During the build-up to the release of the movie, the biggest attraction of Avenger: Infinity War was the various team-ups featured in it. All through the production and promotions, various groups and bonds surfaced that were to be the plotlines of the movie. One such pair was the “facial hair bros,” aka Tony Stark (Robert Downey Jr) and Doctor Strange (Benedict Cumberbatch).
The duo undertook a cosmic trip which saw clashing ideas in action. However, before reaching the endgame stage, they had their very first meeting. The meeting happened quite early in the film and put them alongside Bruce Banner and Wong to protect Earth from two Black Order members, Ebony Maw and Cull Obsidian. This was a huge battle and Downey has now shared a behind-the-scenes video of the shooting.
Downey shared the video on his Instagram and showed how the experience was to film it on the streets of Atlanta. The video is especially meaningful to those who have already seen the film, as Downey is acting in the scene whereas the movie showed Tony in his newest nano-tech Iron-Man suit, which according to his caption is “movie magic.”
Avengers: Infinity War is the latest MCU film wherein he didn’t have to wear a real Iron-Man suit, and the responsibility rested with the Visual effects team to add the suit later. Although they are not totally visible in these shots, set photos of Avengers: Infinity War revealed that his suit had some motion capture dots on it. This implies that the Iron-Man on the screen (at least to some extent) is actually using the on-set physical actions of Downey to portray the movements. Therefore, even if those scenes might not show Downey’s face, it was still him only.
Although this might lead to complications in the post-production, it was vital to use Downey for motion-capture due to the nano-tech suit. As seen in the movie, Stark can instruct the tech to move from one body part to another. During his final battle with Thanos, Stark adjusts his nano-tech to protect his arms more than his legs, and ultimately it led to his face being visible too. In case Tony uses this technology in Avengers 4 or even beyond, this might become the usual way for Downey to film until he comes up with the next technological enhancement.
Source: Robert Downey Jr.