There is a moment in 1917—The box office success of World War I that hit theaters on Friday — where a plane crashes from the sky. Normally, when producing such a scene, the director would have a very important tool in his arsenal to convince the audience that what they are seeing is real: the ability to cut other images.
This story originally appeared on WIRED UK.
As the plane approached the ground, they could cut the faces of shocked spectators, trimming to show the remains in flames, and so on. When doing this, the brains of the spectators never have time to really examine the scene, because it is only in front of them for a few seconds at a time.
But in 1917, the camera never moves away from the action. The film, directed by Sam Mendes and inspired by the memories of his grandfather's war, is presented as a unique and frantic shot. It tells the story of two soldiers in charge of delivering a crucial message and follows them everywhere, over minefields and trenches, with the chaos of war around them.
The visual effects team had to maintain the illusion for two hours, which meant totally rethinking the way the movies are made. "The one-time thing has been done before," says Guillaume Rocheron, a visual effects artist awarded an Academy Award in the MPC studio and visual effects supervisor at 1917. "But it has always been done in environments that have closed."
In a movie like 2014 Bird man For example, the most recent high-profile example of a "one-shot" movie, cuts are made when the protagonist is hidden by a wall or walks through a corner. In 1917, where most of the action takes place in open spaces, there were many fewer opportunities to make these types of cuts, which meant a greater dependence on complicated digital clippings.
"From the beginning of production, we saw how to do it so that it looks continuous and that it is absolutely imperceptible in terms of appearance and how the camera flows," says Rocheron, who worked alongside Mendes and cinematographer Roger Deakins in the movie. "Every transition is a bit like a magic trick."
Countless different approaches were used depending on the type of shot. For the plane crash, the team created a digital plane that crashed into a digital barn, which was then mixed with a physical replica of the plane shot at the scene. "It requires incredibly sophisticated rendering and animation and mixing to go from shot to shot," says Rocheron. "You could film a scene at Shepperton Studios and the next scene in Glasgow and somehow you have to mix it perfectly."
The task became more difficult because the film was produced in native Imax, a wide-screen, incredibly high-resolution format, which meant that the digital painting work of visual effects artists had to be even more precise and intricate. But the biggest complication factor was the way the film was filmed.
In a normal movie, the shots generally vary from a few seconds to about 20 seconds. The "Oners", shots of 60 seconds or more, are remarkably rare. In 1917, some shots lasted several minutes. "VFX is about tricking the audience, through the quality of computer graphics, movement and the perception of reality," says Rocheron. “As soon as it is cut, your brain is restored, 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 presented a technical challenge. In general, visual effects artists will work during the day and then allow intensive hardware reproduction of high-resolution images to run at night, so you are ready to check in the morning. But it takes all night to make a 10-second shot, so making one that lasts several minutes would take days.