Meet the A-Team
An early sequence shows Hannibal (Liam Neeson) and B.A. Baracus (Quinton Jackson) coming to the rescue of Face (Bradley Cooper) with the aid of the iconic GMC Vandura. Shots of the van launching were achieved by special effects supervisor Mike Vezina. "The director wanted the van to be quite iconic and come up almost like the rising sun and be backlit. So we dug in a 30 foot ramp that we could adjust in height and then used a very powerful 10 foot ratchet to get the speed of the van from 0 to 45 km/h. As it lands, the stunt guy took over and slid the van out."
After recruiting helicopter pilot Murdoch (Sharlto Copley), the A-Team is then pursued in a dramatic helicopter chase, starting from a hospital rooftop. "We built a helicopter gimbal that had four degrees of freedom and rotors that functioned with electric motors on a crane," said Vezina. "The gimbal had a rotating pinion gear in the centre of it and then the arms supported a tilt forward and back. We controlled the crane using proportional valves and we put in some Kuper software to be able to repeat the moves." Movement of the gimbal went through a wi-fi joystick system that operated hydraulic accumulators. "What we do is stand right beside the director and show him the moves using the joystick, which uses remote signals beamed down to the main brain that opens and closes the valves. Once he is happy with the sequence, we then record the move in the Kuper software and let it run by itself."
Prime Focus' Vancouver office handled visual effects for the aerial chase sequence over mountainous terrain and a river under the supervision of Chris Harvey. For certain shots, one of the real helicopters, a Bell 205, was removed from the plate and replaced with a CG version that was built using Maya, 3ds Max and Mudbox, rendered through V-Ray and composited in Fusion. The shots also featured digital doubles of the A-Team, including B.A. who at one stage almost falls out of the chopper. "Replacing the helicopter was quite difficult because it was over moving water, but of course we had some great reference," said Harvey. "Our goal was to replicate the helicopter and the A-Team so that they could cut from shot to shot without the audience knowing it was going from live action to CG."
Other effects in the sequence included missile trails, smoke, water splashes and shots of the side of a cliff exploding, which were accomplished using a range of tools from FumeFX through to scripted particles setups rendered through Prime Focus' proprietary Krakatoa particle renderer. Close-ups of the actors inside the helicopter were filmed on a bluescreen gimbal stage on a rotisserie rig developed by Mike Vezina that could turn the entire cockpit 360 degrees with the actors for specific loop shots.
Kuwait base
Some years later, the A-Team is shown having successfully fought as a special ops team in Iraq. About 30 shots depicting a Kuwait forward operating base in the final days of war were delivered by MPC Vancouver, under the visual effects supervision of Erik Nordby, including an initial large reveal of the entire operation. "The base needed to feel like it was about to be torn down," explained Nordby, "but with a hive of activity of vehicles, planes and soldiers on the ground." Jamie Price provided MPC with some concept art while MPC began modeling a small number of CG assets such as Black Hawks, Chinooks, Humvees, walls, containers and towers, and modifying a C-130 model supplied by Rhythm & Hues.
Production shot a plate on a gravel road in Vancouver of a helicopter entering the frame with a subsequent tilt up designed to reveal the base. "Unfortunately, the surrounding area was covered by deciduous forests and obviously didn't look like Kuwait," said Nordby. With such a large area to achieve via visual effects, MPC approached the shot as a 14 slice matte painting that could be projected onto the tracked camera move. "It really helped us sell that feeling of depth. In the end the only thing we salvaged from the plate was the foreground helicopter and everyone else was CG."
For the ground, artists referenced examples of desert-based features from MPC London's recent film work. "Kuwait has some very specific land formations," noted Nordby. "It's more like a rock desert with a looser grey sand that's very fine. Sand dunes also didn't work because it felt too African." Along with roads, these desert features were matte painted in Photoshop, with structures, vehicles and aircraft added as completely CG geometry built in Maya or achieved using 2 1/2D projections in Nuke.
Trouble in Baghdad
Hearing of a plan to steal U.S. currency printing plates before the war is wound up, the A-Team go on a mission to retrieve the plates and a container truck convoy carrying billions of dollars. B.A., Face and Hannibal successfully ambush the truck as it passes along Baghdad streets, then through a tunnel and into the Tigris river, where they are met by Murdoch piloting a V-22 Osprey which subsequently carries the container back to a base. The sequence was shot on dressed Vancouver streets, docks and on bluescreen, with practical effects, including the launching of the truck into the river, handled by Mike Vezina.
Digital Domain contributed about 100 visual effects shots featuring a digital tunnel, Baghdad backgrounds, composites and gunfire. "I thought they did a really nice job of set-dressing the street," noted DD visual effects supervisor Kelly Port, "but we wanted to make sure that there were additional Middle Eastern elements like mosques in there off in the distance that helped make the skyline more realistic. We used Nuke for compositing and took advantage of Nuke's 3D capabilities. We could re-project some photographic backgrounds onto some geometry and then re-photograph it with the foreground camera so that they tied together much better - the perspective is lined up perfectly and tracks perfectly. We use that a lot to line up moving cameras to each other that haven't been shot motion control. For backgrounds, if they're far enough away we just put them on cards, but if they're midground elements we use rough geometry that allows for parallax and perspective shifts."
Digital Domain also completed shots of the truck crashing into the water and the arrival of the Osprey. "We had full water simulations for when the container hits the water," said Port. "The entire environment was re-created in Nuke - the river, the distant shore, the skyline, the city lights, the bank of the river. We kept it a little bit urban, with a concrete embankment." Artists built a CG Osprey in Maya and rendered the tilt rotor aircraft in RenderMan. "One of the things that was a challenge was that the actual tilt rotors move quite slowly. It takes 15 or 20 seconds to go from airplane model to helicopter mode. In the limited time of our action sequence, we had to make that all happen a little sooner."
Another of Digital Domain's challenges involved matching different film formats. "The film was anamorphic and the majority of the movie was shot anamorphically," recalled Port. "This particular sequence was shot spherical so that we would have room to move the image later, at least north and south, to help align the foreground or background better, or re-project onto geometry to help out perspective. The foreground bluescreen was shot on spherical film. The backgrounds for the bluescreen were shot Vista and some of the aerials were shot digitally with F-35 cameras. And then we had other anamorphic shots like when the Osprey later takes the container and drops it at the base. One of the general directives was to really mess it up, so we had a lot of flares and shaky cameras and lens hits, getting some spray onto the lens when appropriate. They wanted to keep it gritty like that - any kind of stuff like that takes it away from the 'studio' look."
Landing with the container, the A-Team find themselves caught in a set-up as the container full of money explodes - a practical effect handled by Mike Vezina's crew. "We took a real container," explained Vezina, "took the metal sides off of it, created a vacuform mould made of lightweight plastic and then we cut all the plastic pieces. There was a cannon that shot all the debris out and then the money comes from two big debris cannons. The actual end result was them being showered in burning money for like 10 minutes!"
The tank drop
Wrongly sent to prison for their part in the container heist, the A-Team eventually escape and seek to clear their names. Unsuprisingly, they commandeer a C-130 Hercules only to be engaged by Predator drones, but not before making it into a parachuted tank, somehow returning fire on the drones and using the tank's cannon to pilot it to the ground. Effects for the C-130 and tank drop were handled by Rhythm & Hues and supervised by Bill Westenhofer. A large part of Rhythm's work centred on the cloud environments through which the drones and C-130 weave.
"For the clouds," said Westenhofer, "we used Houdini to help create bounding volumes and then used a combination of cloud-scattering software and our volume renderer called Felt. Houdini handled the ray bouncing and occlusion detection and the internal lighting of the clouds. The animation team did a round of placing clouds using grey shaded models. We could then render that, see how it looked and then move them around. It was important for animation to do that because sometimes we had to mask an object and all that had to be available to the animators to control before it got to the actual render stage."
The C-130, tank and drones were modeled in Maya and then put through Rhythm's proprietary animation, rendering and compositing tools. "Because it was all CG and because the planes were relatively small compared to the clouds, we could actually generate an animating HDRI map for each plane," explained Westenhofer. "We set up a 360 degree camera and rendered all our clouds, so it was as if you had a video camera capturing an HDRI image from each plane and we used that as a standard HDRI lighting model. We were actually generating a new map for each frame of the shot and if the plane was inside the cloud for those frames, it would actually ray trace into our cloud environment and you'd get a fully grey surrounding HDRI map. So you'd get that moving through a fully diffused lighting environment and back out into sunlight, and that would all happen automatically."
Tracer fire and explosions as the A-Team shoot down the drones and receive fire themselves were achieved using Houdini's volume renderer. For shots of bullets hitting the tank's parachute, artists manually orchestrated the passage of tracer fire. "Once the bullets were done," added Westenhofer, "we determined where they hit the surface of the parachute, marked up those locations and passed those back to modelling so they could build holes where the bullets hit. Then procedurally the holes would pop open and wind forces would pop up through. Our tech animators would do hand animation to model the impact as the bullets leave ripples on the surface."
Close up shots of Face firing at the drones were filmed on a bluescreen stage using a tank gimbal - actually a modified flight simulator - constructed by the special FX crew. "We controlled the gimbal with a 1:1 macquette," said Mike Vezina. "The macquette is small enough for one person to hold in their hands. It has small cylinders inside of it and electronically captures the position of these cylinders, sends a message to the big cylinders on the tank gimbal and makes them move in real time. Once the director is happy with the movement of the tank on the gimbal, then we record the move and play it back."
Compositing was handled using several z-depth passes, as rendering all of the elements together proved to be too computationally expensive. Rhythm also added in atmospheric perspective and sometimes wispy clouds to help with speed and scale. "In addition," said Westenhofer, "there were a couple of places where you could see the drones emerging from the clouds and we wanted to show the effect they have on them. The fluid simulation generated some force vectors to get the clouds to twirl and move as the object punches through. We actually modeled a wind tunnel simulation over the surface of the plane to get the right vortex forces."
Earlier shots of the C-130 taking off from the airbase featured visual effects from Weta Digital working from a C-130 model provided by Rhythm & Hues, as its wings clip all the cockpit windows off a line of F-18s and a truck at the end of the runway. "It was pretty much straightforward animation, tracking the camera and making sure the tips of the wings would hit the canopies on both sides of the runway," noted Weta visual effects supervisor Guy Williams. "We had to get the right sense of acceleration and mass of the plane. You want it to go fast but you also don't want it to look like a small toy."
Frankfurt heist
Learning that the precious printing plates and the plate's sellers will all be at a Frankfurt bank at the same time, the A-Team execute an elaborate retrieval operation. In it, B.A. poses as a window washer before shooting a gas cannister into the bank to allow Hannibal to abseil in and grab a briefcase containing the plates and nab one of the sellers, who is subsequently thrown out of the building, complete with parachute, and stylishly caught by Murdoch via helicopter. Visual effects for the sequence were completed by Hydraulx and supervised by Chris Wells, who saw the digital doubles required for the scene as the biggest challenge. "We had a scan of the guy who gets thrown out the window," said Wells, "but that didn't really help us because he had a bag over his head. The hardest part was doing the 12 frame hook up between the live action guy and our digital double, then transitioning into a completely digital shot of the building, the ground, the helicopter and the parachuting guy."
Production shot plates for the sequence in downtown Vancouver to stand in for Frankfurt, with Hydraulx adding 3D buildings, augmenting real ones and finessing the shots with matte painted backgrounds. Animated trees, cars and some Massive agents as pedestrians rounded out the scenes. The helicopter was modeled in Maya and rendered in mental ray, while cloth sims for the character and parachute were completed in Syflex. "We hand animated the basics of the parachute popping and then sim'd the cloth on top of that to get that feeling of turbulence going through it," said Wells. "For the animation, it was a real balance between doing something so crazy but then also making it exciting and believable for the audience."
Shots of B.A. sliding down a building were achieved on location using Mike Vezina's high speed electric winch system and then augmented by Hydraulx, which added environments as well as broken glass using an nCloth sim in Maya. "We found that the cloth sim had a good way of making the glass appear right," noted Wells. "We made it look like safety glass, not plate glass. Also, we tried to do some matte paintings for views of the interiors of the buildings, but it didn't give the right perspective shifts, so they're actually all built in CG. When we're following B.A. down the building from right behind him, there was such a large amount of distortion going on that we actually had to animate the set to make the rooms fit in the plate - but no one will ever know!"
Containers and (more) explosions
The film's finale involves a showdown at Long Beach Harbour between the A-Team, who have arrived via cargo ship, and their adversaries. Seeking to create a diversion against the bad guys, the A-Team is eventually confronted by a rocket launcher fired into the side of the ship, causing mayhem as containers and their contents spill onto the dock. Mike Vezina supervised practical container explosions using an interior nitrogen cannon that could send objects sometimes 20 feet into the air, while Rhythm & Hues and Weta Digital handled visual effects for the sequence.
Rhythm & Hues completed some helicopter-type establishing shots of the cargo ship at sea and at Long Beach Harbour. For subsequent views of containers crumpling, the studio relied on Houdini as its rigid body solver and for all the simulations. "The rigid body simulation did one level of showing the containers crush into form," noted Rhythm's Westenhofer. "That worked for the most of the wide shots, but closer shots were hand animated to get the detail of the crushing. They had to spill contents sometimes so that involved simulations. We used our Massive pipeline to handle all the geometry. There were places where we had to create a fully synthetic environment as well, and we used our Rampage software for 2 1/2 D projections."
Weta Digital handled a number of the container sequence shots seen after a missile blows a hole in the cargo ship, including containers crashing onto the dock and large scale explosions. "We used Naiad to do a lot of the fluids and the water you see splashing at the base of the ship as it hits the dock," said Weta's Guy Williams. "The containers kick up big water splashes and that was all done in Naiad too." The studio also utilised rigid body dynamics software Bullet into their in-house tool wmRigid to simulate the containers hitting each other and spilling their contents. Explosions were rendered as fully 3D elements, enabling Weta to place their CG camera in any position.
"On the rendering side," noted Williams, "our team wrote a clever ray marching system that not only deals with volumetric lighting but also the temperature of the fluid sim itself. It actually deals with putting the colour of the fire into the fire properly and with all the proper absorption of light and shadows through the smoke. It really helped tie everything together."
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