'1917' VFX artists had to fully reconsider how films are made

There is a moment in 1917 – the blockbuster from the First World War that hit the cinemas on Friday – where a plane crashes from the sky. Normally, when producing such a scene, the director would have a very important tool in their arsenal to convince the public that what they see is real: the ability to cut into other images.

Wired UK

This story originally appeared on WIRED UK.

As the plane approached the ground, they could cut away to the faces of shocked bystanders, cut back to show the flaming wreck, and so on and so forth. By doing this, viewers’ brains never have time to really take a closer look at the scene, because it only takes them a few seconds at a time.

But in 1917 the camera never cuts away from the action. The film – directed by Sam Mendes and inspired by his grandfather’s memories of the war – is presented as a single, hectic recording. It tells the story of two soldiers charged with conveying a crucial message and follows them everywhere – across minefields and through trenches, with the chaos of war all around them.

The visual effects team had to maintain the illusion for two hours, which meant that the way films were made had to be fully reconsidered. “The one-shot thing has been done before,” says Guillaume Rocheron, an Academy Award-winning visual effects artist at studio MPC and VFX supervisor on 1917. “But it’s always done in environments that have been closed.”

In a movie such as Birdman from 2014, for example – the most recent high-profile example of a “one-shot” movie, cuts are made when the protagonist is obscured by a wall or walks around a corner. In 1917, where most of the action takes place in open spaces, there were far fewer opportunities to implement this type of austerity – which meant greater dependence on complicated digital austerity.

“From the outset of production, we have looked at how we could make it look continuous and therefore absolutely imperceptible in terms of appearance and in terms of how the camera flows,” says Rocheron, who, together with Mendes and cinematographer Roger Deakins worked on the film. “Every transition looks a bit like a magic trick.”

There were numerous different approaches depending on the type of recording. For the plane crash, the team created a digital plane that crashed into a digital shed, which was then mixed with a physical replica of the plane that was shot on location. “It requires incredibly advanced rendering and animation and blending to go from take-to-take,” says Rocheron. “One scene could be recorded at Shepperton Studios and the next one at Glasgow and you have to make it blend seamlessly in one way or another.”

The task was made more difficult because the film was produced in native Imax – a widescreen format with an incredibly high resolution, which meant that the digital paintwork of the VFX artists had to be even more precise and complicated. But the biggest complicating factor was the way the film was shot.

With a normal movie, recordings generally range from a few seconds to about 20 seconds. “Oners” – recordings of 60 seconds or more – are remarkably rare. In 1917, some shots ran for a few minutes. “At VFX it’s all about fooling the public, through the quality of computer graphics, the movement and the perception of reality,” says Rocheron. “As soon as you have a cut, your brain is reset – but in our case you can really study everything. Your brain has time to look at things and analyze them, especially in Imax format. “

That also posed a technical challenge. In general, VFX artists work during the day and then run the hardware-intensive display of the high-resolution images at night so that it is ready to be viewed in the morning. But it takes all night to make a 10-second recording, so if you make one that lasts a few minutes, it would take days.