In 2014, Richard Stammers had explained to us his work on X-MEN: DAYS OF FUTURE PAST. He now talks about his new collaboration with Ridley Scott for his film THE MARTIAN.
You have worked on many projects with director Ridley Scott?
Yes, this is the 5th movie I have worked on with Ridley: ROBIN HOOD, PROMETHEUS, THE COUNSELOR, EXODUS and THE MARTIAN.
How was this new collaboration?
Great, as always! Having completed a few projects together now there’s a short hand from our collective experiences, and a trust, that comes with high expectations! Every meeting or discussion always comes with Ridley simultaneously drawing his ideas as he goes. From that point of view, it was a great process; there was always an understanding of what he wanted. Things were very clear visually.
What was his approach and expectations about the visual effects?
Ridley is very accepting of complex visual effects processes and techniques and knows most things are possible with time and money. Despite this he does like to get as much in camera as possible. For example he was keen to shoot our zero gravity sequences as practically as possible, believing that a tangible approach was more engaging for the cast. This involved extensive set builds for the interior corridors and complex wire work for the actors.
Can you describe to us one of your typical days on-set and then during the post?
On-Set: At call time we’d discuss the days work with Ridley and the HODs then with my on set team, and make sure we were prepared for each of the VFX set ups that we knew about that day. We also tried to be ready for the ones we didn’t know about, or shots that may develop in to new VFX requirements! We had a great data team who captured and collated all the necessary references like HDRI and witness camera footage, lidar scans and camera/rig data. For the most part, my VFX shoot supervisor Matt Sloan was always there to oversee the smooth running of our capture workflow and be on hand for Ridley and the crew to make sure we got the plates we needed. This would free up time for me so I didn’t have to be on set constantly, which gave me time to oversee other matters that were happening concurrently like previs and tech-vis, planning ahead for next weeks shoot or even spending time back in London with our vendors.
In Post: Most days were filled with back-to-back reviews of work in progress. We would visit our vendors or cineSync from our office 2-3 times a week, each review being 2-3 hours usually. We would aim to review new shots or significant changes to shots with Ridley and the editorial team as often as possible, every day or so. When we had a big enough batch of shots (about 50) to show Ridley for final then we’d screen them at Company 3 so he could see them in a DI environment, graded by his colourist, Stephan Nakamora.
What was your approach on this show?
THE MARTIAN proved to be a highly innovative production, built around speed to accommodate its short schedule. The movie was completed in one year with only a 24-week postproduction schedule. 1100 stereo shots where completed with the work divided neatly between 3 main vendors. As lead vendor MPC‘s work focused on Mars, while Framestore concentrated on space and The Senate dealing with Earth bound VFX work. Our in house team, Atomic Arts, ILM and Milk, also worked on additional sequences.
Work commenced in the UK in August 2014 with pre-visualisation being undertaken by Argon with Jason MacDonald as previs supervisor. Working closely with Ridley we worked out the main action sequences that were vital to planning the shoot, which in turn could inform set builds, stunt wire rehearsals, and lighting continuity. We turned over batches of shots throughout the shoot, and during the first few weeks of post – essential to getting the show delivered on time. We also completed 800 temp shots during the directors cut period, which help enormously to progress the edit, and gave Ridley a solid cut with no holes of untreated VFX shots to present his first pass to the studio.
Can you explain in detail about the creation of Mars and it’s environment?
One of the most interesting challenges was creating the look of Mars. There is a wide range of NASA Martian imagery that suggested many different options depending on how the white balance of each image is interpreted. The colour of the ground could appear red, brown or yellow, with the skies yellow, grey or pink.
Knowing Ridley’s favored location for exterior views of Mars was going to Wadi Rum in the Jordanian desert helped hone the look. We referenced the NASA imagery that most closely matched our location photos and colour matched them to Wadi Rum. This gave them an Earth like white balance, which informed us on which way to proceed with the colorising process for our location photography and digital set extensions of the Martian surface. With the ground colour matching well, the sky colour of the Mars images became grey with a hint of greenish yellow so this became our target point for our comps.
To facilitate this process, the MPC compositing leads developed a sophisticated colour algorithm filter called ‘Earth to Mars’ which gave us fine control to selectively remove the Earthly blue from our shots in a better way than conventional keyers or spill suppression tools. Blue bounce light from the sky polluted haze, shadows and reflections in all our exterior plates so the ETM filter was essential to finding the right balance. This tool also allowed us to accentuate the sky gradation to give deeper, richer colours. This gave us the most realistic representation of Mars, and allowed Ridley latitude to grade the shots redder or yellower which enhanced the ground colour and took the sky colour to the hues of butterscotch and copper that he preferred from NASA imagery.
The skies were an important feature for Ridley, and our work did not stop there. Building upon the fact that Mars has Co2 ice clouds and numerous dust storms we generated a library of sky textures to fit Ridley’s brief. This was to create fine lines of fast moving strata, some of which were white and some were treated as high altitude dust streams. Using Maya fluid simulations as a base and augmented with practical pouring salt elements, sequences of animated strata were carefully composed in Nuke for the most dramatic effect.
Despite Wadi Rum’s epic beauty, it was plagued with un-Martian like bushes everywhere you looked, to the point that every shot required substantial ground replacement. We took this opportunity to add scattered rocks and craters to further enhance the Martian look. Further atmospheric effects such as tornadoes and dust devils were also created for some shots with Houdini simulations and combined with multiple practical dust elements in the final composite.
Can you tell us more about the shooting of the sequences on Mars?
Matching the studio to the location shoot was one of our biggest creative challenges. Whilst we had many scenes that were shot in the studio, many of these required completing on location with wider vistas of the surrounding areas. This often meant our final scenes were intercutting between green screen shots and practical location shots. Having the preview of our virtual environment really helped to set the lighting for the stage work, with our DP Dariusz Wolski who opted to light the scenes with a single high key light source. This gave strong singular shadows and was most consistent with early morning at our Jordanian location. The downside to this was the fall off in brightness of the light source across the length of the stage, which meant selective grading through the bespoke mattes was required to balance the brightness of the studio terrain and facilitate the best blend to the sun-lit landscape in the digital extension.
The heroes are confronted to a major storm. Can you tell us more about its creation?
The wider shots of the approaching storm were created as Houdini and Flowline simulations, generated to flow over and around our CG mountains of the digital environment, all composited behind an FG green screen element from our studio shoot. Once we are engulfed by the storm, daylight is obscured and we change to a largely practical approach with a dark and smoky studio, as a base to vermiculite particles being blown by an array of large fans. VFX augmentation was necessary to all shots by adding further layer of particles to increase the density, stereo depth and jeopardy to the actors, as they make their way to the MAV (Mars Ascent Vehicle). Each of the actors were also attached to a single wire to hinder their movement through the storm allowing then to lean into the wind and get ‘buffeted’ by pulls on the wires by the stunt team. Composting of the additional layers was particularly challenging to get the right perception of stereo depth, as this had to blend with the practical layers in the plates. We also had to integrate the antenna debris, the CG MAV and its rotating beacon light in to many of the shots. Additionally, we also created a number of full CG shots to show the wider geography of the scene and also closer shots of the MAV as it struggles to stay upright in the storm.
Many times in the movie we see the Rover from space. How did you create those beautiful shots?
I shot specific helicopter plates together with aerial DP John Marzano in Jordan. In some cases, the MPC team comped rover elements shot specifically for this, and in some cases we added a CG rover to shots. A few of the shots had the rover driving practically too. When the main unit took a day off John and I utilized the rover availability and with a splinter unit ground team, photographed much of the rover’s journey from the air whilst the splinter unit captured driving shots from the ground.
How did you collaborate with the NASA teams?
Ridley and Arthur Max, our production designer, had meetings with NASA during pre-production which helped inform the details for set design, the configuration of our space ships and information on Mars. We also had a NASA advisor with us during the shoot that was on hand to help with any queries that would arise.
The astronauts have a beautiful ship, the Hermes. Can you explain in details about its creation?
The Hermes was our biggest build, and was actually the most complex digital asset built at Framestore to date. The production art department led the initial design, with advise from NASA on how the component modules would be most practically placed. The final build was handed over to Framestore early on in production where it was flourished with immense detail. Everything needed to be grounded in reality to keep the movie more science-fact rather than science-fiction, so details were drawn form existing space craft design, such as the International Space Station (ISS). Hermes has a modular structure too, based on the knowledge that it would theoretically need to be launched in stages, and pieced together in orbit. The solar panels were are prominent feature of the Hermes design and were a complicated CG challenge for Framestore’s teams. Made of various layers of materials – silicone, plastics and metals – the panels were continuously reflecting and refracting and responded differently depending on distance, light and angle. The lighting team produced great renders through Arnold, and the comp team used very controlled amounts of convolve and glow to beautify the shots. The Framestore team also developed a lens flare tool, which digitally matched the flares we captured in camera which were used for continuity across our space sequences.
How did you handle the zero G shots inside the Hermes?
For our most complex zero gravity moments we pre-visualised the actions to understand the technical shooting requirements. This informed decisions on stunt rig requirement and placement, floating walls and ceilings for access points on our set builds and where we needed special effects motion rigs.
During our first scene inside the Hermes commander Lewis’s journey takes us from the cockpit to the rec room in the spinning gravity wheel. Ridley wanted to achieve this with as few edits as possible so we planned Jessica Chastain’s path through the corridor and into the rotating junction in one stunt. Based on our previs the set was designed to accommodate the stunt wires and the special effects rigs needed to rotate the set. Successful choreography of our cameras, set rotation speed and stunt winches that propelled our actors came about from a harmonious synergy of all equipment working from exported data from our previs scene. Our virtual production supervisor, Casey Schatz oversaw this process and expanded further into other scenes to allow the stunt team to work from preset moves already calculated in our previs. This worked both ways so when the stunt team adjusted or improved the performances these movements could be re-incorporated into our previs.
Can you tell us more about your collaboration with the various VFX Supervisors?
We had a great supervisory team. We’d always try to get them out on set or location where possible, to be involved with their sequences and decisions that may help or hinder their teams later in post. It’s really important to be inclusive and rely on the collective experiences of the whole team.
How did you organize your team to ensure the consistency of the shots look?
With the work clearly divided between our main 3 vendors, consistency with in sequences was rarely an issue. MPC and Framestore only shared one asset, the MAV, which was used during Watney’s final rescue. As the MAV exits the Martian atmosphere into space there is a hand off from MPC’s MAV to Framestore’s MAV. With MPC doing the view of Mars from the surface and Framestore creating Mars from space we had to make sure we harmonised our looks here too. The colour of the planet was informed from our look development and grading of Jordan location plates, and so this was used to assist the colour choices of the planet from space. As our surface shots were based on real photography in the Jordanian desert, I chose to blend in satellite images of Earth’s deserts as textures to the shots of Mars from space. This helped enormously in giving a tangible realism to the shots of Mars from orbit, and linked the 2 looks successfully.
What was the biggest challenge on this project and how did you achieve it?
The short schedule was probably our biggest challenge on the project. Previous films that I worked on with Ridley usually took 18 months to complete, this one we finished within a year. We had a 24-week post schedule (compared to PROMETHEUS’s 34 weeks) so an efficient workflow was essential. Nearly every decision or choice we made had to be right first time, as there would be little time for changes.
Stereo re-times are also a headache for us. Ridley wanted Watney to have a slightly floaty look to his movement in Mars’s is lower gravity, so he had Matt Damon walk faster whilst we filmed him slightly slo-mo. The ideal frame rate would’ve been 32 or 36 frames per second but our stereo rigs could only sync at 48fps so many retimes were necessary to get his walking speed correct. So before we could start any of the VFX work we have to do many interpolated stereo re-times which required significant clean up to remove many of the unwanted artifacts.
Was there a shot or a sequence that prevented you from sleep?
A 24-week post!
What do you keep from this experience?
Short post schedules are really hard! They require meticulous planning, a great support crew of coordinators, early turnover of shots and a strong commitment from all involved. Every decision carries great weight, as there is rarely time to change course!
What was the size of your team?
For all our VFX vendors we had a total of 700 artists working on the show.
A big thanks for your time.
// WANT TO KNOW MORE?
– MPC: Dedicated page about THE MARTIAN on MPC website.
© Vincent Frei – The Art of VFX – 2015
