3D Artist
Aug
6

Prometheus environments – MPC’s Julien Bolbach interview

News & Features
by
stephen.holmes

In the first of three Prometheus interviews this week, 3D Artist talks exclusively with MPC environment lead Julien Bolbach about creating the world of LV-223.

Prometheus environments - MPC's Julien Bolbach interview

No matter what opinion viewers of Prometheus have come away with, most agree that the visual effects are some of the greatest yet seen in cinema. How did you achieve such high quality in the visual effects?

Thanks for that! It’s always difficult to judge your own work, but I think it’s a combination of really hard work, passionate people, and no compromise in terms of delivering quality.

Then there’s motivation. Working on a sci-fi movie with Ridley Scott is not something that happens every day, and that added special meaning to what we were doing. Although, it added a lot of pressure too!

It‘s also a team effort across MPC. There was a great deal of communication between the leads and the supervisors to make sure that the workflow and the elements provided were suitable for everyone, with the goal always being to keep quality and consistency throughout the shots.

In terms of organisation within the department, there were always two leads working on the show in parallel (myself and Eddy Richard in the first few months of planning and production and myself and Marco Rolandi, during the last six months of the project). We also got significant help from our Head Of Department as the show began to grow. Given the size, the complexity of the project and the nature of the work, we ended up splitting the show into sequences among ourselves. Marco focused mainly on the space shots and the landing sequence, while I was handling most of the planet and pyramid shots.

We’ve seen computer generated space environments in a lot of sci-fi films. How did you go about making space feel unique for Prometheus?

The main reason why the space environments feel unique is that we tailored our work to match Ridley’s vision, which was unique in the first place. It was all about the relationship between the Prometheus and its surrounding environment; the Prometheus should appear as a fragile little toy around this moody, stormy and uninviting background. We tried not to watch other sci-fi movies as a reference point to ensure we were sticking to Ridley’s unique interpretation for the movie.

What kind of references did you use when creating the space and planet environments?

For the space shots Ridley came with references from Saturn and one of its moons. He also spoke to NASA scientists to get an understanding of its environment and climates.

We carried out extensive research of pictures of earth from space; Jupiter and Saturn’s surface and rings; clouds and storm photos. We also explored more exotic paths, looking for coloured fluids, waves, skin and blood vessel patterns. The main concept behind the space shots is that the LV system is in turmoil – dynamic and changing, almost like a living organism. In the end we looked at anything that helped convey that feeling.

For all of the shots of the LV223 planet when they are landing and afterward, the main references were Wadi Rum in Jordan for the huge mountains, and Iceland for the volcanic ground and cloud formations.

For the pyramids we were given concept art from Steve Messing, but the previs process slightly changed the shape of them. We started from the ultra low-resolution pyramid we got from the previs and did some additional concept work at MPC with all of the references we were given from Jordan.

Prometheus environments - MPC's Julien Bolbach interview

What was the process behind creating the planet environments?

We followed two different approaches according to the nature of the sequences we were handling. The space shots and the landing sequence comprise of a few key-establishing shots of environments that are only seen in that specific part of the movie, while the core of the action and the majority of shots are set on the landing strip that goes from the Prometheus to the main pyramid. We therefore decided to address the first part of the work on a shot by shot basis using traditional 3d digital matte painting, while focusing on building a real CG environment for the main LV223 shots.

While being traditional in nature, the work on the landing sequence was challenging due to several different factors: lack of real-life counterparts of what we were trying to achieve, stereo requirements, changing lighting conditions and existing plate integrations. A typical space shot required the painting of LV223 in different layers in order for them to be animated, with each layer being provided in at least two different lighting conditions in order to simulate moving shadows and other lighting effects.

When thinking about the surface LV223 environment, the plan was to use the original plates shot in Iceland, add the CG pyramids, enhance the ground with more pinnacles (they had a few on set) in a 2.5d process, and add the Wadi Rum mountains to the background. At that time, we had no idea of the exact shots that would be done.

Before the principal photography, the supervisors went to Jordan to shoot as much as they could from Wadi Rum, from helicopter shoots to 360 degree panoramas with different lighting conditions. We spent some time using Photoshop to align the stitches, and we got almost a pixel-to-pixel match on 64K stitches. Then, the footage helped us to recreate a 3d model of the mountains, and the panoramas to spherically project on the model.

When they shot the action in Iceland they dressed the flat land with pinnacles and added rock, which gave a more interesting look to the plates. However it became evident quite quickly that we had to change our initial plan, knowing the amount of shots, the type of shots, and the different lighting conditions required. We therefore started building a full CG ground, based on lidars of two locations in Iceland, that we enhanced in Mudbox. We had pinnacles from Iceland modelled and textured from MPC’s assets department, and we modelled and textured a huge variety of rocks to complement them. I wrote a script in Maya to populate the ground with pinnacles, using density and scale maps, and then placed rocks with dependencies (big rocks would go around pinnacles, smaller rocks around big rocks, etc.), to get a realistic feel to the scattering.

We also created different sets of seamless high res textures using Iceland as a reference: different types of sand, small gravel, flat rocks. Using both photos from the Iceland shooting, the distribution maps and straight painting, we created masks to overlay these sets and a base terrain that looked convincing within the spectrum of distances we had to cover (which was quite wide: it went from 3 meters to 300).

This still wasn’t enough, however, as in reality mounds of sands surround underlying and surface rocks, and their overall shape is determined by the wind as well. We assumed the direction of the wind to be parallel to the tempest we see in one of the sequences, as if the valley was some sort of wind tunnel, and we coupled this information with the distribution map in order to have sand in the protected side of the pinnacles. The final result was a new set of maps to drive sand and tweak the displacement of the ground. We went through a few iterations before the general layout was approved, then we spent a bit of time optimizing the geometries and render times. The ground was our biggest asset, with around 25 million polygons and displacement everywhere, which needed a huge amount of render time (up to 8 hours per frame for the most complex shots).

The Pyramid and its surrounding walls were a pretty straightforward asset to build, although we started with the textures in order to match the existing Wadi Rum reference, and then refining the model, following the textures, and adding displacement in ZBrush.

Given the huge amount of shots in the same environment, we had to setup a sustainable workflow for the 10+ artists working on LV223. We put all of these elements (ground, pyramids, mountains) together in a master scene, which was then customizable by the artists themselves using their own light rigs and tweaks. We used another tool we wrote in the environmen department to easily launch renders for a collection of similar shots, just by swapping the camera at render time. In this way we could have one artist handling a full sequence of similar shots efficiently.

How did you make the environments feel alien/extraterrestrial?

I think that the locations selected by Ridley  helped a great deal to give this alien feel. Iceland in particular was a huge source of inspiration, as it looks so far from what we are used to.

For the space shots our team at MPC were always trying to remove all of the elements that looked too ‘earthy’, by adding extra elements such as electric arcs, or by using the clouds with the strangest and most intriguing shapes.

For the pyramids, the brief was to make it feel like it could have been an alien creation, but also that it should have a natural formation. As such it appears intriguing and rich, but confusing for the audience as well!

What part of your work on Prometheus are you most proud of?

I remember the day after we completed a few months of work on the show when we put all of the elements together for the planet environment: the big Wadi Rum mountains in the background; a first version of the ground with all the pinnacles and rocks; the pyramids; the walls; and completed a first quick comp with a sky line and a bit of atmospherics. It began to look like the environment that Ridley had been talking about for months, and it was then that we knew that we had taken the right decisions in the process of making it a reality.

You can read more about Prometheus in issue 45’s Studio Access, out next week, August 15. You can buy it at imagineshop.co.uk or get a digital version at greatdigitalmags.com

Prometheus environments - MPC's Julien Bolbach interview

  • Audrius

    Brilliant work by Julien and other folks at MPC..

  • Fabian

    GG Juju ! Impressive achievement