Here’s how the performance capture tank was built.
Two 500 horsepower 480 volt electric motors spinning 25 feet long 6-inch diameter solid-steel shafts running two 5-foot diameter brass propellers at 800 RPM.
That’s just part of the engineering and technoloy orchestrated by special effects supervisor JD Schwalm and his crew at Innovation Workshop on Avatar: The Way of Water’s current machine, which allows for water flow to reach 20 to 30 knots.
In addition, a wave generating system built by Schwalm and team for the production consisted of two 19,000 pound steel ‘wave making’ wedges motivated by an 800 horsepower 400 gallon per minute electric hydraulic system.
This feat of water engineering was realized in a custom built above ground 120x60x30 foot tank holding more than 250,000 gallons of water in a studio space at Manhattan Beach Studios, where on-water and underwater performance capture for the James Cameron’s Avatar sequels took place.
The water effects generated were essentially for reference, since Wētā FX would ultimately realize a majority of the water digitally. Still, Cameron wanted the ‘performance capture’ water–waves and currents–to be as accurate as possible, necessitating a major practical effects effort.
You can see more of the tank in operation in the video above, as well as in the latest issue of befores & afters magazine, where Schwalm dives in in detail into the wave pool and current machine.