Directed by Shane Black, Marvel’s third big screen installment of the Iron Man series sees Tony Stark’s world destroyed at his enemy’s hands. What follows is no story of politics, “just good old-fashioned revenge,” as Stark puts it. In just eight weeks visual effects house Framestore delivered 113 shots for the film, working on Iron Man himself and helping set the look for one of the movie’s key effects – Extremis.
Extremis is a drug that confers formidable strength, but gets red hot as it rushes around the body, visibly steaming as it flows through veins and arteries deep below the skin. Much of Framestore’s work on the film came in perfecting the Extremis look for the skull, but other shots required a digital takeover for one of Iron Man’s enemies and the creation of a full CG fire. To do all of that under the constant flux of the edit and on such a small timescale was a fantastic achievement.
“This is the second time I've worked with Framestore, and again, it was an absolute pleasure,” said Iron Man 3 VFX Supervisor Chris Townsend. “They have a truly talented group of artists and a dedicated production team and, from the outset, I was impressed with not only their creative solutions, but also attention to detail and the overall quality of work."
Does the man make the suit or does the suit make the man?
That’s the film’s central question, but in at least one scene, it’s Framestore behind the suit. “The whole team was super motivated by doing Iron Man,” says CG Supervisor Alexis Wajsbrot, and having just finished work on Alfonso Cuarón’s eagerly anticipated space epic, Gravity, it was a smooth process: “We were given the Iron Man asset from Digital Domain and within a week had it looking great in our pipeline,” says Producer Richard Graham. “Part of the legacy of Gravity is that all of our Arnold shaders for metals and hard surfaces are really well matured, and there were no difficulties in look development.”
"We’d got well into the Extremis work before we started on Iron Man,” explains Lighting Supervisor Stuart Penn. "There was a lot interactive lighting between him and the Extremis effect – at one point the enemy grabs him and heats up the suit – so we see heat glow and sparks as the suit is short-circuited. The level of interaction needed the track of the arm to be really good."
Other facilities had already worked on the effect of Extremis on limbs, but many of Framestore’s shots focused on the skull, which required a great deal of look development. Pleasingly, Framestore’s skull shots seem to have set the look for the effect across the film.
“The work by other facilities had been done on the arms where there was quite a bit of structure to play with – for example silhouetting the bones and making light wrap around them,” says VFX Supervisor Mark Bakowski. But whereas the arm was anatomically accommodating, the skull was less obliging. “Finding that formula was the most difficult part,” continues Mark, “the skull is very densely packed and we had to thin that out a little bit to sell it.”
“A lot of work went into making Extremis visually appealing,” says Lead Compositing Supervisor Chris Zeh. “It went through a lot of different concepts and it was nice to hear that our Extremis effect seems to be, out of all the facilities working on it, the one Marvel sent to the others.”
Stripping back from a dense, anatomical skull (which would simply look like a light bulb if you illuminated it) toward something more art directed, the team arrived at an effect that was both believable and interesting. “The main brief was to make it look as if it had volume, as if you were looking deep into the body, not like a something painted on the skin,” says Stuart.
To make sure this was achieved, the whole anatomy of the characters was modelled – from skeletons and muscles right down to blood vessels and capillaries, which resulted in some super heavy rigs (combated by setting up a pipeline that meant each element could be dealt with separately). It was also a big task to deform that amount of geometry and Framestore developed its own deformer to make sure everything would fit inside the skin.
“After rigging and modelling we moved onto tracking, which was a big challenge as there was body and facial tracking in every shot,” explains Alexis. “We started with camera track, body track and facial deformation, using 3D equalizer. The trackers did amazing work in a very short space of time. The team was quite small yet they tracked over a hundred shots!”
From there the FX team began controlling the movement of Extremis by flowing particles along the veins and arteries. “This was very choreographed and art directed, so it wasn’t easy! We needed to have full control on particle speed, flow and direction. That was a set-up done in Houdini by Selcuk Ergen (Lead FX TD) and his team. By the end of the show it was just pressing buttons – it was very successful.”
The flow of Extremis is so hot it emits steam, something created by the Maya team, led by Horacio Mendoza, using a fluid simulation. “The challenge was the deadline,” says Alexis. “It was maximum two days per shot for the steam, so we had to have a very strong set up in order to do fast simulation.”
Lighting obviously played a huge part in revealing the depth Marvel was after. Point clouds were used to drive lighting internally beneath the skin, which was refractive, so the deeper beneath the skin the light was, the blurrier it was.
One of the main challenges Framestore had to face was to be able to reproduce the Extremis effect on four different characters and seven different sequences. The full capacity of the Framestore pipeline was used to create a small factory so that, just by just pressing a few buttons, FX TDs and Lighters were able to update their shots if the model, track or even the look was changed. Framestore used its propriety solver, Flush, to create the long simulation for the fire, which needed to interact with a character walking through it. “In that shot the person is practically full CG, except for the clothes, hair, teeth and lips, we rendered everything, so it’s a full body-track,” says Alexis.
In less than two weeks Framestore completed a digital double takeover for one of the main villains, replacing their entire body in CG from the moment they’re shot to the moment they hit the ground. The scene also required some further regeneration work and a few finishing touches to make sure they looked evil enough to deserve being shot!