3D Storytelling

How Stereoscopic 3D Works and How to Use It

Bruce Block, Philip Mcnally

• Publisher: Routledge
• Year: 2013
• ISBN:
  9781136038815
• Edition: 1
• Topic: Media & Performing Arts
• Subtopic: Film & Video

3D Storytelling is the ultimate guide for directors, cinematographers, producers, and designers of stereoscopic 3D movies and videos. With an emphasis on the aesthetic over the technical, this book is an essential foundation for showing you how to use 3D creatively to tell a story.

Hollywood producer Bruce Block and Dreamworks stereoscopic supervisor Philip Captain 3D McNally blend their vast real-world experience and teaching skills to help you learn how to: * Think in 3D
* Integrate 3D design into your script or story
* Direct and design the 3D depth of your shots
* Use stereoscopic windows
* Work with the depth cues in 3D
* Create a comfortable viewing experience for the audience
* Plan editing and directorial considerations for 3D
* Understand closed, open, and unstable 3D spaceBrimming with practical information that can be immediately applied to your 3D production, the book also features interviews with some of the industry's leading stereographers, as well as 3D diagrams and photographs that illustrate how 3D works, how it can be controlled in production, and how 3D can be used to tell a story.

Chapter One
The Basics

Thinking in 3D

Stereoscopic digital cinema and television offer unique visual opportunities for storytelling but they also require picture-makers to rethink established filmmaking ideas. The screen is no longer a flat surface displaying a two-dimensional picture. In 3D, the audience is unaware of the screen and it becomes a window suspended within a three-dimensional space. Objects can now appear in front of the window and behind it.

3D is an amplifier for depth. When the staging, composition, and production design constructively exploit 3D, the visual world of three-dimensional depth opens up to the filmmaker and the audience.

3D has its own “visual language.” Before you can speak the language, you must learn a new “visual alphabet.” If you only know part of that alphabet, your ability to create 3D will be limited. Don’t be impatient. It’s not only about learning a new vocabulary, it’s also letting go of some old habits that could keep you from fully understanding and using the 3D grammar.

Like any art form that depends on technology and craftsmanship, there are certain terms and concepts that must be understood. 3D is no different. Once you see and understand the visual possibilities that 3D offers, you can merge them with a story to produce an interesting and unique visual experience.

The first two chapters of this book explain 3D’s technical and aesthetic variables. The third chapter deals with the visual problems and advantages that 3D presents to directors, cinematographers, and designers. The fourth chapter shows you how to use these variables and advantages to tell a story in 3D.

Human Vision and 3D Photography

To explain stereoscopic 3D photography, it’s important to understand how people see in normal, everyday life. As we look around at home, at work, while playing sports etc., we see the world in three-dimensions.

In the real world, we see objects with two eyes. Our eyes look at or converge on an object. The term vergence is sometimes used for convergence.

Because our eyes are about 2.5 inches (63.5 mm) apart, each eye sees a slightly different view of the world. Our brain combines or fuses these two views into a single three-dimensional image.

We only have stereoscopic 3D vision in the center area of our visual field. The left and right sides of our vision are only mono. This happens because the nose blocks one eye from seeing objects on the sides of our visual field. The left eye can’t see objects on the far right and the right eye can’t see objects on the far left.

Stereoscopic 3D photography replaces our two eyes with two camera lenses. This creates a photographic situation that has certain similarities to our own vision system.

Interoccular Eyes and Interaxial Lenses

Human eyes (in adults and children) are about 2.5 inches (63.5 mm) apart. This distance or offset between our eyes is called the interoccular distance (or IO). The interoccular distance can be duplicated with two camera lenses and is called the interaxial distance (or IA).

Like our eyes, two cameras converge on an object. Each camera photographs a slightly different view of an object.

The two photographic views are called a stereoscopic pair.

Stereoscopic 3D Camera Systems

There are two basic camera systems for stereoscopic 3D photography.

I. Toe-in Camera System

This illustration shows an overhead view looking down. The Toe-In system uses two side-by-side cameras angled inward.

Like human vision, each camera lens sees a slightly different view of an object. The two views create a stereoscopic pair. The orange lines at the back of the cameras indicate the position of the image sensors inside the cameras. The Toe-In system is primarily used in live-action photography.

II. Parallel Camera System

This illustration shows an overhead view looking down. This camera system is called Horizontal Image Translation or HIT. Two cameras are placed side-by-side and parallel to each other. The orange lines at the back of the cameras indicate the position of the image sensors, which can be centered or offset. In the above illustration, the image sensors are offset (to capture the slightly oblique image in the frame). A variation on the HIT system offsets the lenses instead of the image sensor. The HIT system is primarily used in computer-generated (CG) animation, however more live-action productions have adopted it. HIT is also used in postproduction to adjust or correct the 3D image.

In the Toe-In or HIT system, the cameras may be combined into a single housing so there appears to be only one camera with two lenses. There are also some hybrid camera systems that combine aspects of the Toe-In and HIT systems.

Camera/Mirror Arrangements

This is not a third system, but an example of an alternate camera arrangement that can be used for Toe-In or HIT systems. The close positioning of two lenses side-by-side for stereoscopic 3D photography can be impossible because the cameras are too large. Mirror arrangements eliminate positioning problems and permit the cameras to be placed as optically close together as necessary.

The above illustration is a side view. The two cameras are arranged above or below each other on opposite sides of a partially silvered mirror called a beam splitter. One camera sees through the beam splitter and the other camera sees an image reflected off the beam splitter’s surface. The two cameras can be aligned on any optical axis without getting in each other’s way and maintain a Toe-In or HIT relationship.

This camera arrangement is sometimes called under/through (or under/over). Depending on the 3D system and rig manufacturer, the assignment of left and right camera positions may be switched. For some circumstances, the cameras can even be mounted at right angles to each other in a side-by-side manner.

3D Viewing

In order to see 3D, the audience must view a stereoscopic pair of images. The stereoscopic pair of images must be separated so that one image is seen only by the right eye and the other image is seen only by the left eye. The stereoscopic pair of images from the eyes is combined or fused by the brain into a single 3D picture.

Historically, most 3D pictures could only be seen by one audience member at a time. The antique stereoscope and the View Master toy are designed for a single user. Each eye is shown a completely separate image, which the single user fuses into a 3D picture.

As of the writing of this book, the best way for multiple viewers and large audiences to watch 3D is to use 3D glasses that separate the left and right e...

Table of contents

• Cover
• Title
• Copyright
• CONTENTS
• Foreword
• Acknowledgments
• Introduction
• 1 CHAPTER ONE - The Basics
• 2 CHAPTER TWO - The Visual Variables
• 3 CHAPTER THREE - The Six Visual Sins
• 4 CHAPTER FOUR - 3D Aesthetics
• Appendices
• Glossary
• Index