xv Part I Lighting Theory Chapter 1 Properties of Light.. 96 mr Area Light Parameters Rollout Area Omni Lights.. 101 mr Area Light Parameters Rollout Area Spotlights.. 112 Photometric Li
Trang 23ds max ® Lighting
Nicholas Boughen
Wordware Publishing, Inc.
Trang 3Library of Congress Cataloging-in-Publication Data
Boughen, Nicholas.
3ds max lighting / by Nicholas Boughen.
p cm.
Includes index.
ISBN 1-55622-401-X (pbk., companion CD-ROM)
1 Computer animation 2 3ds max (Computer file) 3 Computer graphics I Title TR897.7.B665 2004
CIP
© 2005, Wordware Publishing, Inc
All Rights Reserved
2320 Los Rios BoulevardPlano, Texas 75074
No part of this book may be reproduced in any form or by any meanswithout permission in writing from Wordware Publishing, Inc
Printed in the United States of America
on the property of others The publisher recognizes and respects all marks used by companies, manufacturers, and opers as a means to distinguish their products.
devel-This book is sold as is, without warranty of any kind, either express or implied, respecting the contents of this book and any disks or programs that may accompany it, including but not limited to implied warranties for the book’s quality, per- formance, merchantability, or fitness for any particular purpose Neither Wordware Publishing, Inc nor its dealers or distributors shall be liable to the purchaser or any other person or entity with respect to any liability, loss, or damage caused or alleged to have been caused directly or indirectly by this book.
All inquiries for volume purchases of this book should be addressed to WordwarePublishing, Inc., at the above address Telephone inquiries may be made by calling:
(972) 423-0090
Trang 4Being a man with a family who sees too little of him,
I must dedicate this book, of course,
To my wife, Victoria,And to my children, Michael and Katherine,
Who have asked for attention so many times
While I sat,Zombie-like,Glued to my evening’s work
iii
Trang 5This page intentionally left blank.
Trang 6Acknowledgments xiv
Introduction xv
Part I Lighting Theory Chapter 1 Properties of Light 3
Intensity/Luminosity 3
Color 5
Direction 7
Diffuseness 9
Shadow 11
Shape 12
Contrast 13
Movement 15
Size 18
Chapter 2 What, Where, When? 20
Interior or Exterior 20
Time of Day 23
Time of Year 24
Atmospheric Conditions 25
Chapter 3 Light Sources 28
Sunlight 29
Skylight 35
Incandescent Light 37
Fluorescent Light 38
Reflected Light 38
Diffuse Reflected Light 39
A Note about Proportion and Scale 40
Chapter 4 Basic Material Considerations 42
Color in the Real World 42
Specularity and Glossiness 44
Reflectivity 47
Diffuse Color 49
Luminosity 51
Chapter 5 Studying Light 54
Natural Light 55
Sunlight 55
Skylight 57
Cloudy Day 58
v
Trang 7Moonlight 58
Starlight 59
Artificial Light 59
Incandescent Sources 59
Diffuse Sources 60
Point Sources 60
Fluorescent Sources 60
Shadow 61
Light Color 63
Chapter 6 Principles of Lighting 64
The Key Light 65
The Fill Light 65
The Highlight 66
McCandless Lighting 68
Key/Fill Lighting 70
Three-Point Lighting 71
What Is Great about Three-Point Lighting 72
What Is Not So Great about Three-Point Lighting 73
Four-Point Lighting 73
Other Lighting Angles 74
Coloring Your Light 76
Complementary Tint 76
Related Tint 77
Intensity Ratios 77
Options in Lighting a Scene 78
Part II 3ds max Lighting Tools Chapter 7 Standard Lights and Typical Uses 81
Default Light 82
Ambient Light 83
Free Lights and Target Lights 86
Directional Lights 87
Directional Parameters 88
Light Cone 88
Show Cone 89
Overshoot 89
Hotspot/Beam 89
Falloff/Field 89
Circle/Rectangle 90
Aspect 91
Bitmap Fit… 91
Spotlights 91
Omni Lights 92
Contents · · · ·
vi
Trang 8Chapter 8 mental ray Lights 95
mr Area Omni Lights 96
mr Area Light Parameters Rollout (Area Omni Lights) 97
On 97
Show Icon in Renderer 97
Type 98
Samples 100
mr Area Spotlights 101
mr Area Light Parameters Rollout (Area Spotlights) 101
On 101
Show Icon in Renderer 102
Type 102
Radius, Height, and Width 102
Samples 103
Chapter 9 Photometric Lights 104
The Good… 104
The Bad… 104
…and the Ugly 104
Photometric Light Types 105
Point Lights 105
Area Lights 107
Linear Lights 108
IES Sky 109
IES Sun 111
Daylight System – Simulated Direct Sunlight Plus a Photometric Skylight 112
Photometric Light Parameters 113
Photometric Light Presets 114
Exposure Control (Environment Control) 114
Chapter 10 Other Lighting in MAX 116
Light Tracer and Radiosity (Default Scanline Renderer) 116
Caustics 118
Volume Lights 118
Objects as Lights 121
Lens Flares 125
Lens Flares Defined 125
Why Not to Use Them 126
Good Uses for Lens Flares 127
Chapter 11 Manipulating Lights 134
Creating Lights 134
Selecting and Transforming Lights 135
Selecting an Item 135
Moving an Item 137
Rotating an Item 138
Scaling an Item 140
· · · · Contents
vii
Trang 9Transforming Target Lights 143
The Light Viewport 143
Light Navigation Controls 144
Dolly, Target, Both 144
Light Hotspot 145
Roll Light 147
Light Falloff 147
Truck Light 149
Orbit, Pan Light 149
The Light Lister 150
Chapter 12 General Light Parameters 152
General Parameters Rollout 153
Light Type 153
On 153
Type 154
Targeted 154
Shadows 155
On 155
Use Global Settings 155
Shadow Type 156
Exclude 156
Intensity/Color/Attenuation Rollout (Standard Lights) 159
Multiplier 159
Color Swatch 160
Decay 161
Type 161
Start 162
Show 162
Near and Far Attenuation 163
Use 164
Show 164
Start/End 164
Intensity/Color/Distribution Rollout (Photometric Lights) 165
Distribution 165
Isotropic 165
Spotlight 165
Diffuse 165
Web 165
Color 166
Kelvin 166
Color Swatch 167
Filter Color 167
Intensity 168
Resulting Intensity 168
Multiplier 169
Contents · · · ·
viii
Trang 10Linear Light Parameters Rollout 169
Area Light Parameters Rollout 170
Shadow Parameters Rollout 170
Object Shadows 170
Color 171
Density 171
Map 172
Light Affects Shadow Color 173
Atmosphere Shadows 173
On 174
Opacity 174
Color Amount 174
Atmospheres & Effects Rollout 174
Advanced Effects Rollout 175
Affect Surfaces 175
Contrast 175
Soften Diff Edge 177
Diffuse/Specular 177
Ambient Only 178
Projector Map 179
Chapter 13 Shadow Types and their Typical Uses 181
Shadow Maps 181
Shadow Map Parameters Rollout 181
Bias 181
Size 182
Sample Range 182
Absolute Map Bias 183
2 Sided Shadows 183
mr Shadow Maps 183
mental ray Shadow Map Parameters Rollout 183
Map Size 183
Sample Range 184
Samples 184
Ray-traced Shadows 184
Ray Traced Shadow Parameters Rollout 185
Ray Bias 185
2 Sided Shadows 185
Max Quadtree Depth 186
Advanced Ray-traced Shadows 186
Advanced Ray Traced Parameters Rollout 186
2 Sided Shadows 186
Shadow Integrity 187
Shadow Quality 187
Shadow Spread 187
Shadow Bias 188
· · · · Contents
ix
Trang 11Jitter Amount 188
Area Shadows 189
Area Shadows Parameters Rollout 189
Basic Options 189
Antialiasing Options 190
Area Light Dimensions 190
Chapter 14 Radiosity 191
Radiosity Defined 191
Global Illumination Defined 191
The Tools 192
Radiosity 192
Radiosity Tutorial 193
Light Tracer 197
A Short Light Tracer Tutorial 198
Another Short Light Tracer Tutorial 200
mental ray Indirect Illumination 204
mr Global Illumination Tutorial 205
Chapter 15 Texture Baking and Light Painting 209
Texture Baking 209
Texture Baking Tutorial 210
Light Painting 222
Light Painting Tutorial 223
Chapter 16 MAX Color Selection Tools 229
RGB 230
HSV 231
HSB 232
HSW 233
Kelvin Color Picker (Photometric Lights) 233
Kelvin and Filters 234
Chapter 17 HDRI and Caustics 235
What Is HDRI? 236
Why Should I Use HDRI? 237
Lighting a Scene with HDRI 238
How Do I Use HDRI to Light a Scene? 239
Using LightGen 239
Using an HDR Image 241
Caustics Defined 248
When and Where to Use Caustics 251
Chapter 18 Rendering 252
Default Scanline Renderer Panel 252
The Common Tab 253
The Renderer Tab 255
The Render Elements Tab 256
Contents · · · ·
x
Trang 12The Raytracer Tab 257
The Advanced Lighting Tab 258
Light Tracer Parameters 259
Radiosity Parameters 260
mental ray Renderer Panel 261
The Common Tab 261
The Renderer Tab 261
The Indirect Illumination Tab 262
The Processing Tab 263
The Render Elements Tab 264
Part III Creating Lighting Chapter 19 Intent and Purpose 267
Understanding Artistic and Emotional Intent 268
What Is Your Light’s Motivation? (Justifying Choices) 269
Chiaroscuro: The Use of Light and Shadow 270
Some Examples 271
A Pleasant Scene 272
A Sad Scene 273
A Frightening Scene 273
Chapter 20 Color Mixing 275
Two Types of Color 275
The Color of Light 275
The Color of Pigments 277
Pigments in the Real World 278
Pigments in MAX 279
RGB Values 280
Hue, Saturation, and Value 281
Hue 281
Saturation 281
Value 282
How Hue, Saturation, and Value Interact 283
Recapping HSV 283
The Additive Color Wheel 284
Primary Colors 286
Secondary Colors 288
Tertiary Colors 288
Intermediate Colors 289
Color Harmonies, or Schemes 289
Monochromatic Harmony 290
Complementary Colors 291
Split Complementary 292
Double Split Complementary 294
Analogous Color Harmony, aka Related Tints 295
Triadic Color Harmony 296
· · · · Contents
xi
Trang 13Additive Mixing 298
Missing Color 299
Subtractive Mixing 300
Subtractive Light Mixing 301
Mixing Light with Pigments 302
The Psychology of Color 302
Warm Colors 303
Red 303
Orange 303
Yellow 303
Cool Colors 304
Green 304
Blue 304
Purple 304
Black 304
White 304
Other Colors 305
Related Tints 305
Complementary Colors 305
Triadic Colors 306
Monochromatic Colors 307
High-Saturation, High-Value Colors 307
Low-Value Colors 307
Low-Saturation Colors 307
High-Contrast Color Combinations 308
Low-Contrast Color Combinations 308
Designing with Color 309
Chapter 21 Mood Setting 310
Angle and Shadow 311
Contrast 314
Intensity 315
Motion 316
Weather 316
Chapter 22 Style 318
What Is Style? 318
So What Do I Do? 319
Less Is More 320
Consistency between Shots 320
Chapter 23 Designing Lighting 322
The Design Process 322
Script Analysis 322
Understanding the Story 323
Research 325
Historical 325
Visual 326
Contents · · · ·
xii
Trang 14Technical 326
Dramatic 327
Discussion: Working with the Design Team 327
Planning 329
Sketches and Drawings 329
The Magic Sheet 331
A Formal Lighting Plot 332
A Formal Lighting Schedule 335
Implementation 337
Block Placement 337
Roughing Out 338
Fine-Tuning 338
Working with Materials 339
Evaluation 339
Balancing the Scene 340
Focus and Emphasis 342
Designing with Light and Shadow 342
Designing with Light 342
Designing with Shadow 343
Lighting a Scene vs Lighting an Object 343
Putting It All Together (Making a Pleasing Picture) 344
Saving and Reusing Lighting Rigs 345
Chapter 24 Identifying and Recreating Light Sources in a Plate 346 About Photo-real Lighting 346
About Plates and Light Sources 347
Replicating the Light Source 350
The Mirror Ball 357
A More Complex Lighting Environment 358
Rendering the Element 372
Getting the Color Perfect Is Not Your Job 372
Chapter 25 Lighting Setup Examples 374
Exterior Sunny Day 374
Exercise 1: Direct Key, Ambient Fill 375
Exercise 2: Direct Key, Direct Fill 380
Exercise 3: Using Shadow Maps 381
Exercise 4: Area Shadows 383
Exercise 5: Using a Skylight for the Fill 384
Exercise 6: mental ray Area Lights 386
Exercise 7: Using Photometric Lights 392
Exercise 8: IES Sun and IES Sky 397
Exterior Scenes with Radiosity 401
Index 403
· · · · Contents
xiii
Trang 15First and foremost, I wish to thank my publisher, Wes Beckwith, for hisendless encouragement, support, and enthusiasm I am grateful for theconfidence he placed in me to complete this project to a high standardand on schedule Thanks to all the other Wordware folks for their contri-butions and efforts on this book, especially Beth Kohler, who trains hereagle eye on the text, eschewing obfuscation at every turn
Secondly, I’d like to thank Marnie Marshall, lighting artist and MAXlighting expert at Electronic Arts in Vancouver, British Columbia, whoread over the manuscript, checking for technical errors and lack ofclarity
I’d like to acknowledge the contributions of Jessica Chambers, nical director at the Shadbolt Centre for the Arts in Burnaby, BritishColumbia, Canada Thanks to Jessica for the use of her head in Chapter
tech-1 and the use of her theater facilities to photograph some of the lightingconcepts I attempt to describe herein
Thanks to Rainmaker’s Brian Moylan, director of digital imaging, forendless support and enthusiasm for the job, for keeping it real, and forencouraging personal projects such as this, which sometimes take timeand focus away from the pressure-cooker of daily production work.Numerous others have contributed in some part to this book Fromhyper-talented lighting designers and college professors back in themists of time to the 3D artists of the world Some of these people I workwith every day and others I know only by reputation, but from all I con-stantly learn new tricks and techniques Every step down the path hasled to this book, and so here it is I hope you enjoy it I hope, especiallythough, that this book brings you some new skill or understanding andhelps improve your lighting in some small way
xiv
Trang 16While reading this book, you will find areas where repetition occurs.Lighting a scene involves the application of numerous tools, methods,and properties that are all interlinked Although I have endeavored toseparate each element into chapters for easy comprehension, they none-theless overlap here and there I found that a small measure of repetition
is preferable to constantly referring the reader to other chapters
Why Write This Book?
I have had the privilege of working with some incredibly talented artists,yet some of them have not grasped the simplest lighting principles Thefinal scene is beautiful to be sure, but many artists run into two mainproblems lighting those scenes One is that while the lighting is perfectand beautiful, it may have taken hours to accomplish through a system oftrial and error The other problem is that the lighting is imperfect, per-haps disobeying the laws of physics It just looks wrong The artist orviewer may not be able to put their finger exactly on the problem, buteven an untrained eye has spent a lifetime experiencing the propertiesand qualities of light You can’t fool the audience Understanding a fewprinciples can solve this problem for the artist
I have a 20-year background in practical lighting for stage and video
My studies derive from those of artists throughout history who havelabored to understand the properties and qualities of light so they mightincorporate those qualities into their own works It seems natural that3D artists should begin from the same point as painters, sculptors, andphotographers, especially since 3D art embodies all three of thesedisciplines
xv
Trang 17Good lighting can make the difference between a good shot and a
great one I would like to see more artists equipped with a strong
enough understanding of lighting to make them masters of their art Tothat end, I wish to share the tidbits of knowledge and experience I haveacquired over the years through my own studies
Why Read This Book?
If you have ever looked at a photograph and been unable to decipher thelight sources, direction, and color, or if you have been unable to replicatethis lighting within MAX, this book will help you If you have ever
thought your lighting looked flat, boring, meaningless, inane, hensible, stale, clichéd (stop me any time), overused, cheesy, CG, fake,
incompre-or derivative, reading this book might be a good move If you have everwondered how to make objects stand out from the background, how to
demonstrate all the minute detail you have spent weeks modeling, or
how to make a shot feel sad, angry, or joyous, you might take some time
to look through these pages If you have seen the work of some great 3Dartists and marveled at how photo-real everything looks and wished youcould add that sense of realism to your work, read on
Good lighting is crucial to the final look of your shot Even a poorlydesigned, marginally textured object can still look like it really exists if
the lighting is good On the other hand, a beautifully designed, ingly modeled and textured object, if lit poorly, will be easily identified ascomputer generated
painstak-Screw Physics!
Physics nitpickers, beware This section may offend some readers
Lighting can be a very contentious issue That is not to say that it isvery complex or difficult to learn It is not But it can be difficult to talk
about This is mainly because there is a certain breed of people who justcan’t let reality go I teach that a shadow may have a certain color based
on a number of different environmental factors Someone nit-picks thatshadows don’t actually have any color, being, themselves, the simple
absence of light (This is technically true, but quite unimportant to CG
lighting.) I teach that certain light types behave a particular way Some
physics snob claims it’s all wrong and lectures me about angstroms,
electromagnetic wavelengths, photons, and wave theory
It comes down to a few simple arguments First,
computer-generated imagery is fake It is therefore not real and subsequently is
not obliged to live by real laws of physics Second, it is unimportant what
Introduction · · · ·
xvi
Trang 18hacks and tricks you had to pull and what physics you had to ignore aslong as things turned out the way you intended and the final renderlooks great Third, did you really purchase this book for a lecture on ang-stroms, electromagnetism, and the behavior of up quarks and downquarks? Or is it the art of computer-generated lighting we’re talkingabout?
Hopefully by the time you have reached this paragraph, you haveeither tossed this book in the bin because you are a nit-picking physicssnob and I have deeply offended your sense of reality (yay!), or you havecome to the conclusion that there will be some “bending” of the laws ofphysics here As a matter of fact, I plan to outright break, smash, andstomp some physics simply to amuse myself Does it matter so long asthe final render looks photo-real? Well, does it?
Physics is important to lighting for a number of reasons, not least ofwhich is that it explains why light and shadow behave the way they do,but it is not there to fetter our artistic endeavors, our tastes, or even ourbaser need to get a render done quickly Let’s face it: If we were con-strained to using lighting tools that only obeyed the laws of physics,frames would take days, weeks, or months to render instead of minutes.Physics helps us understand how real things work so that we knowhow to build tools and techniques that approximate those realities Ofcourse the goal is to approximate them so well that they look completelyphoto-real This approximation is likely to be a big compromise that ismade up of completely impossible tools and techniques, cheats, fakes,hidden truths, and some seriously great compositing work post-renderconsisting of motion blur, film grain, smoke, dust, nasty edge-work,rotoscoping, and probably shaking a live chicken over the tablet aboutfive minutes before delivery deadline
Take lights, for example In the real world, there is only one basiclight type All light sources fall into this one category and can be
described using one set of rules (Argue if you will; I’m not listening.)MAX, on the other hand, is equipped with a number of different lighttypes Each different light is characterized by specific light propertiesthat may or may not exist in real lighting but have been designed tomake your frames render much, much more quickly None of the lightsavailable in MAX behave exactly as real light does Those brainiacs whohave coded our lighting tools have split up various light properties intoseparate lighting instruments and controls, giving us the ability to createlighting looks without having to go through all the hassle of using realphysics to render
For example, in the real world, if you turn up the intensity of a light,the specular highlight and reflection on a surface will also increase That
· · · · Introduction
xvii
Trang 19is because they are all part of the same property In the virtual world,
however, these properties can all be manipulated individually,
com-pletely disobeying the law Shame!
So to begin with, we are going to ignore physics except in our vations of real-world light When it comes to lighting in the virtual
obser-world, we need to understand the laws so we can make something that
appears to work like them, but we do not need to obey them In this way,
we are gods and make our own physical laws Light behaves the way wedesire it to in our virtual worlds because we wish it
There, now don’t you feel like tossing a lightning bolt or something?
Some Notes about Observation
Observation of the real world is the backbone upon which all the rest ofyour artwork, including lighting, rests You will never, ever learn good
lighting, animation, texturing, or much of anything else by simply sitting
in front of a computer monitor clicking keys and scrolling your mouse
wheel If it is your desire to become a truly world-class artist, it is yourobligation to yourself to get out there and study the world that you are
striving to copy
Painters perform many painting and drawing studies before ing a large work If they need to work out just how a human hand lies orjust how cotton fabric crumples, they will draw hands in many differentpositions or they will get cotton and lay it out, drawing it over and overuntil they fully understand its properties and behaviors Lighting is justlike this
attempt-If you expect to create realistic lighting, you absolutely must get outthere and observe lighting conditions See the properties of light and
shadow under as many different environmental conditions as possible
Analyze and study both lighting and shadow Understand how different
textures react to specific lighting conditions Know what a reflection is
before you attempt to alter the reflectivity, specularity, and glossiness of
a texture at the workstation As a lighting artist, it is your duty to reach
a Zen understanding of lighting Be one with the light, young pixel rai, and ye shall reap the rewards
samu-Introduction · · · ·
xviii
Trang 20Rules of the Road
The first rule any artist learns is that there are no rules This book willdemonstrate how light works, how to look at it, and how certain tools inMAX’s toolkit can be used to approximate or replicate it There are also
a number of lighting techniques covered, some of which are commonlyused in film and television These are not rules; they are principles andtechniques Once you understand lighting, you will discover that you donot need rules or techniques described for you, that you can create yourown techniques, that you can make up your own rules Simply put, youcan light a scene any way you wish if it pleases you Your best bet forlearning how to gain complete control over your lights is to experiment,ignore standard practices, and investigate exactly how your lightinginstruments perform and react Anyone who tries to tell you about rules
is mistaken
What is “good lighting”? That’s a loaded question If I had to define
it I would say “good lighting” is what occurs when the results are whatthe artists set out to create I have met directors who believe that “goodlighting” means everything in the scene is brightly lit so you can seeevery detail What if the scene is in a dark alley at night with a couple ofsmall overhead street lamps just barely bright enough to create two dimpools on the asphalt? Should I throw in a nice bright distant light at100% so everything is brightly lit? Of course I shouldn’t This is a prettyobvious example but it demonstrates the point: Good lighting looks andfeels right Believe it or not, you are already an expert on what lightshould look like You’ve been observing the effects and qualities of lightsince you first opened your eyes Trust what your eyes tell you My job
is to dissect and define all those things you already know and presentthem to you in a way that will allow you to manipulate them like old,familiar hand tools
A Note About Art: There is little that can replace a traditional art background You have probably heard or read this a hundred times and rolled your eyes, but it remains fundamentally true It is not about whether you can draw, paint, or sculpt but about learning how to look
at your subject and dissect it into forms, colors, and intersections so they can be recreated on your own canvas, in this case your computer.
If you do not have any art training, do not dismay; this book will still help you improve your lighting I would be remiss, however, if I did not recommend that you take a couple of evenings a week and attend a class at your local arts institute Most community centers have arts classes of some sort If your desire is to become a world-class artist, you really should study art.
All right, enough of that soapbox.
· · · · Introduction
xix
Trang 21Lighting, Both Beautiful and Accurate
Pleasing lighting is not mutually exclusive from accurate lighting
This may seem to be an obvious statement, but you would be
sur-prised how many artists throw lights into a scene to highlight an item
when there is no lighting source to justify the illumination Accuracy is
key to good-looking lighting If you really need to highlight something
and there are no light sources to justify it, there are other steps you cantake to achieve a good look Altering the background is one such solu-
tion, although it’s not always possible Find a way to add a light source tojustify the light you need If nothing else works, at least try to make theoffending effect subtle enough to pass notice
You might even get away with making alterations to the subject or
its textures Creativity is not just about building, painting, and lighting It
is also about finding creative solutions to problems just like this that pop
up every day Part of your job is to fix them
In your career as a lighting artist, you will probably encounter tions where you are ordered to highlight something and denied
situa-permission to make any alterations that will justify that highlight This
especially happens when the budget is tight, time is short, and/or the
director or VFX supervisor is inexperienced This is where the VFX
supervisor has a tough job trying to coordinate between director, gaffer,and CG department to try to make the final composition seamless and
real You should try to argue your point, but sometimes they don’t want
to hear it Just smile, nod, do the work, and don’t put it on your reel
Sometimes you just have to walk away
Note: Some filmmakers are euphemistically referred to as “guerilla
filmmakers.” This evokes a mental image of hurried, hit-and-miss
operations that spawn marginal results or failures If you are very
lucky, you will never end up trying to light shots for these “guerilla”
filmmakers, whose favorite expression at the end of a long day seems
to be “They’ll fix it in post.” Because visual effects shots seem to be left
until the end of the day when everybody is very tired, working
dou-ble-overtime, and anxious to get home, the work is hurried and
sloppy That means it is up to you and the rest of the VFX team to fix
whatever mistakes these filmmakers can’t be bothered to fix
them-selves I have seen some pretty incredible expectations come from set
regarding post fixes.
• A chair is left in frame for a shot Instead of reshooting, the crew
wraps for the day and requires a compositor to paint out the chair.
• A scene is in the can Later the production team decides they don’t
like the round neckline on a dress A compositor is ordered to make
it square.
Introduction · · · ·
xx
Trang 22• Green-screen shots come back with completely improper lighting angles for the CG environment that is to be added by the VFX team Green light spills all over the talent Many hours of roto are required and the lighting must be altered to accommodate the plate.
All of these are due to lack of planning, unrealistic time constraints, and laziness Unfortunately, it adds a massive workload to the VFX department, which would like to be spending its time making the shots world class but instead spends time cleaning up other people’s messes and does not then have enough time to properly finish its own shots.
There are also many filmmakers who plan carefully and who care about the results.
If you are lucky, the shots are carefully planned, the CG department isincluded in the planning process, and the shots come back as expected.What is more likely is that one or all of these events will not occur This
is where your creativity is really going to come into play, where you willreally need to know your lighting to pull off a miracle
You will discover that there are many ways to skin a cat Regardless
of whether the shots you receive are manna from heaven or guerillacrap, you will find that stunning results can be achieved with the slight-est planning
About Trial and Error
Many CG artists rely on trial and error as a prime lighting technique.This is not the same as experimentation Since rendering a frame ishardly real-time feedback, there will be some amount of tweaking andrendering to achieve the right levels, colors, and balance; however, mostaspects of lighting do not, and should not, require trial and error Prop-erties such as instrument choice, position, direction, basic intensity, andcolor should require marginal adjustment, especially in visual effectsshots where these properties have already been established by the filmcrew or where visual references are available in the plate and your job issimply to recreate the lighting environment The VFX artist should beable to look at a plate; identify exactly how many light sources there are;identify roughly their position, direction, and colors and what light typesare required; plan out a lighting kit; and then proceed with placement.Designing your own lighting is a slightly different matter and mayrequire more experimentation, especially considering this may be part ofthe creative process for some artists This process, however, should not
be mistaken for “trial and error.” Trial and error is best illustrated by theartist who does not know what he wants, does not know exactly how toachieve it, and adds lights, colors, direction, and intensity in the hopesthat sooner or later he will accidentally hit on a pleasing combination
· · · · Introduction
xxi