It’s a technique that’s often used for flashback sequences in movies when an older actor plays a much younger version of himself like Kurt Russell did in Guardians of the Galaxy Vol. 2. But the results are never quite perfect, or at least don’t reach the impressive level of pixel perfection that compositor Rousselos Aravantinos did with this 4K digital touch-up that made this model look 30 years younger.
Typically, visual effects studios will cover up parts of an older actor (their hands, face, hair) with full CG replacements to make them appear younger. But that can often lead to results that fall squarely in the creepy uncanny valley. Remember the younger versions of Jeff Bridges in Tron: Legacy? There was something just not quite right about those characters, and while the quality and believability of photorealistic CG humans have improved by leaps and bounds in the eight years since that film was released, the techniques Aravantinos uses for his touch-ups are near impossible to spot.
Instead of creating detailed 3D replicas of a performer, which is an expensive process, Aravantinos uses a piece of 2D digital compositing software called Nuke. You can think of it as a far more advanced version of Photoshop that’s designed to manipulate and process moving images, not just stills. Erasing a wrinkle on someone’s headshot in Photoshop isn’t terribly challenging, but erasing that wrinkle across 150 frames of video while the person is moving is an infinitely more complicated process.
Digital airbrushing, combining blurred layers, cloning, color correcting, and warping are all techniques used to retouch and de-age footage like this. But since the corrections and fixes have to remain on specific parts of the model’s face that are moving around the frame, Aravantinos also takes advantage of Boris FX’s Mocha Pro tracking software which can calculate and reproduce the movements of anything seen in a clip.
The results of Aravantinos’ painstaking work are impressive, and had he not provided a side-by-side comparison with the original footage, it’s doubtful anyone would be able to spot his handiwork. It’s time-consuming work, though, which is why the 3D route is still so popular—at least until someone figures out how to teach a deep-learning AI to automate the digital de-aging process.