I was previs supervisor on the show, and the person interviewed in the article. It was a challenging job for a variety of reasons, but I was really pleased with how closely it matched the final shots.

The previs we did for 2012 was created for two purposes: first, to help the director and others explore the story and come up with an exciting way to show the action that took place in the sequence; and second, as a sort of proto-effects design, to help the VFX supervisors plan the look and timing of the effects elements that were going to be created for the shots. I've done more technical previs for other films, where we have generated shooting diagrams for the camera crews and figured out green screen placements, but this job was much more about telling the story than the practicalities of shooting it.

The storytelling part of the process was very fluid, with lots of changes. We started with a script and storyboards for our sequence, but as we generated versions of the previs, the director and other creative leads saw different directions they wanted to take the action and we had to adjust our sequence accordingly. We had a fair amount of time with the director in the early stages, but as he became more busy with other matters, our main point of contact was the VFX supervisor. He had a good sense of what the director wanted, so we spent a lot of time with him trying different camera angles and different ways to stage the action. It was really important that the animators set up their scenes knowing in advance that the action might have to move to another part of the location later, so changes could be made quickly and with a minimum of fuss.

The technical side of the project was challenging for a couple of reasons. First, we were helping the VFX supervisor design the look of the effects in the sequence, which is difficult to achieve when you are limited to previs-quality assets and very rapid turnaround times. We ended up "cheating" several shots, by adding canned elements on 2d cards into our scenes, etc. Second, the quality of previs that the production was asking us to produce was quite high: we had to add shadows, motion blur, depth of field, etc., all of which we weren't really prepared to deal with when we first started. It was a case of constantly trying to balance the fast turnaround vs. the high expectations. The high level of the outputs made it more difficult to turn around story changes quickly, because each shot had to be rendered and composited rather than just playblasted from inside maya. If I was to set the same job up now, I would look at some sort of GPU rendering solution so we could achieve that sort of effect without all the overhead.

Luckily I was working with some very talented people who were comfortable in that sort of environment. I work for Image Engine Design in Vancouver, and I was able to pull people from there out to the film studio when I needed an extra compositor or someone who knew fluid effects. I think that for previs, having a crew of people who are really adaptable and who actually enjoy working in such a constantly-changing environment, where the goalposts are shifting every day, is much more important than having rock-star animators or effects TDs.

I hope I was able to answer your questions!

We do show previous work and try to get a feel for what the clients want before we start, but I don't think there's a 'fix' for this issue. Client expectations change, often for reasons beyond their control, and we just have to be adaptable. We've had jobs that morphed from pure showcase previs into pure technical previs, and shows that morphed from technical previs into showcase previs. That's why it's important to have people with a range of skills on your team, but who enjoy working in a constantly-changing environment.

Because I work for a larger studio rather than freelance, the budgetary concerns are something I don't have to deal with. I do think, however, that it's important that everybody, including the producer, knows what work you are being asked to do, and how the changing situation is going to affect their bottom line.