Director Taika Waititi reveals the filmmaking secrets that made the movie’s most stunning sequence.

When it comes to creating stunning visuals, director Taika Waititi has a few tricks up his sleeve. Lucky for us, he’s happy to share his secrets. We learned a lot from Waititi’s Thor: Ragnarok commentary, but one of the track’s most interesting moments comes when the director divulges about the how the movie uses some groundbreaking visual techniques that he says have “never been done in film before.”

In an epic flashback sequence, Tessa Thompson’s Valkyrie and her army of pegasus-riding warriors soar through the air to face off against Cate Blanchett’s evil Hela. The slow-motion scene utilizes cutting-edge lighting effects to capture the grandeur and movement of the battle, as well as the shadowy anguish of Valkyrie’s defeat. The lights are at once entrancing and disorienting, graceful and jarring. But perhaps even more fascinating than the sequence itself are the technical processes that brought it to life.

To create the sequence’s surreal look, Waititi and visual effects supervisor Jake Morrison collaborated with Satellite Lab, a creative studio founded by Carlo Van de Roer and Stuart Rutherford. Satellite Lab’s patented DynamicLight technology uses special rigging to move light sources at incredible speeds (try eight times the speed of sound). This allowed the Thor: Ragnarok effects team to simultaneously capture the flashback’s slow-motion action and rapidly moving light. In an interview with The Verge, Waititi details the mechanics behind the visuals:

It was about a hundred strobe lights, strung together, and they all fire off within about a second of each other, all in sequence. You shoot a subject with a Phantom camera, which is shooting at 1200 frames per second… The cameras stay still, but the light is traveling around, and the shoot has these big long shadows everywhere. So you get this light wrapping around your subject in a way that’s very surreal and dreamlike, and doesn’t exist anywhere else.

Here’s Waititi playing with the effect himself in an early development test: 

Though the sequence lasts a minute and a half, the shooting process lasts only a few seconds. The footage is later slowed and elongated to capture about one frame per flash, creating the slow-motion effect we see. In an interview with Syfy Wire, Morrison acknowledges that this filming method poses a sizable challenge for the actors because “you’re basically trying to squeeze in these incredible acting beats and performance moments into literally less than half a second.” Naturally, Thompson and Blanchett kill it, packing emotional wallops into each frame.

Using DynamicLight can be demanding for technicians and actors alike. But, in the case of Thor: Ragnarok, it results in a seamless, stunning, and visually singular sequence that audiences won’t soon forget. Check it out for yourself and listen to Waititi’s commentary in the clip below:

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