The bulk of the vfx work was to provide a lot of CG vehicles because it's very expensive to replicate on set, and the Army would not release current vehicles. Above is Camp Matilda. 

TB: Was there a lot of pre-pro for the vfx? Did you create any previs or animatics that would help keep the show on budget?

Stephane Paris: We used previsualisation and animatics for key shots, including the Superhighway and convoy sequences. It was important to plan the vehicles' speed, positioning and configuration in advance, getting "sign-off" from both the director and military adviser before setting the shot in high resolution.

DS: In 2D, some early tests were created for the various scopes, starting with standard issue binoculars through to night vision scopes, rifle scopes, range finders and sniper scopes. We also did some range finders.

TB: What was the bulk of work you had to provide for the show?

Partridge: Basically we had to provide a lot of CG vehicles because it's very expensive to replicate on set, plus they are all current vehicles and the U.S. Army can't release those. We had to create all of those in CG -- LAVs (Light Armored Vehicles), tanks, two types of helicopters and a jet plane. We also had to recreate several Iraqi cities that feature in the story as the American army progresses through Iraq. They were created as matte paintings and enhanced with 2D elements of smoke and fire.

TB: Did the documentary style of shooting cause a lot of vfx challenges?

Partridge: It was certainly one of the challenges. For some of the shots, we put the camera shake in afterwards so then we shot locked off. Other stuff was handheld so we had an allocated tracking department to track any shots that needed it. We'd then use motion blur and all the relevant tricks to make it fit in with the others.

TB: Did the visual effects for Generation Kill balloon as the post-production process started?

Partridge: As with any show there are the shots you bid on and then the stuff that appears throughout the show. There was a lot of clean up as they did have fake, imitation vehicles, especially on the LAVs where they used an existing light armor vehicle and tried to dress it up to look like the specific one used. Unfortunately, that didn't work so we had to do those fully CG in the end. We also had to clean up the ones they used in camera and that added extra work. Instead of having a clean plate we'd have to clean out the in camera things they used too.

TB: What are your favorite sequences?

Partridge: There were probably two different aspects to that… there were some very heavy CG shots in the super highway sequence. It was absolutely fantastic. They looked completely and utterly realistic as a six-lane highway completely log-jammed with CG U.S. Army vehicles. There was a lot of 2D stuff in there and initially might not look spectacular but it had a fond place in my heart because it involves an awful lot of 2D layering of smoke, explosion and flames. There is one sequence which is a night time bombing of a town called Ash Shatrah. We ended up not using any of the elements provided apart of some bluescreen footage of some Marines and then we completely created a night time bombing using just those elements and stills.

DS: There is a sequence where the convoy is approaching the Iraqi border at night. The audience sees the action from the POV of the soldiers wearing night vision goggles (NVGs). Ahead of them are fires, artillery strikes, anti-aircraft tracer fire, attack helicopters and billowing smoke. The original footage was of an empty day-lit desert; the finished sequence gives a claustrophobic and action-packed impression of the soldiers' point of view of operating in the midst of battle.