Artists turn back the clock for actors
Patrick Stewart and Ian McKellen
by Barbara Robertson
X-Men: The Last Stand opens with a flash back, an event that took place around 25 years in the past: The mutants Xavier (actor Patrick Stewart) and Magneto (actor Ian McKellen) meet fellow mutant Jean Gray as a child. Typically, such flashback sequences rank low on a director's list of favorite scenes. To turn back the clock, a director’s options have been to plaster their stars’ faces with makeup and prosthetics or, if the age difference is too great, substitute younger actors. Neither solution is perfect.
TM & © 2006 Twentieth Century Fox. X-Men character likenessesTM and © 2006 Marvel Characters, Inc.
Artists at Lola gave actor Patrick Stewart a digital face-lift foran opening scene in the newly released X-Men using techniques sharpened during the past eight years on music video divas.
Now, there’s a third choice. Thanks to a stealth studio called Lola, director Brett Ratner filmed Stewart and McKellen performing the flashback as if it were any other scene. Later, Lola reversed the actors’ ages digitally in post production.“We filmed the sequence unhindered,”says John Bruno, visual effects supervisor.“The opening sequence is a bit of a ground breaker.”
Ratner filmed the actors on stage—an interior set with a greenscreen window—and in exterior shots. “We did a no-holds-barred process,” says Greg Straus, co-founder of Lola and its sister studio, Hydraulx. “We didn’t have tracking marks. We didn’t limit the actors’ motion, blocking, expressions, or anything. The DP [director of photography]used the lighting he wanted to use. They did everything in-camera the way they wanted. And, we ended up with extreme close-ups: forehead and chin full frame. That meant our work had to hold up on a40-foot screen.”
Lola specializes in what the studio calls “digital cosmetic enhancements.”But X-Men pushed the state of its art. “We had to take 20 to 25 years off these guys,”Straus says. “We pushed into a realm where makeup can’t go. And, that’s the exciting aspect of it.”
The studio initially began performing digital touch-ups for music videos. “In the mid-’90s, music video directors came up with the idea to make their singers look better,” Straus says. “We even out skin texture, take out bumps. Now the diva seven request people by name to do their digital makeup as if they were requesting makeup artists.” Soon, models in cosmetics commercials also wanted digital touch-ups—a bit of blurring here and there to soften flaws and make the actors look better. Recently, Lola began marketing the flattering techniques to the feature-film world.“
We had one or two films the first year, four or five the next, and have 12 this year,” says Straus. “I can’t give examples, because most of the work is strictly confidential—they don’t want people to know who looked good and who looked bad. That’s why X-Men is so cool. We took a vanity tool set and applied it to support the story.”
Digital Skin Grafting
Particularly for film, Lola developed a proprietary technique it calls “digital skin grafting.” “The approach we took for music videos and commercials—blurring out the skin pores and throwing grain on top—makes everyone look younger, but it won’t cut it in a feature film,” says Straus. “It makes people look like they're wearing masks.”
Straus describes digital skin grafting as a 2D and 2.5D technique that utilizes a pipeline based on Autodesk Media and Entertainment's Discreet Flame and Inferno systems. The process, according to Straus, maintains the actor’s expressiveness and performance, as well as such skin details as pores, lines, and subtle wrinkles. “One thing we’ve learned after working on a dozen movies or so is that maintaining the texture of the skin is the most important aspect,” he says. Not necessarily, however, the skin from the actor getting the makeover.
Digital skin grafts drawn from a proprietary library of skin elements helped smooth actor Ian McKellen’s craggy face, and warping
techniques applied in Inferno changed his facial topography. The end result is a younger version of the mutant character Magneto.
Lola artists can draw from a proprietary library of skin elements for the smooth 2.5D high-resolution skin patches that they place on footage of an actor’s face to, for example, fill in deep lines. Although painters might refine individual patches, the age reversal process Lolaused for X-Men does not involve frame-by-frame hand painting. Rather, artists graft the skin patches and change facial topography using warping techniques.“
It’s parametric,” says Straus. “We didn’t write custom software. We built everything as an Inferno batch setup. We’re able to make tweaks by moving sliders.”
The trick, Straus believes, is in knowing how to apply the Inferno tools in the right order—experience gained from eight years of digital touch-ups for commercials and music videos, and three years working on film, and in having built the skingraft libraries over the years. In the case of X-Men, the crew also did extensive research.
The Years Melt Away
It was easy to discover what Stewart and McKellen looked like as younger men: Each actor has a large body of television and film work, plus portfolios of numerous photographs, magazine covers, and so forth. But, in addition to reference photography, Lola artists worked with a plastic surgeon. “Looking at a photograph is subjective,” says Straus. “You don’t know if someone looks younger because of their expression or a physical change. The plastic surgeon helped us understand what happens to faces as they age.”
Artists applying the digital skin grafting techniques used to make Patrick Stewart (at left in images) and Ian McKellen
(at right in images) look younger consulted with a plastic surgeon to avoid making the men look androgynous.
The surgeon also helped the artists avoid an important mistake that even occurs in real-world plastic surgery: making a face look androgynous. “Men and women age differently,” says Straus. “In an early test, we had made one of the actors look younger, but he looked weird. The surgeon taught us it was because we had made a masculine feature feminine. It's very easy to make someone look gender-nonspecific.”
Although the artists used photo documentation of the actors, they didn’t scan the 60-year-olds to create their youthful faces.“Using their own skin wasn’t going to get us there,” says Straus.“We had to go to our library of skin.”
Each actor presented unique challenges. For example, one trick for making someone look young is to add hair, but Stewart's character had to be bald. “We had to go to 30 years younger to have the audience believe he was 25 years younger,” Straus says. McKellen’s craggier face, on the other hand, required more digital skin grafting.
Lola artists produced light, medium, and heavy versions of each actor’s rejuvenated faces, with “heavy” the most altered—cheekbones raised higher, nose or ears smaller, lines erased. “We could ask the director which version he liked best,” says Straus. “If we were painting, there’s no way we could have had as much back and forth.”
Then, working with scanned live-action plates, they created full-motion tests for nervous studio executives who were ready to cut the sequence if the age reversal wasn't convincing.
As the shot begins, the techno crane booms up over Stewart, who is spinning. Then, the camera backs up. “Where it gets tricky is when the guys move their heads in3D and the lighting responds and moves over the work we’re doing,” says Straus. “That’s what separates the men from the boys. In the opening shot, there is full 3D movement of patches tracked onto the actors, and the patches respond to the lighting. That’s the real trick—obeying the lighting in the scene. That’s what makes this stuff not easy.”
The quality-control work is exacting;the work can be tedious. Although the process doesn't demand unique tools—it's based on the clever use of existing tools—Straus believes that the Lola artists’ wealthof experience gives his studio a competitive advantage, one they’ll need now that they've opened the door to new possibilities. Artists using digital tools can deform and change the shape of actors’ faces; they can make them look gaunt and thin—something impossible to do with prosthetics. And, that makes new kinds of stories viable.
“I think this could cause a fundamental shift,” Straus says. “Writers have stayed away from flash backs because directors don’t like casting other people. This could break open a fresh wave of ideas that had been off-limits.”
Barbara Robertson is an award-winning writer and a contributing editor for Computer Graphics World. She can be reached at BarbaraRR@comcast.net