMP suit that Quaritch was in I got a really fantastic response from Jim who said that's the way he wanted it. He was very vocal that he wanted that shot to go out to the other companies to match it. It was great because most importantly we locked the look down so we could roll that out across the rest of the scene. Of course there's the professional pride that you've done something that other people have to match to. But that said, we were all in it together.

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