Mortal Engines used holograph set design

Production took place almost entirely at Stone Street Studios in Wellington, with Peter Jackson involved as a co-writer and producer.

Some of the sets were so complex that the team first modelled the city environments using 3D Augmented Reality (AR) by way of a programme called HoloLens Holographic.

Sets were initially designed using AR before being placed onto Stone Street’s stages virtually so that the team could see how they would physically fit in the space ahead of the actual builds.

“Augmented Reality is fantastic when it comes to visualising totally impossible structures,” says Ra Vincent, the film’s conceptual art director.

“The headsets gave artists an opportunity to experience their drawings and sets at full scale. Not everyone can navigate a 3D model, but everyone can wear glasses and navigate a hologram.”

Rivers’ main unit used all four stages at Stone Street, building more than 70 sets for a principal photography schedule that stretched to 86 days. All the sets comprised at least partial physical builds, though many were digitally extended in post-production.

Stone Street Studios was originally set up by Peter Jackson and his team 20 years ago as a base for the Lord of the Rings trilogy and the filmmaker has shot all of his fiction features at the studio.

Sets for Mortal Engines were frequently mounted on gimbals and motion bases so that the movement of the mobile cities of the story could be simulated in-camera.

There was also a limited schedule of location filming.

“We did actually shoot a handful of locations in Wellington – a small local swamp and some coastline settings,” says Jared Connon, the film’s production manager, in comments to KFTV.

“It was great being able to pop out of the stages and have these fantastic and easily-accessible locations right on our backdoor step. We didn’t build any sets outside the studios.”

New Zealand remains a southern hemisphere production hub. The country offers filming incentive support through the New Zealand Screen Production Grant, comprising a base 20% cash grant.

Nearly 30 international shoots were awarded incentive support in the 2017-18 year, according to figures from the New Zealand Film Commission, with combined spending reaching just under NZ$694m.

See KFTV's production guide for more on filming in New Zealand.