Building a Realistic Digital Universe [The Graphic Masters Series]

9 March 2016

Case Study

Alfonso Cuarón’s Gravity wowed audiences and bagged awards by the armful. And as we discover here, most of it was created digitally...

Building a Realistic Digital Universe [The Graphic Masters Series] (Desktop)

The definition of cinematography is changing. Digital lighting, composition and camerawork are at the centre of big budget projects, Oscar winning films and 3D masterpieces. Want proof? Look no further than Gravity, the big budget, Oscar winning 3D masterpiece created by director Alfonso Cuarón, cinematographer Emmanuel Lubezki and Tim Webber’s VFX team at Framestore.

Aside from one Earth scene shot on 65mm film, Gravity was shot digitally, mostly on Arri Alexa Classics. And in the majority of space scenes – such as the 17-minute continuous take showing the Earth below with three astronauts floating, then hurtling, around a space station – the only ‘real’ elements are the actors’ faces.

That doesn’t mean the cinematographer wasn’t present on set, lighting and shooting live action. What it means is that Emmanuel ‘Chivo’ Lubezki was also involved in every stage of creating the images that make up the film – both those shot on set and those generated digitally.

“I had to learn some new tools that are part of what cinematography is becoming.” Lubezki told American Cinematographer.

“We wanted to surrender to the environment of space, but we couldn’t go there so the only way of doing it was through all of these technologies.” Emmanuel Lubezki

How to make a film set in zero gravity look believable? Cuarón and Lubezki chose long, immersive takes mapped out early in production and kept these shots elastic – starting wide, coming close, then wide again. Gravity used a fraction of the cuts an average movie uses – hundreds rather than thousands – to make it feel more real, immediate and intimate. Lubezki has likened it to watching the action in real time.

A five year mission

The five year project began with physical puppets used to block out the actors’ positions in zero gravity. These formed the basis of black and white block animation of the whole movie produced by Framestore. Layers and layers of colour, volume and light were then added. But with humans and cameras spinning at different rates, the blocking and camera choreography also had to be worked and reworked until it fit together spatially.

Scenes were regularly scrapped and begun again from scratch to respect the physics of space.

Lighting was key. In Gravity’s case, this required Framestore, under Lubezki’s close supervision, to design prelight for the entire film. So a precise map around Earth was plotted to pinpoint lighting and colour references.

Lighting was also crucial in blending the actors’ faces with virtual environments later in the process. This called for using naturalistic light on the faces and later matching the CG animation lighting as closely as possible.

In Lubezki’s “light box” the CG environment played against the walls to light the actors’ faces and provide visual cues. For instance, Framestore’s raging CG space

station fire was played to ensure the match of tone, colour and rhythm with Sandra Bullock’s face as her character tries to escape.

On set in zero gravity

Framestore built more than 2,200 models for Gravity – a number more like a CG animated film than a visual effects-heavy title.

From incredibly detailed interiors for the International Space Station to props for the space shuttles, most of the models were later ‘destroyed’ too.

The biggest asset build, the ISS, was a 100-million-polygon model, made possible by rendering in Arnold, which is fast at raytracing polygons. In collaboration with Cuarón, Framestore built everything that physical set builders would create and fine-tune.

Sandra Bullock filming 'Gravity'

Sandra Bullock brought a human warmth to the cold depths of space

Gravity in numbers

  • 2,217 unique CG models were built for the film
  • Total lines of Arnold Renderer shader code: 71,178
  • Framestore coordinators took over 2,100,000 words of notes during production – that’s four copies of War and Peace
  • To render the whole show on a single-processor laptop, Framestore would have needed to start around the dawn of Egyptian civilization
  • Total number of computer generated stars in our star field: 30,741,312
  • Thirteen shots are longer than one minute in length – in total they make up 68% of the movie
  • Around 80% of the film is computer generated

Read more in the Graphic Master Series.