How Robert Downey Jr. was transformed into a teen in 'Captain America' using special effects

Marvel

Warning: There are spoilers ahead for "Captain America: Civil War."

Robert Downey Jr. is delighting the audiences rooting for #TeamCap in "Captain America: Civil War." He's been playing the role of Tony Stark since 2008's original "Iron Man," but took the role to a new level during a flashback sequence where he plays a version of the character 30 years younger. 

In the key scene, we see a teenage Tony Stark speaking with his parents. Interestingly, Marvel chose not to recast the part. Instead, the 51-year-old actor played teen Tony himself. Speaking to The Hollywood Reporter, Trent Claus, visual effects supervisor at Lola VFX, revealed how they were able to reverse the clock on the veteran actor. 

"It is a similar process to Photoshop that uses some similar tools," Claus explained, "but unlike Photoshop which is done on a single image, we have 24 frames per second of footage."

Instead of using a digital double, Downey shot the scene normally and the effects team used digital compositing to apply the de-aging effects to the actor's face in post-production. Claus said this let them retain Downey's "performance and nuances" even after extensive effects. 

For the scene, Lola analyzed footage of Downey from his younger years. There was plenty to choose from, Downey began acting in the early '80s. But that brought its own challenges.

"... When working with the appearance of a well-known actor such as Robert Downey Jr.," Claus explains, "there is the added pressure of living up to the youthful appearance that audiences remember." 

MarvelThe Lola VFX team was also behind the de-aging effects of the 2008 drama, "The Curious Case of Benjamin Button," winning Academy Awards for both Best Makeup and Best Visual Effects. Claus went into detail on how delicate the digital compositing process is:

"Every feature of the face and body needed to be addressed in some fashion," Claus told THR. "One thing that happens to all of us is that the skin of the face gradually lowers in certain areas, and needs to be 'lifted' back to where it was at the age in question."

Lola honed in on minute details in Downey's face to make sure the younger Tony looked natural. 

" ... Other changes are incredibly subtle, such as increase in the way light reflects off the sheen of the skin, a reduction in the appearance of tiny blood vessels under the surface of some parts of the face, or more blood flow in the cheeks giving them that familiar youthful 'glow.' "

The effects were nearly unnoticeable, which, for visual effects teams, is a huge compliment. 

Read the full Hollywood Reporter article here. 

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