By TREVOR HOGGImages courtesy of DNA Films, A24 and Cinesite.What starts off as a routine military operation goes horribly wrong, and such an experience left a lasting impression on former American Navy SEAL Ray Mendoza, who recounts how his platoon came under fire during the Iraq War in 2006 while monitoring U.S. troop movements through hostile territory. The real-life incident serves as the basis for Warfare, which Mendoza co-directed with Alex Garland and shot over a period of 28 days at Bovingdon Airfield in Hertfordshire, U.K. Assisting with the environmental transformation consisting of approximately 200 shots was the visual effects team led by Simon Stanley-Camp and sole vendor Cinesite.Im delighted and disappointed [that Warfare has been praised for its realistic portrayal of soldiers in action] because no one knows there are visual effects, and there has been nothing said about the visual effects yet. In this climate, Warfare should be seen by a lot of people.Simon Stanley-Camp, Visual Effects SupervisorProviding audience members with a sense of direction is the drone footage, which involved placing large bluescreen carpet down an airport runway.Without the shadow of a doubt, this was the most collaborative movie Ive ever worked on in 25 years, notes Visual Effects Supervisor Stanley-Camp. Every department was so helpful, from production design to special effects, which we worked with hand-in-hand. There were probably three different layers or levels of smoke. Theres smoke, dust and debris when the grenade goes off [in the room]. All of those special effects elements were captured mostly in-camera. Weve occasionally added a little bit of smoke within the masonry. The big IED [Improvised Explosive Device] explosion was smoky, but over the course of the 50 shots where theyre scrambling around in the smoke, we added 30% more smoke. It starts thick and soupy. You could have two guys standing next to each other and they wouldnt know it. There was this idea of layering more smoke to hide the surrounding action. We had lots of rotoscoping and layering in there.Practical explosions were used as the base, then expanded upon digitally.The Show of Force [where U.S. fighter jets fly overhead] occurs quickly. You cut back inside to be with the soldiers in the house. You dont linger outside and see the dust settling, blowing away and clearing. The first Show of Force we sped up to almost double the speed it was filmed. Its the one time we used the crane. On the whole, the action is always with the soldiers. Its handheld. Its Steadicam. You are a soldier.Simon Stanley-Camp, Visual Effects SupervisorPrincipal photography took place outdoors. Its funny because Bovingdon Airfield is a studio with five or six soundstages, but we didnt use any of them other than for some effects elements, Stanley-Camp reveals. We were shooting in the car park next to the airfield. There was one building, which is the old control tower from the Second World War, that we repurposed for a market area. Just before I was involved, there was talk about building one house. Then, it went up to four and finally to eight houses that were flattage and worked from specific angles. If you go slightly off center, you can see the sides of the set or down the gaps between the set. We had two 20-foot by 120-foot bluescreens and another two on Manitous that could be floated around and walked in.Greenscreen assisted with digital set extensions.Ramadi, Iraq is a real place, so maps and Google Docs were referenced for the layout of the streets. We lifted buildings from that reference, and Ray would say, No. That road wasnt there. We put in water towers off in the distance, which Ray remembered being there and where they were then. Palm trees and bushes were dressed into the set, which was LiDAR scanned and photomontaged before and after the battle. There is quite a lot of greens, and I shot ferns as elements blowing around with the smoke, and being blown with air movers as 2D elements to pepper back in along with laundry, Stanley-Camp states. I mention laundry because we were looking for things to add movement that didnt look out of place. There are air conditioning units and fans moving. We had some CG palm trees with three levels of pre-programmed motion to dial in, like high, medium and low, for ambient movement, but nothing too drastic. Then on the flybys of the Show of Force, we ran another simulation on that to create the air resistance of the planes flying through.When the main IED goes off, we shot that with the cast, and it plays out as they come through the gate. Its predominately compressed air, some pyrotechnics, cork, dust and debris, safe stuff that you could fire and light. There are a lot of lighting effects built into that explosion. When the smoke goes off, flashbulbs go off, which provide the necessary brightness and impact. Then, we shot it for real with seven cameras and three buried. We did it twice. The whole crew was there watching it. It was like a big party when they set that off.Simon Stanley-Camp, Visual Effects SupervisorThe fighter jet in the Show of Force sequences was entirely CG.Over a period of 95 minutes, the action unfolds in real-time. One of the first questions I asked Alex was, What is the sky? You imagine that its blue the whole time, Stanley-Camp remarks. [Even though shooting took place during the British summer], were sitting in their winter, so the soldiers are always in full fatigues, and the insurgents are running around with jumpers, coats and sweatshirts. We got a couple of magical days of beautiful skies with lots of texture and clouds. It looked great, and Alex said, This is the look. Anytime there was a spare camera and it was a good sky, we shot it. We didnt have to do so many replacements, probably about five. We had a couple of sunny days where we had to bring in shadow casters for consistency so the sun wasnt going in and out. What did require extensive work were the masonry, bullet hits and explosions. There were a ton of special effects work there. A lot of what we were doing was a heal and reveal painting them out and letting them pop back in, then moving them because with all of the wind, the practical ones are never going to go off in the right place. Maybe because they were too close or too far away. We would reposition and augment them with our own version of CG bullet holes and hits.The dust simulations featured in the Show of Force sequences were created using Houdini.Numerous explosions were captured in-camera. When the main IED goes off, we shot that with the cast, and it plays out as they come through the gate, Stanley-Camp remarks. Its predominately compressed air, some pyrotechnics, cork, dust and debris, safe stuff that you could fire and light. There are a lot of lighting effects built into that explosion. When the smoke goes off, flashbulbs go off, which provide the necessary brightness and impact. Then, we shot it for real with seven cameras and three buried. We did it twice. The whole crew was there watching it. It was like a big party when they set that off. We filled that up with a set extension for the top shot, and as the phosphorous started to die out and fall away, we took over with CG bright phosphorous that lands and rolls around. Then, additional smoke to carry it onto camera. The special effects guys had a spare explosion ready to go, so I shot that as well for an element we didnt use in the end, other than for reference on how combustible it was, how much dust and billowing smoke it let off.Muzzle flashes were specific to the rifles, rather than relying on a generic one.Assisting the platoon are screeching U.S. fighter jets that stir up massive amounts of dust as they fly overhead. The Show of Force happens three times, Stanley-Camp notes. Thats purely effects-generated. Its a Houdini simulation. We had a little bit of help from fans blowing trees and laundry on set. Any ambient real stuff I could get to move, I did. Readability was important. The Show of Force occurs quickly. You cut back inside to be with the soldiers in the house. You dont linger outside and see the dust settling, blowing away and clearing. The first Show of Force we sped up to almost double the speed it was filmed. Its the one time we used the crane. On the whole, the action is always with the soldiers. Its handheld. Its Steadicam. You are a soldier.When theyre being dragged up the drive into the house, the legs are meant to be broken in weird and awkward angles. We did a lot with repositioning angles. If you look at the before and after, you go, Oh, my god, theyre at horrible angles. However, if you look at it straight on and are not comparing it against a normal leg, its less noticeable. We did quite a lot of bending, warping and breaking of legs!Simon Stanley-Camp, Visual Effects SupervisorAn effort was made to always have practical elements in-camera.The fighter jet was entirely CG. You could get in it, Stanley-Camp reveals. Its a full textured build. The canopy is reflecting anything that would be in shot from the HDRI. What was real were the Bradley Fighting Vehicles. We had two Bradleys and two drivers. The Bradleys were redressed with armor plating fitted on the sides to make them bulkier than when they came to us raw. The gun turret was modified and the barrel added. It didnt fire, so thats all us. The major misconception of the Bradleys is that it fires a big pyrotechnic shell. But the shell doesnt explode on contact. It punches holes through things. When it fires, what we see coming out the end is dust, debris, a little puff and a tiny bit of gunk. Ive seen bigger tanks where the whole tank shakes when they fire. There is none of that. The Bradleys are quick and nimble reconnaissance vehicles.Unfolding in real-time, Warfare was shot over a period of 28 days at Bovingdon Airfield in Hertfordshire, U.K.Muzzle flashes are plentiful. We had about six different types of rifles, so we broke those down and shot extensively, Stanley-Camp states. We did a days effects shoot against black that included every rifle shot from every angle. More interesting from a technical perspective, we looked at different frame rates to shoot any of the live-action gun work to capture as much of the muzzle flashes as possible. Alex said he had to replace a lot of them during Civil War because they had all sorts of rolling shutter problems. We experimented with different frame rates and ended up shooting at 30 frames per second to capture the most of the muzzle flash, and that gave us the least rolling shutter effect. Muzzle flashes are a bright light source. Once the grenade has gone off and the rooms are filled with smoke, the muzzle flash illuminates in a different way; it lights the room and smoke. How much atmospherics were in the room depended on how bright the muzzle flash registered.The flattage sets were sturdy enough to allow shooting to take place on the rooftops.Not as much digital augmentation was required for wounds than initially thought. The house is probably three feet off the ground, and we were also able to dig some holes, Stanley-Camp reveals. There were trapdoors in the floor with leg-sized holes that you could slip your knee into, refit the tiles around the leg, and then [use] the prosthetic leg. Usually, from the knee down was replaced. Because of open wounds, arterial veins are exposed, I thought there should be a bit of pumping blood, so we put a little blood movement on the legs and shins. Otherwise, not too much. It stood up. When theyre being dragged up the drive into the house, the legs are meant to be broken in weird and awkward angles. We did a lot with repositioning angles. If you look at the before and after, you go, Oh, my god, theyre at horrible angles. However, if you look at it straight on and are not comparing it against a normal leg, its less noticeable. We did quite a lot of bending, warping and breaking of legs!The Bradley Fighting Vehicles were practical, then digitally enhanced.Drone footage provides audience members with a sense of direction. Initially, the map was barely going to be seen, Stanley-Camp remarks. It was a live play on set, on monitor, and that was it. I did those upfront, played them on the day, and the performance works. Those have stayed in. But the exposition grew, and we did another seven or eight map iterations telling the story where the soldiers and tanks are. One of those shots is four minutes long. I was going to do it as CG or motion capture, and Alex was like, I hate motion capture. Even with these tiny ants moving around, youll know. I looked for studios high enough to get wide enough. 60 feet is about as high as I could get. Then I said, Why dont we shoot it from a drone? This was toward the end of post. We went back to Bovingdon Airfield for two days and had brilliant weather. We shot that on the runway because of the size of the place. It was biggest carpet of bluescreen you can imagine. I had soldiers and insurgents walking the full length of that. Then I took those bluescreen elements and inserted them into the maps.Requiring extensive CG work were the masonry, bullet hits and explosions.The IED device explosion consisted of compressed air, pyrotechnics, cork, dust and debris, which was then heightened digitally to make it feel more lethal.Skies were altered to get the desired mood for shots.Cinesite served as the sole vendor on Warfare and was responsible for approximately 200 visual effects shots.The Show of Force shots were always going to be challenging. There is a lot of reference online, and everybody thinks they know what it should look like, Stanley-Camp remarks. Those shots work in context. Im pleased with them. Warfare has been praised for its realistic portrayal of soldiers in action. Im delighted and disappointed because no one knows there are visual effects, and there has been nothing said about the visual effects yet. In this climate, Warfare should be seen by a lot of people. It takes a snapshot of a moment. Like Ray has been saying, This is one of the thousand of operations that happen on a weekly basis that went wrong.