Extending a Decor: (Very) Special Work - Text 7
With the arrival of digital tools, matte painting and three-dimensional models left the workshops of painters and carpenters and entered into specialized software, where they are created either in 2D or 3D, depending on whether there were complex camera placements and movements. At the same time, decor extensions created digitally are now often conceived in a virtual 360-degree environment thanks to the rise of other tools such as virtual cameras and previewing computer generated images at the moment of shooting, known in the trade as “previs on-set,” which make it possible to change viewing angles and camera movements at will and to make the actors improvise. The result, in CGI, will appear in the same way, in real time.[2] Once the mise en scène is approved by the filmmaker, the shot as a whole is recorded and the definitive image completed in post-production and computed in high definition. In this case, like every augmented reality system, the virtual camera makes visible a decor which exists only potentially, calling into question the very manner in which a film is made, because visual effects are at the heart of a film’s creation and everything else is organized around them. With the previs on-set system, the visual effects must be thought out and conceived before the film shoot; they are no longer relegated to the post-production phase alone.
Previs on-set, used increasingly in the production of television series, has also developed in a logic of hybrid production, incorporating green or blue screens for studio backdrops and digital extensions of decors. It makes it possible while shooting to “see” a preview of the final image, a composite image which blends the film image with a computer-generated image by employing, while shooting, a process which, in real time and live, carries out three steps normally done in post-production: tracking camera movements, computing synthetic images and compositing synthetic images with live-action images.
