Imagine a story being told of a packed train carriage, having being accidentally untied from the engine, hurtling down a rail track into the unknown. Each passenger is having their own private nightmare of what might ultimately happen to them. At the end of the line. All set in the one carriage. A story in a box. A runaway train. An Extraordinary Event.
The true story is just as enthralling. Read on: On February 19, 2019, a train in the Czech Republic’s highlands flashed a brake warning light. The driver got out to try and fix the issue. Suddenly, the train began to move. Due to a slight downhill gradient and the faulty brakes, the train was suddenly rolling its way back through the highlands — with no driver at the helm and all the passengers still inside.
Jiří Havelka’s film Extraordinary Event, is set almost entirely on that single train carriage, and an ingenious use of LED exterior scenery is used, created with the very best virtual production tech. The team approached local virtual production expert Vojtěch Horký to build a Mandalorian-style LED virtual production (VP) wall that would help recreate the film’s exteriors. By production’s wrap, the technology was used on almost 90% of the finished feature, making it one of the first movies of its kind in Europe.
The prospect of attempting to film this production in a real train carriage, outside in the elements, was fraught with problems. The crew would have needed to go back every time a shot was complete, to keep the background consistent for the next take. That would triple the length of the production schedule, already set at 13 shooting days. There were far too many reflections bouncing around the carriage for the use green screen. The green screen result would just not look real.
However, in preproduction, the many different stage setups was redesigned featuring Unreal Engine and Ncam camera tracking, enabling the team to track in any environment, on any camera, with any lens or rig. They flanked the set with projection screens, an 18 x 3.5 metre Kvant LED side walls, and an 18 x 1.5 metre front wall. They even added LEDs built on top of the carriage, to simulate the sun without any additional equipment. Daylight spilled in from the projections alone. Pre-shot 8k video plates were stitched into 360-degree spherical panoramas, before being projected onto the LEDs in real time throughout production. Combined with Ncam tracking, this meant the team could visualise live CGI environments, set extensions and CGI elements directly in-camera.
Using Ncam’s Mk2 camera bar, and markers on the train’s ceiling, Horký and the talented local More.is.More crew could reposition the camera with little worry about inaccurate angles. Coming from the related field of stage direction, Jiří Havelka aimed to capture the film in chronological order, which meant changing camera positioning after almost every shot.
In fact, there were several advanced camera rigs on set. The crew could move from a dolly on rails, tripod, and crane kit. At one point a camera that weighed 18kgs! But throughout it all, the team could shoot confidently knowing that the tracking was robust. “The workflow allowed us to save a lot of time in post,” Horký explained. “Not only did we avoid the risk of green spill, we also had in-built natural lighting and photoreal scenery that the crew could control at the click of a button.”
“Jiří Havelka could also see and control the outdoor scenery for every shot directly on set. He could change the lighting and complete colour grading live, too, getting as close as possible to a finished result without waiting for post. Extraordinary Event may have been one of the first movies of its kind,” said Horký, “but thanks to the spectacular results we saw using VP technologies, it won’t be the last.”
—
Related links:
VFXR.
VFX SCIENCE 