THE AVENGERS VFX Supervisor Jason Smith Talks Stark Tower, The Helicarrier And Hulk

We had never created a digital city on this scale at ILM [Industrial Light & Magic] before, so it was certainly a humongous challenge to undertake. However, it was also something we were looking forward to working on because it's such an iconic movie. The first step saw us look at the pre-vis for the movie, which is when we realised that the action occurs in different parts of the city. We got a map of New York and Marvel's visual effects supervisor led us through the process where we decided which buildings we'd see in the movie and which streets we'd see characters like Iron Man fly down. We sent four teams of staff to New York for eight weeks to shoot the photography needed for the project. Each team was four or five people, and it was a massive undertaking. They shot 275,000 photographs - and we stitched these photos together to create a VB sphere. Originally, I think they planned to shoot in New York for a month or so, but they ended up spending three days there. They shot part of the scene where the Avengers stand on the viaduct in New York, but it was cut back and forth with green-screen shots. They actually filmed a lot of that scene in an abandoned train station in Albuquerque with green behind them.

I was heavily involved in that process. Stark Tower stands where the MetLife building stands in Manhattan. Marvel developed a look for the tower and they gave us a design that they were very happy with. They went into a lot of detail and had even figured out what kind of materials they want it to be made from. We created the building using CG and slotted in over the MetLife building in our virtual landscape. We started out with a pretty simple building, but it ended up being incredibly detailed. We added the tiniest of details, such as handrails and streaks on the window's glass. Stark Tower was very difficult, but I would also say that the Chrysler building was a challenge because it's got such a distinctive look. People know exactly what it looks like and we were going to get very close up to it with Thor standing right there on the building. That was probably one of the toughest challenges for us in Manhattan.

I did a lot of work on the Helicarrier, and the big challenge with that was scale. All the time, we were trying to make sure that this thing looked like an aircraft carrier, so we examined pictures of aircraft carriers and we tried to fold in a lot of the same details. To get the scale right, we had to put jets and helicopters on there, as well as people to see how big they would appear. We were lucky that they had actually painted the Avengers symbol on a runway in Albuquerque. They filmed a lot of the Helicarrier deck scenes right there. A helicopter flew around the location and shot a lot of the action, so we then took out the dirt next to the runway and replaced it with water. It was a great way to do it because they placed real jets on the sides of the runway and then we added two or three times that amount of CG jets, leaving the real ones in place. When you watch the movie, you can't pick out which one is real. To be totally honest, I think we referred more to real aircraft carriers and battleships because the design had been pretty well worked out by Marvel. They knew what they wanted, so we just had to bring it to reality and make sure that the scale worked.

Our biggest challenge involved the creation of the Hulk. We knew we had to nail that for the movie; we had to get it exactly right. We had an actor that everybody knows - Mark Ruffalo - playing a big character that everybody loves. The Hulk is my favourite character in the whole Marvel universe, so I was adamant we'd get him right. Hopefully, we pulled it off. Mark was amazing. We put him through hell when we were creating the Hulk because we had to scan his entire body. At one point, we asked to shoot the corners of his eyeballs. We had him spread his eyes open and look to one side. When we've created digital creatures in the past, these are the assets that we never had and we knew we'd be able to improve our design with them. This time, we made a big list of everything we needed, including the insides of the fingers and his armpits. Hulk has a couple little scars and those are the little things that come straight from Mark. It was great that he was so helpful. I think it comes across on screen because the Hulk looks amazing.