Getting the Red Planet Right for a Sci-Fi Film That Prioritizes Accuracy

Director Ridley Scott’s film The Martian finds astronaut Mark Watney (Matt Damon) stranded on the red planet with little more than his wits to keep him alive until NASA can rescue him. The film earned more than $500 million at the global box office and received seven Oscar nominations: best motion picture, actor in a leading role, writing, sound mixing, sound editing, production design, and visual effects. The stars were aligned for this one.

We talked with overall visual effects supervisor Richard Stammers of the Moving Picture Company about the film’s photorealistic visual effects. The Martian is Stammer’s 19th film credit and his fifth collaboration with director Ridley Scott. In addition to Oscar and BAFTA nominations for The Martian, Stammers received Oscar and BAFTA nominations for Ridley Scott’s 2012 Prometheus and for last year’s X-Men: Days of Future Past. In addition, he has received four VES nominations, for those three films and for Ridley Scott’s 2010 Robin Hood. 

Stammer shares his Oscar nomination with Anders Langlands, Chris Lawrence, and Steven Warner, and his BAFTA nomination with Lawrence, Warner, and Tim Ledbury. Anders and Ledbury were visual effects supervisors for the film at MPC, Lawrence was visual effects supervisor at Framestore, and Warner was the special effects supervisor. 

Studio Daily: Why do you think your colleagues voted for this film to receive an Oscar nomination for Best Visual Effects?

Richard Stammers: It’s a good film with an engaging story, and the visual effects are an integral part, making it believable. We raised the bar for the work we had to do to take it from science fiction to science fact; we worked with NASA to get the science as accurate as possible. And, I think we have a good, broad spectrum of work that ticks all the boxes in terms of variety.

What was your biggest concern going into this movie?

That we represented Mars in the best possible way. It was important to stay true to what people expected and at the same time make Mars beautiful. It isn’t a documentary; it’s something more romantic. Mars represents the antagonist, the danger, the isolation. The planet surface needed to look fantastic and serve the story.

Photos courtesy Twentieth Century Fox

What was the most difficult visual effects challenge?

The color. Over the years, we’ve seen images of Mars with different color ranges. We had a NASA advisor help us understand the different ways they had captured images and processed them. Trying to understand that was a challenge. The Mars missions use imaging sensors that don’t work like conventional still cameras. They use different color spectrums, a different color range. Mars seen from a Hubble telescope has a different color than Mars from the satellites and from rovers on the surfaces. And many images online have false color. 

What did you settle on as a target for the color?

We found a broad range of images with a yellow sky, which our production designer liked as a starting point, so I went through a process of color-balancing those to make them similar. Ridley does an extreme and beautiful grade to his films that’s important to him, so I did a lot of legwork to get Ridley and the DP [Dariusz Wolski] to agree on a look. We made tentative steps with grading some stills before we started shooting on the green-screen stage. We could preview those as we were shooting. 

How did you match the desired look in post-production?

In post-production, we chose a selection of hero shots from our desert locations and green-screen shots and did a process treatment to put them in the right ballpark. Then Ridley would grade on top, so we had a really good target.

One of the things that helped — it may seem fairly simple — we could have removed the blue sky from the plates through keying, but you get edge artifacts and you need a lot of roto to fix and clean that. And when you change the color of the sky, you still have blue in the shadows and in the haze in the distance. One of my compositing leads came up with a color algorithm, a digital filter that processed the color and turned it to a nice warm yellow, which was a great starting point for Ridley’s grade. There were no noise artifacts, and we could control all the colors in the shadows and in the haze as well. We turned the color algorithm into a Nuke gizmo so our whole compositing team could use a consistent process all the way through. It was really useful.

How much of the film was shot on location in Jordan, and how much on stage?

The shoot in Jordan lasted only 10 days. We scouted Jordan in our prep before shooting, doing digital capture and scanning for the area where the mission stage would be. The location had ground covered with sand and stone that was similar to the Mars images we used as reference. 

But most of the film happened on stage in Budapest. We had a huge green-screen stage. To surround that, we pre-built a digital environment so on set the scouts had great reference. We also loaded panoramas of our digital environment on an iPad so Ridley could have a real-time preview of exactly what the location looked like — where the mountain was, the sun. I could stand next to Ridley and show him what the environment would be.

Did you also do real-time compositing on set?

We had a live composite from the camera, but it saved time to show Ridley the view from the iPad before he moved the camera. We could pan the iPad around, and the view would update to match. It was useful for two things. It confirmed the lighting with our DP, who matched the ideal day we had both liked on the scout — low sun, early morning. And it was useful for compositional decisions, framing, lens size, how much of the background to capture.

We did use simulcam, the live feed from the camera composited with real-time previs, for the end rescue because there was so much blank space and the Hermes spaceship was a huge part of the composition.

How did you film the zero-gravity scenes?

We had little time to shoot and rehearse with the actors so we came up with a nice method. The previs was the starting point. We took that and worked with production design, the art department, and the stunt team. We had a special effects motion control rig driven by electronic winches. Jessica [Chastain] could float carefully down the corridor of the ship and never miss a timing cue for the special effects rig, and the camera was always in the right place. All the actors had to do was concentrate on their performances. 

What cameras were used?

Ridley loves shooting in stereo, so most of the movie was native stereo with Red Dragon and 3ality [Technica rigs]. We also had some 2D work. The shots with Matt Damon recording his video diary were shot on GoPro. All the cast had shoulder-mounted cameras. And occasionally we had GoPro cameras in weird positions. During the sequence when the airlock breaches and explodes, a GoPro attached to the airlock flew through the set.

Ridley Scott is famous for drawing “RidleyGrams.” Did he do many drawings for this film?

He storyboarded the entire movie. He started with four or five drawings per page on the script, and then he filled in the blanks. He’d sit with the previs team and me and in an hour would draw the remaining storyboards. He was drawing something every day on set. Even in post, he’d look at an edit, print out a frame grab, and draw on top. When the rover drives across the flat plain, Ridley did a felt-pen sketch on top of the plate to show where he’d like the dust devils.

Are the dust devils particle simulations?

The dust is a combination of CG simulations and photographs of a tornado machine blowing dry ice around. We created a miniature tornado two feet high and shot it at the right speed to get interesting elements that we combined with CG. The dust storm started with special effects, then we added more layers to balance it across the sequence and increase the stereo depth with particles close to camera. We used a combination of Houdini and Flowline simulations for the storm that engulfs the crew.

Did you put digital doubles in the storm?

[Yes,] during the wide shots. Our most hero digital doubles of Matt Damon and Jessica Chastain were during the end rescue. That was a combination of green- and black-screen shots with the really complicated stunt wire work and digital doubles. The stunts were awesome but we wanted to take out the influence of gravity on the wirework. Also, the wire removals were tricky and, because it was in stereo, the replacement patches had to be technically perfect.

We also had to do fully CG digital doubles of the crew in the opening to create reflections in the visors. The visors were perfect domes that reflected everything you don’t want — the camera, the crew — even when we tried to hide people. We had to do more CG visor shots than we anticipated due to the angle of the helmet and camera. Whatever environment Matt’s in had to be reflected in the visor.

Photos courtesy Twentieth Century Fox

How long was post-production?

We had 24 weeks. We knew going in we’d only have 28 weeks [on the original schedule], so we put things in place to be able to turn things in early. We had a visual effects supervisor on set at all times. We got key builds to the vendors early. Sometimes we had teams on set doing live comps from camera footage to make sure things moved in the right direction. And then the studio wanted an earlier release, so we lost four weeks of our post schedule. That’s when we took on some other companies.

Which vendors worked on the film?

The previs was done by Argon. MPC had the largest shot count and they concentrated entirely on the Mars surface work. Given our short schedule and their experience with Gravity, we gave Framestore the space work. The Senate did the earth-bound effects, the NASA set extensions, [and] the crowd extensions. Later we brought in Milk to add bruising to Matt Damon’s stomach and chest after he was impaled by a bit of the antenna, which involved complex body tracking. ILM did some CG breath and rover driving. Atomic Arts and an in-house team also had challenging sequences. 

How has it happened that you’ve been on five films with Ridley Scott?

He keeps asking. He has a crew of heads of departments that he’s worked with for years and we all understand what he needs. We enjoy working with someone that talented and with that creative energy. He’s a good, energetic, driving force. We all work hard to do something special for him and he appreciates it. It’s hard not to work with someone like that. I’m really proud of our work.