VFX for The Independent Filmmaker
Updated: May 12, 2022
Visual effects are processes used to manipulate imagery is now the digital post-production process. It is often termed as VFX to create imagery which was once culminated using Special effects. Special effects are effects created within the camera or on the set. In the 1990s there were two prominent types of effects used in cinema. Optical effects and Mechanical effects, Optical effects are effects created using multiple exposures, glass shots, mattes, and optical printers. Optical printing effects are the basis of computer-generated effects used nowadays. Mechanical effects are executed using camera techniques, sets, models, props, and make-up.
With advancements, digital composting came into being and this led to a revolution in Film making. It is a method by which two different imagery sources could be combined. CGI or computer-generated imagery combines animation with photorealistic textures to create unimaginable worlds. An example of everyday composting is Chroma keying or Color keying. Recall the TV weatherman sitting in his studio while the visuals behind him depict different maps and cartographies. It’s the magic of the Green screen and Blue screen. The use of Keying began in the 1930s which was a chemical process employed similarly but that was very time-consuming. In Color keying, a subject is photographed in front of a screen that is either Blue or Green.
Head on a Plate - Optical Illusion
These colors because they oppose the color of Human Skin. Initially, blue screens were used but the advancement in the digital cameras and their higher responsiveness to the luminance values of green color led to the prevalence of green screens. When a film or non-digital video camera is used blue is often preferred. Green Screen is mostly employed for the outdoor shoot because of the sky. Digital information is stored in separate color channels Red, Green, blue, and alpha. The alpha channel controls the transparency of color and in a composite shot, a specific color range could be treated with transparency or removal. Garbage Mattes are used when keying is too difficult. In this process, the compositor's hand draws the area which will be removed in the post-production process.
A shot from The Lord of the Rings: The Return of the King (2003), © New Line Cinema © WingNut Films. Shot with scale models and CGI.
There is another process where every frame is treated in a hand-drawn manner which is called Rotoscoping. In television commercials that are shot on the video format of 30 fps/ frames per second, the rotoscoper has to attend to 1800 frames for a 60-second commercial. The digital world offers various means to simplify this process as well. One of these is motion tracking. By this process, a specific area of the image can be tracked so that some other visual process could be added to it. Another technique is Digital dismemberment. To avoid rotoscoping a key dot is placed on the actor’s body which can be tracked in post-production to add something in place of it.
A shot from A Scanner Darkly (2006) , © Thousand Words © Section Eight © Detour Film Productions © © 3 Arts entertainment. Batch Processing was used to create an animated look for the film.
Another means for such effects is Batch processing where each shot is broken down into individual still images and then an image editor attends each frame to give a certain look to the film. Nowadays most important composting method has become the CGI or CG. CGI has been used since the 1970s but the revolution came along with Jurassic Park where CGI dinosaurs were integrated into scenes with living actors.
A shot from Jurassic Park (1993), © Universal Pictures © Amblin Pictures. This film was revolutionary with its use of Computer Generated Imagery.
Fantasy and Sci-fi genre films like Star Wars were shot in a similar manner where actors' performance was integrated with computer-generated animation. The ease of 3D technology and computer-generated animation has excelled over scale models. Since scale models have to be enhanced in post-production. Even Particle systems are used in these 3D scales to generate fog, smoke, rain, and dust. The VFX artist embeds these elements with the real-world physical environment.
A shot from Star Wars (1977), © LucasFilm Ltd. It is known for its Optical, Visual and Special Effects
This piece is an introduction to the basic VFX elements employed by the Film industry and its brief history. We discussed certain techniques which film-makers can use to enhance their storytelling techniques and create unimaginable worlds. In the next article, we will discuss the tools, software, systems, and techniques that can be used on a cheaper budget. Finally, why should the filmmakers avoid the famous industry slang “let’s do it in post”.