How the Everest VFX team scaled new heights

When director Baltasar Kormákur set out to make Everest, the story of two ill-fated expeditions to he famous peak, it was always going to be a tough challenge. Production would film on location in Nepal right on the foothills of the mountain, with the Italian Alps and Iceland also serving as shooting locations. In addition, greenscreen photography and backlot shoots took place at the Cinecittà Studios in Rome and Pinewood Studios in the U.K. – from which the many rugged action pieces of Everest would be crafted. That mean that in bringing together the film’s sequences, visual effects played a key role, overseen by VFX supervisor Dadi Einarsson.

“This is essentially a true story drama that happens on the slopes of one of the most inaccessible places in the world to shoot,” Einarsson told fxguide, “so it was clear that we wouldn’t be able to shoot large portions of the script in the actual locations. It’s the most recognizable mountain region in the world, so there was a very real requirement to get it absolutely right. I felt a huge burden of responsibility to the story which so many people know and love and to the survivors of the tragedy and their families that the VFX be invisible and that the result feel real.”

Much of that realism, of course, would come from the real locations. DOP Salvatore Totino acquired footage, on ARRI Alexa XT cameras, in Nepal from Kathmandu up to the Tengboche monastery for scenes leading up to basecamp. “Once we get to basecamp, however,” notes Einarsson, “we are on the Cinecitta Studios backlot in Rome. From there on upwards we shot either there, in Val Senales in the Dolomites or on the 007 stage in Pinewood Studios. That meant that backgrounds would have to be created for a huge number of shots for everything that happens on the mountain.”

Einarsson established a clear methodology (see side-bar, right) for delivering the necessary shots, a task that would be handled primarily by his own studio RVX, which took care of all the shoot, methodology, layout, previs and data turn over including the photogrammetry model, and was then aided by Framestore, Important Looking Pirates, Union VFX, One Of Us and Milk VFX. Stereo D carried out 3D conversion services.

Principal to the methodology for achieving shots was a plan to build a scale accurate photogrammetry model of the Everest region. According to Einarsson, the model would enable the team to create previs and postvis accurately, “safe in the knowledge that all of our views would represent a composition based on reality. What I really wanted to avoid was a situation where several opinions would be offered as to whether the mountain views should be this or that. We started with reality and worked from there. This basically gave us the confidence that we could concentrate on finishing shots without the danger of having to go back to square one if someone pointed out a discrepancy down the line.”

The model also allowed visual effects artists to bake out very high resolution areas, then re-project high resolution photography as the starting point for CG environments and fully CG shots. RVX photo researcher Jon Einarsson began the process of finding as many images of Everest and the surrounding areas as possible. Many helicopter images were acquired from David Breashears, a climber and cinematographer who was also a producer on the film. “Breashears had shot Working Title’s 2008 documentary Storm Over Everest,” relates Dadi Einarsson. “During that expedition he had shot 35mm plates and tiles of the ascent which we had access to. We scanned these and used them as part of our library of elements.”

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Photogrammetry software from Designing Reality was then used by Olafur Haraldsson to supply ‘giant solves’ to RVX’s CG team, led by Matthias Bjarnason. “They would then re-model and project images,” explains Einarsson, “piece together all the different patches and fill in the gaps where needed. It was a huge job but absolutely the foundation we needed to make the whole show work as legitimate and believable scenery.”

LIDAR scans of locations and stages were also part of the surveying effort for Everest. “This was very difficult to achieve on some of the Italian mountain locations,” admits Einarsson. “The logistics of trekking through deep snow into positions to scan from would take a long time for Taylor Tulip-Close and the on set team, and then the scan itself obviously takes a while. LIDAR scans were also taken on all of our stages so that we could use them as a basis to extend with CG as well as to assist in match moving. We took an enormous amount of reference photos and HDRIs of all sets and locations.”

The photogrammetry model would prove even more invaluable after a devastating avalanche on the mountains shut down a planned summit expedition to acquire plates. “We originally planned to send cinematographer Kent Harvey to the summit to shoot plates and 2nd unit with body doubles in costumes,” says Einarsson. “I had provided a plates list which they would endeavor to do their best to cover – locations, directions, tiles, time of day etc. He and his team were in basecamp and had been shooting plates there as well as the icefalls, when the avalanche happened killing 16 Sherpas. The mountain was shut down and we had to regroup and plan. After the summit expedition was cancelled we had to figure out how to achieve the shots with what we had and the photogrammetry model carried even more weight.”

The result, suggests Einarsson, was an incredible starting point for the backgrounds. “I think the fact that we were 100 per cent sure that our backgrounds were correct in terms of what we would see if we were there gave us the confidence to push on and spend our energy on integrating everything and making it look real and beautiful. Basic stuff like making sure the lighting was correct – white levels matching was a huge one for the snow as any tiny deviation would really explode in DI.”

Of course, additional elements helped too, such as snow drift in almost every mountain shot. “This was a combination of Houdini FX sims and elements shot against black,” states Einarsson. “We added ice breath to over 200 shots in the film which we kept subtle but really helps integration and the feeling we’re in a cold place, even on a subconscious level. The ice breath was animated in Maya using fluids in order to match the breathing, dialog and wind direction/turbulence. One Of Us used Houdini and a combination of elements and DMPs for the storm hit. Important Looking Pirates used Houdini and Maya for their white out shots, once we’re in the storm as well as their in house volumetric particles renderer Tempest.”

Several final shots in the film were, using the CG built environments, completed as synthetic helicopter fly overs. “Basically these were fully CG shots animated in Maya using the layout model of the Everest region,” outlines Einarsson. “For me these were the most fun to do as we had complete freedom to find angles, staging and camera moves within the parameters of what was needed in the cut. It was a very creative and rewarding part of the process. Working with the cut, understanding what was needed from the shot in terms of the sequence and surrounding shots but also in terms of the story as a whole. I tried to stage these shots so that you would see not only the foreground action but in such a way that we see familiar landmarks in the background. For instance when Rob and Doug are walking to the summit, we see the Hillary Step, South Summit, the South Col and Lhotse Face behind them, all locations of note in the story. Constantly using these shots to subtly convey the scale of the mountain and distance between key locations and landmarks helps give the audience a familiarity of the mountain and context.”

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“Once a previs shot was approved,” adds Einarsson, “it was turned over to whichever VFX studio was doing it – RVX, Framestore or Important Looking Pirates. We would bake out high resolution geo, re-project photography through Maya cameras and use these as the base for the models and textures which would then be enhanced, matte paint projected on, shaders added and lots and lots of fx. We shot textures for all the main cast wearing their summit suits and digi-doubles were then animated to match the action and continuity of the shots around them.”

Einarsson’s goal always was for the visual effects to be nested in reality. “It’s the approach I always try to take. This is the fourth film Baltasar and I have collaborated on so we have developed a good relationship and understanding of one another’s likes and methods of working. He likes to give me freedom to express my ideas and show them to him and I know that what he wants most of all is something that progresses the story and feels like it belongs with the rest of the film.”


 

Case study – Framestore

Framestore’s London and Montreal offices combined to deliver more than 200 shots for the film, including fully CG shots, DMP work, set extensions and snow and cloud generation.

One particular CG shot included an aerial sequence over the South Summit of Everest. “We really wanted to capture the feel of helicoptering round the summit of Everest, even though this would not be possible at such heights,” said Framestore visual effects supervisor Glen Pratt, in a story on Framestore’s website. “We really pushed the stark photographic nature, the very hot highlights and punchy shadow, that you get at such altitude. The shot was an opportunity to bed the real world environment into a fully CG shot, making the audience truly feel like they are witnessing the characters’ final climb to the summit’.”

Framestore CG supervisor Rob Allman added: “This is an extremely distinctive view. Although it feels like we start to track downhill, it’s actually that we’re levelling out, finally, at the famous summit. We added the small bundle of coloured flags, left by previous climbers, to mark the exact spot. The spindrift was a permanent fixture of Everest – the light, swirling patterns of snow that’s been kicked up by the wind on the surface. It’s a real threat for climbers in such highly exposed spots, in its speed and the way that it impairs vision. It formed an ongoing task for our VFX team, creating the right spindrift volumes, renders, and simulation.”

Head back to fxguide soon for more on Framestore’s contribution to the film.

Case study – Important Looking Pirates

ILP predominantly worked on the whiteout effect when the storm hits the crew. Visual effects supervisor Stefan Andersson outlines the work.

Plate prep: The first phase was to roto out each actor separately. Since the majority of our shots were filmed in Pinewood we also needed to do some minor set extensions to complete the mountain side and add in rocks into the snow. Initially the brief was that we didn’t need to do much extensions as we should cover all the actors with the storm. But halfway through after a screening with the director it was decided that we need to see the actors more. It was too difficult for the audience to identify and see the actors. So we had to go back to the plates and do more of a DMP solution to get more detail into the background on a number of shots. A few shots were already quite DMP heavy as we needed to great the mountain side or a drop off.

All shots had a rough geometry built up so that we could generate depth information into the plate. As we were rendering everything in deepexr we set the depth of the actors with the roto and also projected the plate onto the geometry to get the depth information. Some shots were highly detailed as they were full cg shots or 70% of the plate was cg.

How much storm to show? The difficulty is the amount of smoke and detail you need to get into the whiteout and all the movement. Dadi and Baltazar also wanted it to be fierce and deadly, and we kept pushing it until we had a “formula” that worked. A lot of plates were filmed to capture the spin drift that you see on Everest. But most of those we couldn’t use due to the character of the storm. Even though a whiteout is “white”, there is a lot of different kinds of turbulence that are happening in it and a lot of depth feeling that needs to go into the snow clouds. We studied as much footage we could which was filmed inside a snow storm, but again.. due to the nature of a storm and how much a camera can capture in depth we couldn’t find a lot of material. The best material we found was filmed on the US research facility on Antarctica.

Effects creation: We needed a fast turnaround and on the effect so that we could view it and adjust it easily. And for continuity we could not rely on simulation for each shot. Our approach to this was to create various noise grids in Houdini which we had a points travel through. We ended up with about 8 different setups that we used and combined to get the main snow direction effect. These grids was also used to get velocity to smoke. The layout/direction and speed was set in Maya with a setup our TD had made. This was then sent from Maya to Houdini where we rendered out all the particles in Mantra, and all the smoke elements were rendered in Tempest (our in-house volume renderer). This was fully automated so the artists actually never needed to open up Houdini.

Even though we generated a lof of snow and smoke in CG we used quite a lot of plate elements to get that last bit of realism into the shots. The main direction and density was always cg, but elements were used to have snow bits closer to the camera and sometimes we added in the elements onto the ground to get a feel of interaction.

Case study – Union VFX

Union mostly created Everest environments between basecamp to camp 1 (and above), as well as the Pumori mountain range. This environment was used for the helicopter rescue sequence, seen both from outside the helicopter and through the windows as they fly through. Visual effects supervisor Simon Hughes describes Union’s contributions.

Mountain environments: These were created using a combination of Maya for geometry and lighting and ZBrush for sculpting; NUKE for projections and compositing and Houdini for snow simulations, and rock simulations. The high resolution textures from Everest were supplied to us from RVX along with basic geo of the mountain range, in addition to this they also supplied live action footage shot on RED and Alexa and DSLR from the helicopters as they flew from basecamp to camp 1 and above.

Making snow: The most challenging snow addition shots for us were the moments where the helicopter comes in to land at camp 1. The plates were shot at the Dolomites and had actually landing moments with tonnes of spin drift snow swirling around the helicopter obscuring the backgrounds that we needed to replace with our CG Everest. To make the shots work we had to simulate spinning snow in Houdini and get this as close as possible to the original photography so that we could blend in with the real snow seamlessly. Throughout the sequences there were many variations on the different types of snow fall, from the large scale spin drift and blizzard moments down to just subtle flurries and snow kicking up over rocks to bring life to CG environments.

Compositing challenges: There is a very fine balance that needs to be achieved where we can seamlessly blend into original photography, yet retain enough of the new environments behind the snow to tell the story, in addition to this as there was real snow in the plates, there is a lot of time spent matching the movement. To create depth we needed to meticulously rotoscope objects and character from front to back separately so that we could have haze levels adjusted independently as well as snow falling between.

Case Study – One of Us

One of Us worked on two sequences for Everest overseen by VFX supervisors Dominic Parker and Emmanuel Pichereau. This firstly involved the summit sequence, everything above Hillary Step. The live action was shot on a large greenscreen stage and due to the size of the greenscreens a great deal of prep work was necessary to make sure the shots would work. The work was a mixture of DMP, set extensions and practical and CG particles for atmosphere.

Original plate.
Original plate.
Final shot.
Final shot.

One of Us also produced the massive storm which engulfs the climbers, and which needed to be very atmospheric and dramatic. The studio used a great deal of reference material, including GoPro footage, that showed the sky at the edge of the atmosphere as very deep, vivid blue. The light and shade is pin sharp, so One of Us had to create environments adding a complex atmosphere of snow, mist, cloud and tiny ice particles to make the air perceptibly sharp and cold.

Case study – Stereo D

Stereo D handled 3D conversions for Everest, with Stereo D Chief Creative Officer and EVP Aaron Parry telling fxguide about the work:

The stereo brief: Director Baltasar Kormakur really wanted to visually bring the audience to Nepal so they could understand what draws adventurers to a place like Everest. What excited us was the opportunity to work with a director who wanted to use 3D in a drama – not traditionally a genre associated with stereo imagery – as part of his storytelling mechanism. Since extreme peril was part of the experience, ensuring that the 3D would enhance the gravity of the situation for the characters was our foremost task.

Working closely with our Stereographer Dave Phillips, Kormakur and VFX Supervisor Dadi Einarsson wanted a lot of visible detail  in the sweeping vistas and mountain ridges. It was important that we not only had depth in our foreground characters but also well into the background. ”Push the Lhotse Face,” (referring to the famous peak connected to Everest) was a favorite note to come out of our reviews sessions. This “deep background” use of the 3D emphasized the stratospheric heights of the climbers and underscored the wonder of the landscape, along with the jeopardy.

Tech challenges: We asked for and received all of the original greenscreen oneg shots long before the final vfx versions. This allowed us to not only get a head start on rotoscoping and breaking out the scene but also we able to separate the in-camera snow with vfx snow added later. We worked closely with RVX, as well as Framestore and Union in London, and Important Looking Pirates out of Norway on utilizing their compositing scripts to make cleaner and more realistic stereo.

The summit shots: What was great about this project was there were so much scenery and wide angled shots to work with throughout the film. One scene where the 3D really emphasizes the vastness and the viewer can experience the most out of the scenery would be when the teams are reaching the summit. There are several 360 views and breathtaking vistas that are unique to this movie.  We have an increased amount of stereo and really detailed the mountain ranges deep into the background that help add to the sense of vertigo of being on top of the world.

All images and video copyright 2015 Universal Pictures.