Fortunately, Oliver knows how to take a fall and wasn't seriously hurt. So he was able to quickly resume his role as an expendable flesh puppet -- that's what MoCap artists used to be called. We hope affectionately.

"I remember once being asked to do a back somersault and land on my front. The client asked that I do it onto the hard floor so that it wouldn't affect the data. The data! There I was wearing nothing but [spandex] and they wanted me to wipe out on the concrete for the sake of good data. I declined. I've worked with professional stuntmen whose careers include James Bond movies and even they didn't want to work in motion capture because of the punishment we endured."

Capcom
"Now we're going to hit you with this bat just to see how react."

Today the business is much safer, thanks to crazy ideas like "proper equipment," and "regulations," and "some basic human empathy, god damn."

In motion capture, it's common for all the physical movement to be done by one actor, while all the dialogue is done by another. It's kind of like having a stunt double for walking across the room.

Marvel Studios
Which is why the main set for Iron Man 3 was Robert Downey Jr.'s recliner.

"For the video game Until Dawn, named actors recorded the facial and voice performances in Los Angeles, while I and other actors recorded the body performances in the UK. This has been called the Frankenstein effect."

The practice first started because of those reflective ball markers that make MoCap artists look like the world's saddest Christmas trees. According to Oliver, they used to be so incredibly hard that "I would frequently wake up the next day with purple circles in key places around my rather sore body."

Microsoft
"Are you sure these are safe?"
"Safe ... ish."

Back in the day, cameras couldn't actually pick up the motion of the balls on their faces (heh) from a distance. So, "You had to repeat your entire performance a second time in a chair, close enough for the cameras to see the tiny markers."

Celebrities couldn't risk looking like they went six rounds against an octopus just for a lowly MoCap role, nor could they be expected to do every scene twice for such a low profile gig. Even today -- with improved MoCap technology that can pick up finer movements, and doesn't make you look like you lost a paintball war against everybody -- the no-names still do all the gruntwork behind a celebrity motion capture.

New Line Cinema
"Some Guy as Andy Serkis as Chris Pratt coming soon."

"It's cheaper to get [the stars] in for a day and do all the voice-over and facial acting, and then get a cheaper actor in to do the rest."

The "rest" includes stunts, body language, breathing that matches the dialogue -- pretty much everything that makes a human look human. So if you're weirded out by some CGI celebrity appearance, it may not be the quality of the special effects, but because Hayden Panettiere's living head is riding the body of someone who's never even met her.

"Lots of actors would turn motion capture down! To them, it was an inferior medium. I worked on a TV show in my early days and one of the actors had no time for MoCap. He never learned his lines, and used to mumble along to the pre-recorded audio and make general gestures. The data looked awful. It was a common sight back then, people just not taking it seriously. When I would talk to other actors about MoCap they would often shrug and say, 'Yeah, but it's not real acting, is it?'"

That attitude is mostly in the past now, and though the actors might remain mostly anonymous, you know their performances. If you enjoyed Iron Man from the second film, or Ant-Man from ... Ant-Man ... you're at least a partial fan of Oliver's.

Marvel Studios
But if you didn't it's entirely RDJ's and Paul Rudd's fault, respectively.

"I'll never forget the day I was told I was playing Iron Man. I was working with an amazing stuntman, Ashley Beck, and we ended up sharing the role. In post, they stitch it together seamlessly. The same was true for Ant-Man, although that time I was shooting alone."

Don't feel bad if you didn't know it. The intrinsic anonymity is seen as an upside to many MoCap actors:

"Your job is to play the character, or even the other actor, not to play yourself. It's the ultimate disguise! It's nice to get recognition, but at the same time I can definitely live without the kind of attention that celebrities get. I get to have all the fun without the autographs! I wouldn't trade it for anything else in the world."

Marvel Studios
Plus, the sheer number of infants Chris Hemsworth has to consume to maintain his physique just isn't worth it.

And now that MoCap is more mainstream, even the big names show up in the studios. At least the cool ones ...

"I once worked with Liam Neeson in a MoCap studio on A Monster Calls. A very nice fellow! He didn't need any coaching at all."

Fotoramas Magazine
And he was extraordinarily helpful in tracking down the lawn mower Oliver's neighbor had borrowed from him.

We could've guessed that. Liam Neeson doesn't care how many layers of computer animation you throw in front of him; he'll just Liam Neeson straight through 'em and punch that role right in the throat. That's why he's Liam Neeson and you're just somebody in Liam Neeson's way.

Motion capture is not for the shy. Lycra -- the spandex-like material that the suits are made out of -- leaves less to the imagination than fanfiction.

"Lycra is not the most comfortable material to wear to work. There's nowhere to hide in a skintight suit, a fact that causes many actors to freeze up when they walk into the studio for the first time. Shy people don't do so well in motion capture. Put a timid person in a Lycra suit and push them out in front of a room full of guys and they tend to get very nervous. Motion capture will pick that up in a heartbeat."

Zoran
Better hope they don't capture any fear boners either.

You can't have Iron Man subconsciously trying to shield his crotch from the other Avengers. If anything, he'd be highlighting it with a shiny new codpiece. But this is an exhausting job, with no time for modesty. That's actually one of the biggest differences between MoCap and other types of acting -- the sheer speed at which they work.

"There are no sets to construct or move around, no lights, very basic furniture and equipment, and MoCap shoots in 360 3D all the time which means you only need one good shot for all your camera angles, all of which makes it incredibly easy to jump from one scene to the next. As a result, you get through a lot of lines in a day. You also need to stay focused while working in warehouses all day without sunlight, spouting numerous lines of dialogue and acting your heart out, while wearing a heavy helmet with a camera attached to it."

Kevin Winter/Getty Images
"GIVE ME MY OSCAR NOM!"

A week's worth of Hollywood-set-acting can be crammed into one day of motion capture, and that's a lot of running around playing professional pretend. It's obviously physically exhausting, but the emotional toll is heavy, too:

"I was working on on the AAA game Homefront: The Revolution. The first week of shoots was doing torture scenes. Me and the other actor basically took turns to act out horrific acts of torture on each other for four days, 8:30 a.m. to 5:30 p.m. The action was to fill out a vast cityscape of activity that could be viewed by the player depending on how they played. We spent the first morning watching a YouTube video about acts of torture reported by citizens from a particular country and that alone was depressing. It got very uncomfortable and very depressing very fast."

GetMotion Studios
"OK, we gotta watch Charlie Bit My Finger before the next one."

But hey, at least now they have crash pads to collapse on when the depression gets overwhelming.

Oliver Hollis-Leick is an actor specialising in performance capture. He is co-founder of The Mocap Vaults, an organisation set up to teach motion capture to all. Cezary Jan Strusiewicz is a Cracked columnist, interviewer, and editor. Contact him at c.j.strusiewicz@gmail.com or follow him on Twitter.

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