The VES Handbook of Visual Effects

Industry Standard VFX Practices and Procedures

Susan Zwerman, Jeffrey A. Okun

• Publisher: Routledge
• Year: 2014
• ISBN:
  9781136136214
• Edition: 2
• Topic: Art
• Subtopic: Art général

Wisdom from the best and the brightest in the industry, this visual effects bible belongs on the shelf of anyone working in or aspiring to work in VFX. The book covers techniques and solutions all VFX artists/producers/supervisors need to know, from breaking down a script and initial bidding, to digital character creation and compositing of both live-action and CG elements. In-depth lessons on stereoscopic moviemaking, color management and digital intermediates are included, as well as chapters on interactive games and full animation authored by artists from EA and Dreamworks respectively. From predproduction to acquisition to postproduction, every aspect of the VFX production workflow is given prominent coverage. VFX legends such as John Knoll, Mike Fink, and John Erland provide you with invaluable insight and lessons from the set, equipping you with everything you need to know about the entire visual effects workflow. Simply a must-have book for anyone working in or wanting to work in the VFX industry.

1

INTRODUCTION

Michael Fink

 

 

 

First, Some Ground Rules

In this introduction, and in a great part of this book, when the term “visual effects” (VFX) is used, it often applies to the disciplines of both visual and special effects. Additionally, when a project is referred to as a “film” or a “movie,” the reader should understand that the writers mean to address all moving image production that uses visual effects—not just the narrower definition of narrative filmmaking.

Now, the Introduction

What is a visual effect? What is a special effect? The term “visual effect” is used to describe any imagery created, altered or enhanced for a film, or other moving media, that cannot be accomplished during live action shooting, and further expanded to include virtual production—the process of capturing live images and compositing them or reinterpreting them into a scene in real time. This implies that much of the art of visual effects takes place in post-production, after primary image capture is complete. But visual effects artists are intimately involved in the entire production of a film, or a game, television show, webcast, commercial—from the very first days of production. The process of designing, planning, executing, and completing visual effects requires interaction and collaboration with nearly every department on a project. Visual effects can be added to live action capture, or used to create a scene entirely artificially, through techniques such as matte painting, computer graphic objects, characters, and environments, character and effects animation, and compositing of disparate images recorded in any number of ways. Visual effects have become a standard part of every moving image maker’s tool kit.

A special effect, on the other hand, is generally described as any effect that can be done while a live action scene is being captured, and are commonly called Practical Effects or floor effects. In current methodology, special effects go hand in hand with visual effects, such that in the final product it is often very difficult to determine which was a special effect, and which was a visual effect. Examples of special effects are bullet hits, practical explosions, rain, fire, car gags of all sorts, flying rigs, motion rigs that shake or simply move sets or props or vehicles, gimbals to mimic the motion of boats or planes, artificial ocean waves and spray, rain, fog, snow, and of course, slime. The collaboration between special and visual effects has provided new avenues for safe, visually stunning practical effects. For instance, the early acceptance of digital rig removal allowed more freedom for special effects artists to create more elaborate flying rigs on set, while greatly increasing safety for all involved.

The important thing to remember is that today special effects and visual effects artists and technicians work hand in hand during filmmaking. Close collaboration between the visual effects and special effects departments on a production is essential, and lines are blurred constantly. Although the reader might think this is a relatively new development, it is not. The very first visual effect audiences saw on film was The Execution of Mary Queen of Scots (1895). It required the close collaboration of the special effects team to provide a dummy with a severable head, and the visual effects team that executed the “jump cut” technique to make it appear as if the actor portraying Mary truly had her head cut off.

Since the earliest days of the moving image, visual effects developed with, and helped to expand, the film industry. But visual effects have been an equally integral part of the growth of gaming, internet or web media, special venues, and broadcast video. It is important to remember that film may have been the first moving image medium that employed visual effects, but as new technologies developed, visual effects artists have been there to improve the storytelling experience in all media.

The path of visual effects art and technology has been long and interesting. From the development of optical printers in the 1920s, to the introduction of new film stocks, new ways to light, create mattes, do color differencing, use motion control, scan and record film to digital files, create entirely digital images; through the invention of ways to render motion blur, create Alpha channels, track shots, pre-visualize shots, light computer graphic objects so that they are indistinguishable from real, and believably integrate synthetic characters and environments with practically captured environments and special effects—all of these will be discussed in detail in this book.

Why Use Visual Effects?

There are three primary reasons to use visual effects in a film:

The first is when there is absolutely no practical way to film the scenes described in the script. The tiger attempting to climb into the life boat in Life of Pi (2012), or the weightless Sandra Bullock and George Clooney in Gravity (2013) are examples of this.

The second reason to use visual effects occurs when you could shoot a scene practically, but doing so might place someone’s life at risk. The 1926 silent film Fire Brigade contains a scene where a toddler gets left behind in a burning building. It is clear she is surrounded by flames and must be rescued by the heroic fireman. The little girl, however, could never be exposed to real fire. She was shot separately from the fire, and the fire elements and the footage of the little girl were optically composited so that the girl really appeared to be threatened by the flames. This technique allowed for some hair-raising scenes (to 1926 audiences) without risking anyone’s safety.

The third reason arises when it is more cost effective or practical to utilize a visual effect than to film a scene for real, due to issues of scale or location (or both). Examples of this are the Bilbo Baggins’ “adventure” at the Lonely Mountain in The Hobbit: An Unexpected Journey (2012), Spider-Man showing his powers high above the streets of Manhattan in The Amazing Spider-Man (2012), and James Franco in the Land of Oz in Oz: The Great and Powerful (2013). More simply, but very important to the story, shots in Tropic Thunder (2008), which added a bluescreen Ben Stiller performance into a scene long after the location was lost to the production.

Conclusion

Visual effects, if they are done well, are not obvious. At their best, they work to further the story being told, becoming an integral part of what makes us willing to suspend disbelief, and immerse ourselves in the story being told.

Visual effects have allowed filmmakers to take us on journeys to places that have ceased to exist or that have never existed, and to see things that we could only imagine. With the magic of visual effects, we have witnessed stories set on imaginary planets, embraced rich fictional worlds, come to know beasts, devils and angels, robots and talking apes, and brought dinosaurs back to life—not from insect DNA trapped in ancient amber, but from the magical plasticity of digital imagery created by talented visual effects artists.

Computers today provide artists with a powerful tool to create fantastic images, but computers alone cannot make those images. It is the eyes of the artists—their imaginative and innovative use of these new tools—that create the wonderful new worlds in games, on television, on the web, and at the cinema. The magic is really and truly from the artist’s vision. The art of visual effects can serve to change our perspective and instill new understanding of our relationship to the universe. An amazing example of this is the opening scene from the 1997 film Contact, where we travel out from earth’s atmosphere through bands of electromagnetic signals we have sent into space… defining our small corner of the universe … out past exceedingly distant galaxies where our signals will take countless millennia to penetrate—vast, unfathomable distances, at last coming back to the blue eye of a little girl just discovering the wonders of this earth and the “small moves” it takes not to miss anything.

We, the visual effects artists and technologists whose daily lives are dedicated to making magic real, hope you will enjoy this book, and that it serves in some way to enable you to see things in a new light, exercise your imaginative powers, perhaps even join us on this journey to make stories that engage, astonish, and captivate. We are proud of the work we have helped create as makers of movie magic, and we are glad to share our ideas, history, and techniques with you in this book.

2

PRE-PRODUCTION/PREPARATION

OVERVIEW
Scott Squires

The making of a film, commercial, or television show is broken into three main phases:

Pre-production: where all the design, construction, and preparation occurs before any filming is done.

Production: the actual filming of the live action that occurs on a set or location.

Post-production: all the work to complete the project after the filming. This includes editing, sound, music, and visual effects.

Even though the majority of visual effects are done in post-production to augment the shots that were filmed, all of these phases are important to visual effects. During production a visual effects supervisor or plate supervisor is on the set to make sure the live action is shot in a way that visual effects can be added correctly in post-production.

This chapter covers pre-production relative to visual effects. This includes the budgeting of the visual effects and the decisions about what company and visual effects team will work on the show. More importantly, it covers the designs and the techniques that will be used and that will ultimately determine much of the success of the visual effects. Pre-production is also a good time to develop new techniques, test ideas, and start the building of models when possible. Although this chapter approaches many of these areas from a feature film standpoint, the same steps apply to commercials and television production, just in a smaller number of shots and shorter time schedules. Each production is unique, so the issues covered in this chapter are meant as a starting point for a typical production. Budgeting requirements may be a bit different from studio to studio, and some areas, such as previs, are continuing to develop and change.

Production (producer, director, studio) may be reluctant to spend much time on visual effects pre-production, but this can have a huge impact on the cost and quality of the visual effects and the time required. A VFX Supervisor is able to work with the director, producer, and production departments to determine trade-offs for different approaches. This may prevent the construction of large elaborate sets that could be replaced by matte paintings or the use of digital doubles for stunts that could be impractical on the location. The choice of techniques in pre-production will also determine what steps are required during shooting and what can be done to shoot as efficiently as possible. Pre-production costs are relatively small since a smaller team is involved. If design decisions are not locked in before filming, then it is possible the live action may be shot in a manner that will need to be completely changed in post-production when the designs are locked in place. This is not only very expensive but is unlikely to provide the best-quality shots.

BREAKING DOWN A SCRIPT—BUDGETING
Scott Squires

Budgeting visual effects is a difficult and ongoing process because of the number of unknowns associated with visual effects shots. Any assumptions should be listed on any bid, along with the date of the script and any additional materials (storyboards, etc.). Shots will have an average length assigned by default (usually 5 to 8seconds).

To balance the flexibility of editing with the costs associated for animating and rendering visual effects, a “handle” length is usually assigned on a project. These are the number of extra frames at the start and end of each shot (typically 4 to 8). This allows the director and editor some slight adjustment in editing even after a visual effects shot is completed. Without this handle, many shots would have to be redone, which would cost more time and money.

Th...