The stage is your world: virtual production technology explained
In virtual production, this previsualization step is roughly the same, but the construction of the set takes place in a virtual environment instead of a physical space. This is handled by a specific team, called the virtual art department, which collaborates with everyone from VFX supervisors to carpenters to ensure a seamless blend of digital and real.When the set is created in digital space, virtual scouting can take place. Via this process, filmmakers can explore the space with virtual reality headsets and work out the best angles and shots, just like they would with real-world locations. Movies such as The Jungle Book and Avengers: Endgame used real-time engines for on-set previews of how green screen shots would look in the finished movies.Main virtual production techniquesUse of LED wallsWithout good-quality LED screens, ICVFX would fall apart. These fundamentally rely on the same technology that displays imagery on your TV, monitor, or smartphone, with a few key differences:No bezels: LED stages are created by building literal walls or volumes of multiple panels that seamlessly link together. Bezels are obviously a no-go in this environment, so LED screens feature edge-to-edge displays.Sturdy and versatile: The panels also have to be tough enough to withstand temperamental directors boots and versatile enough to mount in various scenarios, from large flat walls to cavernous volumes, where they can form part of the wall or ceiling.Increased brightness: Film sets are surprisingly bright places. A specialized LED screen is much brighter so it's visible on camera, even with studio lights in front of it, and so it can cast realistic lighting and reflections on physical actors and props. It also has a matte finish to avoid unwanted reflections on the screen itself.Excellent viewing angles: Have you ever noticed how cheaper monitors can look washed out when viewed from a certain angle? This effect would ruin a virtual production, so most LED panels are designed to be viewed from any angle.Low pixel pitch: Likewise, the distance between pixels on the screen (known as pixel pitch) must be as low as possible. If the pixel pitch is too high, theres a risk of a moire effect when the camera is close to the screen, which can cause unwanted wavy or shimmering lines. Today, 1.8mm is considered a good pitch but panels used in the production of Tomorrowland in 2015 featured a pitch as high as 11mm!Color accuracy and calibration: Spot-on color reproduction is essential for seamlessly blending the LED wall or volume with real-world props and actors. For instance, a virtual desert shot might use real sand on set, so its crucial that the colors and lighting match accurately.Rear projection and virtual setsRear projection is nothing new. Those unconvincing shots of actors driving cars against shaky backgrounds in old films made use of this technology by placing a car in front of a projector and replaying footage of a road. Fortunately, its come a long way since then but the fundamental principle is the same.In an ICVFX production, a car can be placed in front of a moving CG landscape to create a convincing illusion that the vehicle is in motion. However, unlike old rear projection systems, the angle, lighting, and content of the backdrop can be changed if necessary. We used this technique to create the moving steam train footage for Ray Tracing FTW.