The Foundry Nuke 101 Manual

Nuke 101

Professional Compositing and Visual Effects

Ron Ganbar

Peachpit Press

1249 Eighth Street

Berkeley, CA 94710

510/524-2178

Fax: 510/524-2221

Find us on the Web at www.peachpit.com

To report errors, please send a note to [email protected]

Peachpit Press is a division of Pearson Education

Copyright © 2011 by Ron Ganbar

Senior Editor: Karyn Johnson

Development Editor: Corbin Collins

Production Editor: Cory Borman

Technical Editor: Mark Christiansen

Copyeditor: Kelly Kordes Anton

Proofreader: Scout Festa

Indexer: Valerie Haynes Perry

Interior Design and Composition: Kim Scott, Bumpy Design

Cover Design: Charlene Charles-Will

Cover Illustration: Alicia Buelow

Cover images: Adrenalin Lemmings (2008) by Crew 972, www.crew972.com

Notice of Rights

All rights reserved. No part of this book may be reproduced or transmitted in any form by any means, electronic, mechanical, photocopying, recording, or otherwise, without the prior written permission of the publisher. For information on getting permission for reprints and excerpts, contact [email protected].

Footage from Adrenalin Lemmings used with permission from Crew 972. © 2008 Crew 972, www.crew972.com. All rights reserved.

Footage from “This is Christmas,” directed by Alex Norris, www.alexnorris.co.uk

Keying footage (Chapter 7) by Hector Berebi, http://prepost-consulting.blogspot.com/

Pan and Tile panorama footage (Chapter 10) by Assaf Evron, www.assafevron.com/

Notice of Liability

The information in this book is distributed on an “As Is” basis without warranty. While every precaution has been taken in the preparation of the book, neither the author nor Peachpit shall have any liability to any person or entity with respect to any loss or damage caused or alleged to be caused directly or indirectly by the instructions contained in this book or by the computer software and hardware products described in it.

Trademarks

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ISBN-13: 978-0-321-73347-4

ISBN-10: 0-321-73347-9

9 8 7 6 5 4 3 2 1

Printed and bound in the United States of America

This page intentionally left blank

“I don’t always like writing, but I very much like having written.”

—William Gibson

CONTENTS

Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ix

ChaPTER 1:

Getting Started with Nuke . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1

Components of the Graphic User Interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2

The Content menu . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3

A rundown of the various panels . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3

The menu bar . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4

The contextual menu. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6

Hot keys . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6

Nodes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

Creating a node . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

The Read node . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9

The File Browser . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9

The Viewer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11

Navigating the Viewer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12

Using the Viewer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13

Viewer inputs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14

Playing a clip in the Viewer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15

Framecycler . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16

ChaPTER 2:

Touring the Interface with a Basic Composite . . . . . . . . . . . . . 19

Working with Process Trees . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20

Creating a Simple Process Tree . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22

Merging Images . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .24

Merging premultiplied images . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26

Saving Nuke scripts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29

Inserting and Manipulating Nodes in the Tree . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30

Inserting, creating, branching, and replacing nodes . . . . . . . . . . . . . . . . . . . . . 30

Connecting nodes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .32

Selecting nodes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .33

Arranging nodes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .34

Disabling and deleting nodes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .34

Changing Properties . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35

Color correcting the image . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36

Using the Properties Bin. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .37

Adjusting properties, knobs, and sliders . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38

Using the Color Wheel and Color Sliders panel . . . . . . . . . . . . . . . . . . . . . . . . . 40

Using the Animation menu . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41

Rendering . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .42

Using the Write node. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .42

Naming file sequences . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .43

Delving Deeper into the Merge Node . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .47

Using the Shuffle node . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50

Viewing a composite without rendering . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51

Creating Animation with Keyframes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52

Indicators on nodes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 56

Rendering a new version and comparing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .57

Comparing images . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58

ChaPTER 3:

Compositing CGI with Bigger Node Trees . . . . . . . . . . . . . . . . 61

Working with Channels . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 62

Bringing in a 3D render . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63

Viewing channel sets with the Viewer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63

Working with Contact Sheets . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65

Using the Bounding Box to Speed Up Processing . . . . . . . . . . . . . . . . . . . . . . . . . . . 66

Linking Properties with Expressions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69

Slapping Things Together: Foreground over Background . . . . . . . . . . . . . . . . . . . . 71

Building the Beauty Pass . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .73

Working down the pipe . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .73

Splitting the tree . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .76

Using the ShuffleCopy Node . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 84

Manipulating Passes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 85

Adding other CGI Images . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .87

Placing CGI over Live Background . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 91

Using the Mask Input . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 93

ChaPTER 4: Color Correction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 97

Understanding Nuke’s Approach to Color . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 98

Color Manipulation Building Blocks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 99

Dynamic range . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .100

Using an I/o Graph to Visualize Color operations . . . . . . . . . . . . . . . . . . . . . . . . . . .105

Creating Curves with ColorLookup . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .111

Color Matching with the Grade Node . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 113

Using the Grade node . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 113

Using CurveTool to match black and white points . . . . . . . . . . . . . . . . . . . . . . . 118

Matching midtones by eye . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .122

CoNTENTS

v

vi

NUKE 101

Achieving a “Look” with the ColorCorrect Node . . . . . . . . . . . . . . . . . . . . . . . . . . . .125

Using the ColorCorrect node . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .125

Using the mask input to color correct a portion of the image . . . . . . . . . . . . . 131

ChaPTER 5:

2D Tracking . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 135

Tracker Node Basics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .136

Stabilizing a Shot . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 137

Tracking Four Points . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 143

Understanding tracking points . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 143

Tracking a picture in the frame . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .144

Changing the Tracker settings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .146

Replacing the picture . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .148

Adjusting the source pins . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .152

Adding motion blur . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .154

ChaPTER 6: RotoPaint . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 159

Introducing RotoPaint’s Interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .160

Painting strokes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .162

Editing strokes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .163

Painting in vectors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .164

Erasing and deleting strokes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .165

Drawing and editing shapes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .166

Animating a shape . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .168

The Curve Editor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 170

Painting in Practice . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 174

Using Paint for wire removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 175

Dust removal with Paint . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 176

Split-Screening Twins with Roto . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 178

Combining Paint, Roto, and Animation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .185

Compositing with the KeyMix node . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 187

Working with the Stroke/Shape List window . . . . . . . . . . . . . . . . . . . . . . . . . . . .188

Using the Dope Sheet . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 191

ChaPTER 7: Keying . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 197

Introducing Nuke’s Keying Nodes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .199

HueKeyer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .201

The IBK: Image Based Keyer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 203

Keylight . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .210

Combining Keyer Nodes Using the Tree . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .216

Erode, Dilate, and Erode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 217

Spill suppressing with HueCorrect . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 220

ChaPTER 8:

Compositing hi-Res Stereo Images . . . . . . . . . . . . . . . . . . . . .225

Using the Project Settings Panel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 226

The Root tab . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 226

Nonlinear images and lookup tables (LUTs) . . . . . . . . . . . . . . . . . . . . . . . . . . . 227

The Views tab . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 229

Setting Up a High-Res Stereo Script . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 230

Setting formats . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .231

Working with LUTs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 233

Stereo views . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 235

Using proxies . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 238

Creating stereo-view proxies efficiently . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 243

Compositing a Stereo Project . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 246

Retiming elements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 246

Compositing the two elements together . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 249

Changing properties for a single view . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 251

Rendering and Viewing Stereo Trees . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 253

ChaPTER 9: The Nuke 3D Engine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .257

3D Scene Setups . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 258

Moving Images with a 3D Scene . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 259

Setting up a Nuke 3D scene . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 259

Navigating the 3D world . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .261

Importing a camera . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 263

Creating a cube . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 265

Reconcile3D: Transforming 3D Data into 2D Data . . . . . . . . . . . . . . . . . . . . . . . . . . 268

Setting up a Reconcile3D node . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 268

Using Reconcile3D’s output with a Tracker node. . . . . . . . . . . . . . . . . . . . . . . 273

Final Disclosure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 277

ChaPTER 10:

Camera Tracking . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .279

Calculating Reflection Movement Using Camera Tracking . . . . . . . . . . . . . . . . . . 280

3D Tracking in Nuke . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .281

Tracking features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 282

Solving the camera . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 284

Creating the scene. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 286

Loading a Pre-Generated CameraTracker Node . . . . . . . . . . . . . . . . . . . . . . . . . . . 287

Aligning the Scene . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 287

Creating the Reflection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 292

ScanlineRender nodes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 293

Creating the reflective surface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 296

Environment light and specular material . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 298

Cutting the reflection to size . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 302

CoNTENTS

vii

viii

nuke 101

chapter 11: camera projection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 305

Building a Camera Projection Scene . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 306

Tweaking the Geometry . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .315

Animating the Camera . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .316

Tweaking the Texture . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .318

using a SphericalTransform to Replace Sky . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 320

Compositing Outside the ScanlineRender node . . . . . . . . . . . . . . . . . . . . . . . . . . . 323

Cloning nodes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 323

Final adjustments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 325

2D Compositing Inside 3D Scenes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 326

Importing Photoshop layers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 326

Creating the frame . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 332

Compositing the screen into the 3D scene . . . . . . . . . . . . . . . . . . . . . . . . . . . . 334

Rendering the Scene . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 336

chapter 12: customizing Nuke with Gizmos . . . . . . . . . . . . . . . . . . . . . . .337

About Safety Areas . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 338

Building the Gizmo’s Tree . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 339

Creating user knobs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 342

Scripting with a Little TCL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 348

Testing the Gizmo’s Tree . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 352

Wrapping in Groups . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 353

Manipulating the nuke Script in a Text editor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 359

Turning a Group into a Gizmo . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 362

Installing the Gizmo . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 363

Testing the Gizmo . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 363 using the Viewer Input Process . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 364

More About Gizmos . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 365

appeNdix i: customizing Nuke with python . . . . . . . . . . . . . . . . . . . . . . . .367

Python Scripting Basics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 368

Creating a Button with Python . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 369

Adding a Hot key . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 371

Making Customization Stick with the Menu .py File . . . . . . . . . . . . . . . . . . . . . . . . . 372

Creating and adding an icon . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 372

Other uses for menu .py . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 375

index . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .377

See last page of this eBook for instructions on downloading your lesson files .

INTRODUCTION

The Foundry’s Nuke is fast becoming the industry leader in compositing software for film and TV. Virtually all the leading visual effects studios—ILM, Digital Domain, Weta

Digital, MPC, Framestore, The Mill, and Sony Pictures Imageworks—now use Nuke as their main compositing tool. This is not surprising, as Nuke offers a flexible nodebased approach to compositing, has a native multi-channel workflow, and boasts a powerful integrated 3D compositing environment that delivers on the artist’s needs.

Nuke was first developed as the in-house compositing tool at Digital Domain, the visual effects studio behind the Terminator series, The Fifth Element, Tron: Legacy,

The Curious Case of Benjamin Button , and other major films. The software has been developed by artists for artists to meet the immediate needs of actual top-level productions. Nuke is now developed by The Foundry (www.thefoundry.co.uk), which remains committed to making Nuke the best tool for compositing artists working in the trenches.

AbouT This book

Learning Nuke is a must for visual effects artists who want to master high-end compositing techniques and artistry. My goal with this book is to get you up-and-running with the program and give you the skills you need for doing your own compositing projects in Nuke.

Who this book is for

This book is for anyone interested in learning Nuke. Whether you’re an artist experienced in using Adobe After Effects, Autodesk Flame, Apple Shake, or Eyeon Fusion, or you only have a basic understanding of compositing and image manipulation concepts, this book will guide you through the necessary theory and practice you need to use Nuke—from a basic level to Nuke’s more advanced toolset.

how this book is organized

This book was written as a series of lessons, each focusing on a part of the interface, a tool, or a technique. Chapters 1 through 3 discuss Nuke basics, which are important for understanding where things are and how to create simple composites. Chapters 4 through 7 cover important tools and techniques. In Chapter 8 and onwards, advanced tools and techniques are explained.

x

NUKE 101

What this book covers

This book teaches how to use Nuke from its very basic interface to its very advanced toolsets, including the 3D engine, Camera Projection, and Camera Tracking. Although the book teaches a fair amount of compositing theory, there is not enough space here to cover that topic in depth. Some of the theory discussed in this book may be new to you, but my intention is to cover just enough to understand how to use

Nuke. If you want to dive further into the theory, two of my favorite books are Ron

Brinkmann’s The Art and Science of Digital Compositing and Steve Wright’s Digital

Compositing for Film and Video .

how to use this book

As you advance through the chapters in this book, the later lessons rely on knowledge you learned in the previous lessons. Chapter 2 relies on what you learned in

Chapter 1, and so on. Because of this, I recommend completing the exercises in the chapters in order.

In the book you will find explanatory text and numbered steps. Ideally, you should complete each numbered step exactly as it is written—without doing anything else

(such as adding your own steps). Following the steps exactly as written will give you a smooth experience. Not going through the steps as they are written might result in the next step not working properly, and could well lead to a frustrating experience.

Each series of steps is also designed to introduce you to new concepts and techniques. As you perform the steps, pay attention to why you are clicking where you are clicking and doing what you are doing, as that will truly make your experience a worthwhile one.

You can use this book on your own through self-study or in a classroom.

n

Using the book for self-study: If you’re reading this book at your own pace, fol-

low the instructions in the previous paragraph for your first read-through of the chapters. However, as you are not limited by any time frame, I recommend going through chapters a second time, trying to do as much of the work without reading the steps. Doing so can help you better understand the concepts and tools being taught. Also, the book leaves a lot of room for further experimentation. Feel free to use the tools you’re learning to take your compositions further the second time you run through a chapter.

n

Using the book in a classroom setting: You can use this book to teach Nuke in

a classroom. As a course, the material is designed to run for roughly 40 hours, or five eight-hour days. I suggest the trainer run through a chapter with the students listening and writing down notes, explaining the steps as they are shown on-screen to the class while taking questions and expanding on the text where

necessary. once a chapter has been presented from start to finish, give students time to run through the same chapter on their own in the classroom in front of a computer, using the book to read the instructions and follow the steps. This second pass will reiterate everything the trainer has explained and, through actual experience, show the students how to use the software with the trainer still there to answer questions and help when things go wrong.

iNsTALLiNg Nuke

While this book was originally written for Nuke version 6.2v1, The Foundry updates

Nuke on a regular basis and the lessons can be followed using more recent updates.

Small interface and behavior updates might slightly alter the Nuke interface from version to version, especially for so-called “point” updates (such as if Nuke version 6.3 were released). I recommend using this book with Nuke version 6.2v1 if you haven’t already downloaded the most current version and you want the exact results as shown in the book.

You can download Nuke in a variety of versions from The Foundry’s web site at www.thefoundry.co.uk as discussed in the next sections.

Different flavors of Nuke

Nuke comes in three different flavors with different features at different prices. There is only a single installation file for Nuke, but the license you purchase determines which type of Nuke you will be running. The Foundry offers a 15-day trial license, so you can try it before you purchase it (see “Getting a trial license” later in this section).

Here are the three flavors of Nuke.

1 .

Nuke PLE (Personal Learning Edition): This license (or lack of) is free—as in, you

pay nothing. You can install Nuke on your computer and not purchase a license.

With the PLE you can use Nuke as much as you want, although certain limitations apply. These include the placement of a watermark on the Viewer and on renders, and the disabling of WriteGeo, Primatte, Framecycler, and Monitor output.

2 .

Nuke: This is regular Nuke—the flavor this book covers. Nuke requires a trial

license or regular paid license, which should cost about $4,500.

3 .

Nukex: This license includes all the regular Nuke features with a few additional

high-end tools. These tools include the CameraTracker, PointCloudGenerator,

LensDistortion, DepthGenerator, Modeler, FurnaceCore plug-ins, and PRman-

Render (allowing for Renderman integration). NukeX costs in the region of

$7,000. Chapter 10 covers the Camera Tracker and shows how to use it under the NukeX license; however, the exercises in the chapter can also be done without a NukeX license.

INTRoDUCTIoN

xi

xii

NUKE 101

Downloading Nuke

To download Nuke, follow these steps.

1 .

Go to www.thefoundry.co.uk/products/nuke/product-downloads/.

2 .

Select the latest copy of Nuke for your operating system (Mac, Windows, or

Linux). You can also download older versions of Nuke if necessary.

3 .

If you’re downloading the latest version, you need to register and then you are directed to the download page. (Downloading older versions from the archive does not require registration.)

4 .

Follow the instructions for installation on your specific operating system.

getting a trial license

After successfully installing Nuke, when you double-click the Nuke icon it explains that because you don’t have a license yet, you can use Nuke under the PLE license. If you would like to use a fully licensed Nuke or NukeX, you will have to buy Nuke, rent

Nuke (both available on the Foundry’s web site shown below), or get a free 15-day trial license.

As there is no functional difference between getting a Nuke trial license or a NukeX trial license, I recommend getting a NukeX trial license. To get your free 15-day trial

NukeX license, do the following:

1 .

Go to www.thefoundry.co.uk/products/nuke/try/.

2 .

Log in or sign up to get to the Free Trial page.

3 .

In the Free Trial page, fill in the form.

The System ID, which is the first entry to fill, is the unique code of your computer—the free license will be locked to that computer. The link to the right of the entry field explains where to find this number on your computer.

4 .

After you complete the form and click Continue, follow the rest of the instructions on the Foundry’s web site for how to install the license on your operating system.

staying up to date

Because Nuke is updated often, please visit the web site at www.peachpit.com/ nuke101 for periodic updates to the book. I will strive to publish notes about behavior in new versions of Nuke as they come out if they differ from what’s written in the book.

Also, I will periodically publish additional information and more tutorials on the web site that will add further content to the book.

ADDiTioNAL TechNicAL RequiRemeNTs

Nuke is a very powerful piece of software, even though its system requirements are pretty low. If you bought your computer in the last couple of years, you are probably oK. The requirements are listed on The Foundry web site but there are three things you should really check: n

Workstation-class graphics card, such as NVIDIA Quadro series, ATI FireGL series, R3D Rocket, or newer. Driver support for openGL 2.0.

n

Display with at least 1280x1024 pixel resolution and 24-bit color.

n

Three-button mouse. This kind of mouse is really a must as Nuke uses the middle mouse button extensively. A scroll wheel, by the way, can serve as the middle mouse button.

To copy the exercise files to your computer, you will need a DVD drive as well.

For a full list of Nuke’s system requirements, visit www.thefoundry.co.uk/products/ nuke/system-requirements.

AbouT The book’s Disc FiLes

At the back of the book you will find a DVD-RoM disc containing the files you need to complete the exercises in this book (or if you bought the ebook version, you’ll be presented with a link to the files). The files are a mix of a real production that I or my colleagues created in recent years and some shot elements intended for use with this specific book.

What’s on the disc

Each chapter has its own directory. Copy these directories to your hard drive to use the files properly. Some chapters use files from other chapters, so you need to copy all the directories to your hard drive.

how to install the files

1 .

Insert the Nuke101 DVD into your DVD drive.

2 .

Create a directory on your hard drive and name it

NukeChapters.

3 .

Drag the chapters directory from the DVD into the NukeChapters directory on your hard drive.

INTRoDUCTIoN

xiii

xiv

NUKE 101

AckNoWLeDgmeNTs

I’ve been teaching compositing since 2001. When Nuke started becoming the tool of choice for a lot of the studios around me, I decided to write a course that focused on it. I started writing the course in the spring of 2009 with help from The Foundry, whose staff was very kind and forthcoming. I would specifically like to thank Vikki

Hamilton, Ben Minall, Lucy Cooper, and Matt Plec.

I finished writing the original course around the autumn of 2009. I taught it several times at Soho Editors Training in London, which was kind enough to let me try out the new course at their training facility. The course was well received, so between sessions I updated, corrected, and expanded on the original course.

About a year after that I approached Peachpit Press with the idea of turning the course into a book. Karyn Johnson, the book’s senior editor, took on the project and after a long digestion period I sat down and started adapting the course into a book.

Karyn made sure I had the best support I could possibly have, and with the help of the wonderful team at Peachpit, including Corbin Collins and Kelly Kordes Anton, I managed to complete the book to the high standard Peachpit expects of their writers. Thanks also go out to the kind friends and colleagues who gave me materials to use for the book: Alex orrelle, Alex Norris, Hector Berrebi, Dror Revach, Assaf Evron,

Menashe Morobuse, and Michal Boico.

It was quite a ride. You can see it took me three paragraphs to cover it all. But throughout this long period, which sometimes felt like it would last forever, my wife,

Maya, and my two sons had to bear with my long days and long nights of writing, gave me the quiet and solitude I needed, and believed (and prayed) that I would finish the book. And so I have.

In so many ways, this book is for them.

Throughout this title you will see references to lesson or resource files on a disc. Please note that these files are available to eBook readers via high-speed download. Please

click here

to go to last page in this eBook for the download location and instructions.

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COLOR CORRECTION

4

Wow. This is a bit naive. Calling a lesson “Color Correction.” it should be a whole course on its own. But this book is about more than that, and limited space reduces color correction to a chapter. So let me start by explaining what color correction means.

Color correction is one of the most fundamental things you can do to an image. it refers to any change to the perceived color of an image.

Making an image lighter, more saturated, changing the contrast, making it bluer—all of this is color correction. There are a lot of uses for color correction. The most obvious one is to make an image look different as a result of a stylistic decision. But you can also color correct to combine two images so they feel like part of the same scene. This is performed often in compositing when the foreground and the background should have colors that work well together. There are plenty

98

NUKE 101 more uses for changing the color of an image. An image might be a mask or an alpha channel that needs to have a different color in some way—to lose softness and give it more contrast, for example.

Whatever reason you have for color correcting an image, the color correction will work according to the way Nuke handles color. Nuke is a very advanced system that uses cutting-edge technology and theory to work with color. It is important to understand Nuke’s approach to color to understand color correcting within Nuke.

uNDeRsTANDiNg Nuke’s AppRoAch To coLoR

Nuke is a 32-bit float linear color compositing application. A bit of a fancy description there, with potentially new words. I explain this bit by bit: n

32-bit : That’s the amount of bits used to hold colors. Most compositing and image-manipulation programs are 8-bit, allowing for 256 variations of color per channel (resulting in what’s referred to as “million of colors” when combining the three color channels). This is normally fine for displaying color, but is not good enough for some calculations of operations, and may result in unwanted results such as banding—inaccurate display of gradients where changes in color happen abruptly instead of smoothly. 32-bit allows for a whopping 4,294,967,296 variations of color per channel. That’s a staggering amount that results in much more accurate display of images and calculations of operations. 8- or 16-bit images brought into Nuke will be bumped up to 32-bit, although that doesn’t add any detail, it just enables better calculations from that point onwards.

n

Float: Normally the color of an image is represented between black and white.

In 8-bit images, for example, the 256 color variations are split evenly between black and white—so the value 1 is black, the value 256 is white, and the value 128 is a middle gray. But what about colors that are brighter than white? Surely the whiteness in the middle of a lit light bulb is brighter than a white piece of paper?

For that reason, there are colors that are brighter than white called super-whites.

There are also colors that are darker than black called sub-blacks (but there isn’t a real-world analogy that can be used here short of black holes). Using 8 bits to describe an image simply doesn’t allow enough room to describe colors beyond black and white. These colors get clipped and are simply represented as black or white. However, in 32-bit color, there is plenty of room and these colors become representable. As mentioned before, 8-bit color is normally enough to display images on-screen. Furthermore, the computer monitor can still display only white—and nothing brighter. However it is still very important to have access to those colors beyond white, especially when color correcting. Darkening an image that has both a piece of white paper and a light bulb in it will leave the light bulb white, while darkening the paper to a gray color results in an image that mimics

CoLoR CoRRECTIoN

99

n real-world behavior and looks good and believable. Doing the same with a nonfloating image will result in the white paper and the light bulb looking the same gray color—which will be unconvincing.

Linear: Linear can mean lots of things. In terms of color, I mean linear color space.

A computer monitor doesn’t show an image as the image appears in reality, because the monitor is not a linear display device. It has a mathematical curve called gamma that it uses to display images. Different monitors can have different curves, but most often they have a gamma curve called sRGB. Because the monitor is not showing the image as it appears in reality, images need to be “corrected” for this. This is usually done automatically because most image capture devices are applying an sRGB curve too, in the opposite direction. Displaying a middle gray pixel on a monitor only shows you middle gray as it’s being affected by the gamma curve. Because your scanner, camera, and image processing applications all know this, they color correct by applying the reverse gamma curve on this gray pixel that negates the monitor’s effect. This process represents basic color management . However, if your image’s middle gray value isn’t middle gray because a gamma curve has been applied to it, it will react differently to color correction and might produce odd results. Most applications work in this way, and most people dealing with color have become accustomed to this. This is primarily because computer graphics is a relatively new industry that relies on computers that, until recently, were very slow. The correct way to manipulate imagery—in whatever way—is before the gamma curve has been applied to an image. The correct way is to take a linear image, color correct it, composite it, transform it, and then apply a reverse gamma curve to the image to view it correctly (as the monitor is applying gamma correction as well and negating the correction you just applied). Luckily, this is how Nuke works by default.

Still confused? Here’s a recap: Nuke creates very accurate representations of color and can store colors that are brighter than white and darker than black. It also calculates all the compositing operations in linear color space, resulting in more realistic and more mathematically correct results.

Nuke has many color correction nodes, but they are all built out of basic mathematical building blocks, which are the same in every software application. The next section looks at those building blocks.

coLoR mANipuLATioN buiLDiNg bLocks

Color correction is a somewhat intuitive process. often compositors just try something until they get it right. Understanding the math behind color correction can help you pick the right tool for the job when attempting to reach a specific result—which is better than trial and error.

TABLE 4.1

explains most of these building blocks.

Note

Nuke color values are displayed and are calculated in what’s called “normalized values.” This means that instead of defining black at a value of 0 and white at a value of 255, black is still 0, but white is 1.

It’s a very easy thing to remember that makes understanding the math easier.

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NUKE 101

TaBLE 4 .1 Basic Color Correction Functions

Math function

Add

Node

Add, Grade, ColorCorrect

Multiply Multiply, Grade,

ColorCorrect

Explanation

Adds a constant value to a channel.

Multiplies the channel by a constant value.

Gamma

Contrast

Lift

Lookup

Saturation

Names in

Nuke

Add, offset

Other known names

Gain, Multiply Brightness, Contrast,

Exposure, Input/output

White

Gamma, Grade,

ColorCorrect

RolloffContrast,

ColorCorrect

Grade

ColorLookup

Adjusts the color intensity by reducing the differences between the RGB channels.

Applies a gamma curve to a channel.

Applies a contrast curve to a channel. This is also a form of multiplication.

This function is similar to

Multiply and Contrast. It’s a contrast curve with a center at white. More below.

Applies a user-defined curve to a channel.

Saturation

Gamma

Contrast,

RolloffContrast

Lift

ColorLookup

Pedestal, Input/output

Black

Curves

Dynamic range

When dealing with color correction, I usually talk about dynamic range and its parts.

Dynamic range means all the colors that exist in your image, from the darkest to the brightest color. The dynamic range changes from image to image, but usually you are working with an image that has black and white and everything in between. The parts of the dynamic range, as mentioned, are split according to their brightness value as follows: n

The shadows or lowlights, meaning the darkest colors in the image n

The midtones, meaning the colors in the image that are neither dark nor bright n

The highlights, meaning the brightest colors

In Nuke, and in other applications that support colors beyond white and black (float), there are two more potential parts to the dynamic range: the super-whites, or colors that are brighter than white, and the sub-blacks, colors that are darker than black.

Let’s look at these building blocks in several scenarios to really understand what they do and why you might choose one over another.

1 .

Launch Nuke.

2 .

Bring in a clip called Car.png by pressing R and navigating to the chapter04 directory.

3 .

Click Read1, then press 1 on the keyboard to view it.

It’s an image of a car. Did that catch you by surprise?

4 .

With Read1 selected, go to the Color toolbox and click Add in the Math folder.

You have now inserted a basic color-correcting node after the car image. Let’s use it to change the color of the image and see its effect.

5 .

In Add1’s Properties panel, click the Color Picker button to display the Color

Wheel and Color Sliders panel. Play with the R, G, and B colors to see the changes (

FigUrE 4.1

).

FIGURE 4 .1 Using the

Color Wheel and Color

Sliders panel.

CoLoR CoRRECTIoN

101

You can see everything changes when playing with an Add node—the highlights, midtones, and even blacks (

FigUrE 4.2

). An Add operation adds color to everything uniformly—the whole dynamic range. Every part of the image gets brighter or darker.

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NUKE 101

FIGURE 4 .2 The whole image is becoming brighter.

6 .

When you’re finished, close the Color Wheel and Color Sliders panel.

7 .

Select Read1 again and branch out by holding the Shift key and clicking a Multiply node from the Math folder in the Color toolbox.

8 .

While Multiply1 is selected, press 1 on the keyboard to view it.

9 .

In Multiply1’s Properties panel, click the Color Picker button to display the Color

Wheel and Color Sliders panel and experiment with the colors (

FigUrE 4.3

).

FIGURE 4 .3 The changes affect the highlights more than the rest of the image.

You can see very different results here. The highlights get a strong boost very quickly while the blacks are virtually untouched.

10 .

Repeat the above process for the Gamma node. Remember to branch from Read1

(

FigUrE 4.4

).

You can see that gamma mainly deals with midtones. The bright areas remain untouched and so do the dark areas.

FIGURE 4 .4 The midtones change the most when changing gamma.

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You should now have three different, basic, math-based color correctors in your

Node Graph that produce three very different results as shown in

FigUrE 4.5

.

FIGURE 4 .5 The results from changing Add, Multiply, and gamma.

Your DAG should look a little like

FigUrE 4.6

.

FIGURE 4 .6 Branching three color correctors from a node.

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Let’s try some more color correction nodes.

11 .

Select Read1 and then Shift-click RolloffContrast in the Color toolbox to create another branch.

I find it really annoying that they chose to call the Contrast node RolloffContrast, especially since it makes opening it via the Tab key so much harder because typing “contrast” won’t display this node.

12 .

While viewing RolloffContrast1, open its Properties panel and play with the Contrast value (

FigUrE 4.7

).

FIGURE 4 .7 A high

Contrast value produces a high-contrast image.

You can see how, when increasing the contrast above 1, the lowlights get pushed down and the highlights are pushed up.

13 .

Keep the Contrast property above 1 and bring the Center value down to 0.

The Center property changed what is considered to be the highlight or lowlight.

Colors above the Center value will be considered bright and pushed up, and colors below the Center value will be considered dark and pushed down.

You can see the result of the RolloffContrast operation now is very similar to that of the Multiply node. In fact, they are virtually the same. When setting the center value at 0, you lock that value in place. The value 0 is locked in place when multiplying as well.

14 .

Bring the Center value up to 1.

You haven’t gone through an operation called Lift yet, but the RolloffContrast operation is virtually the same as that operation. With Lift, the value 1 is locked in place and the farther the values are away from 1, the bigger the effect. You will go through Lift when you learn about the Grade node later in this chapter.

To wrap up this part of the color introduction, here’s an overall explanation: n

When dealing with color, there’s usually a need to control the lowlights, midtones, and highlights separately.

n

The Add operation adds the same amount of color to every part of the dynamic range.

n

The Multiply operation multiplies the dynamic range by a value. This means that a perfect black doesn’t change, lowlights are barely touched, midtones are affected by some degree, and highlights are affected the most. It is good to mention that a Multiply operation is virtually the same as changing the exposure in a camera or increasing light. It is the most commonly used color operation.

n

The Gamma control is a specific curve designed to manipulate the part of the dynamic range between 0 and 1 (black and white, remember?), without touching

0 or 1.

n

Contrast is actually very similar to Multiply, but has a center control. If you place the center point at 0 you get a Multiply node.

usiNg AN i/o gRAph To

VisuALize coLoR opeRATioNs

And I/O graph (input versus output graph) is a great way to understand color operations. The X axis represents the color coming in, and the Y axis represents the color going out. A perfectly diagonal line therefore represents no color correction. The graph shows what the color operation is doing and the changes to the dynamic range.

To view an I/o graph like this, you can bring in a pre-made script I made.

1 .

Choose File > Import Script to load another script from the disk and merge it with the script you have been building.

2 .

In the File Browser that opens, navigate to chapter04 and click Io_graph.nk to import it into your current script.

Notice that when you imported the script (which is only four nodes) all of its nodes were selected. This is very convenient as you can immediately move the newly imported tree to a suitable place in your Node Graph.

3 .

Make sure the imported tree is not sitting on top of your existing tree. Move it aside to somewhere suitable as in

FigUrE 4.8

.

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NUKE 101

FIGURE 4 .8 You now have two trees in your

DAg.

4 .

Make sure you are viewing the output of Expression1.

A quick explanation of the script you imported, node by node: n

The first node is a Reformat node, which defines the resolution of your image.

In this case, 256x256. Notice that its input isn’t connected to anything. This is a good way to set a resolution for your tree.

n

The second node is a Ramp. This can be created from the Draw toolbox. This node generates ramps—in this case, a black to white horizontal ramp from edge to edge.

n

The third node is a Backdrop node, used to highlight areas in the tree. You can find it in the toolbox called other. It indicates where to add your color correction nodes in the next step.

n

The fourth and last node is an Expression node. This is a very powerful node.

It can be found in the Color > Math toolbox. It lets the user write an expression with which to draw an image. You can do a lot of things with this node, from simple color operations (such as adding or multiplying, though this is wasteful) to complex warps or redrawing of different kinds of images all together. In this case, you use this node to draw values of a horizontal black to white ramp (you have the ramp from above) on-screen as white pixels in the corresponding height in the image. A value of 0.5 in the ramp will generate a white pixel halfway up the Y resolution in the output of the Expression node. The left-most pixel is black in the ramp, and shows as a white pixel at the bottom of your screen. The middle pixel is a value of 0.5 and so shows as a white pixel in the middle of the screen. The rightmost pixel is a value of 1 and so draws a white pixel at the top of the screen. All these white pixels together form a diagonal line (

FigUrE 4.9

). Changing the color of the ramp will change the line. This happens on each of the three color channels individually.

FIGURE 4 .9 The i/O graph at its default state.

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Let’s start using this I/o Graph tree. You will insert a Color node in between Ramp1 and Expression1 and look at the resulting I/o graph.

5 .

Insert an Add node from the Color > Math toolbox after Ramp1 as shown in

FigUrE 4.10

.

6 .

Bring the value of Add2’s value property to around 0.1.

You can see, as in

FigUrE 4.11

, that the Add operation changes the whole dynamic range of your graph, and therefore, for any image.

FIGURE 4 .11 The whole graph is raised or lowered in unison.

FIGURE 4 .10 Add2 has been inserted after ramp1 and will change your i/O graph.

Let’s replace your Add node with a Multiply node. You’ve never done this before, so pay attention.

7 .

With Add2 selected, Ctrl/Cmd-click the Multiply node in the Color > Math toolbox to replace the selected node with the newly created one.

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NUKE 101

8 .

Increase and decrease Multiply2’s value.

9 .

You can also click the color wheel and change the RGB channels individually

(

FigUrE 4.12

).

The Multiply operation has more effect on the highlights than the lowlights. You can see when you are moving the slider that the 0 point stays put, and the further away you go from 0 the effect becomes stronger.

FIGURE 4 .12 The graph changes more the further away it is from 0.

Let’s try Gamma. Maybe you don’t know what a Gamma curve looks like. Well, here’s your chance.

10 .

Replace Multiply2 with a Gamma node from the Color or Math toolbox by holding down Ctrl/Cmd and clicking Gamma from the Color > Math toolbox.

11 .

Load Gamma2’s Color Wheel and Color Sliders panel and play with the sliders for

R, G, and B.

You should now get a similar result to

FigUrE 4.13

.

FIGURE 4 .13 Notice that only the middle part of the graph moves.

The Gamma operation changes the midtones without changing the blacks or whites. You can tell that the point at the furthest left and at the furthest right are not moving.

Contrast is next.

12 .

Replace Gamma2 with a RolloffContrast node in the Color toolbox.

13 .

Bring RolloffContrast2’s contrast value to 1.5.

The contrast operation pushes the two parts of the dynamic range away from one another (

FigUrE 4.14

).

FIGURE 4 .14 A basic contrast curve.

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14 .

Play around with RolloffContrast2’s Center property. When you are finished, set the value to 0.

Here you can see what actually happens when you play with the Center slider.

It moves the point that defines where the lowlights and highlights are. When leaving the center at 1, you can see that the curve is identical to a Multiply curve

(

FigUrE 4.15

).

FIGURE 4 .15 A Center value of 0 makes Contrast behave like Multiply.

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NUKE 101

15 .

Move the Center slider up to 1 (

FigUrE 4.16

).

This is a Lift operation, which is covered later in this chapter. Your white point is locked, while everything else changes—the opposite of Multiply.

FIGURE 4 .16 Moving the slider up to 1 is actually a

Lift operation.

RolloffContrast has one other property you can see in the I/o graph. This property, called Soft Clip, is the property that gives this node its name. This property smooths out the edges of the curve so that colors don’t all of a sudden turn to black or white and result in a harsh transition.

16 .

Move the center slider to 0.5 and start to increase the Soft Clip slider. I stopped at 0.55.

FigUrE 4.17

shows what happens when you increase the soft clip. This creates a much more appealing result, which is unique to this node.

FIGURE 4 .17 This smooth edge to the curve is what gives rolloffContrast its name.

If you have a fair amount of experience, you must have noticed that the I/o graph looks a lot like a tool you may have used in the past—something applications such as

Adobe After Effects call Curves. In Nuke, this is called ColorLookup, and it is discussed in the next section.

cReATiNg cuRVes WiTh coLoRLookup

The ColorLookup node mentioned at the beginning of this lesson is actually an I/o graph you can control directly. This makes it the operation with the most amount of control. However, it’s actually the hardest to control and keyframe due to its more complicated user interface. After all, it’s easier to set a slider and keyframe it than move points on a graph.

Let’s try this node on both the image and the I/o graph itself.

1 .

Replace RolloffContrast2 with a ColorLookup node in the Color toolbox

(

FigUrE 4.18

).

FIGURE 4 .18

The ColorLookup interface.

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The interface for this node has the narrow curves list on the left, and the curve area on the right. Choosing a curve at left displays that curve at right, which enables you to manipulate it. There are five curves. The first controls all the channels, and the next four control the R, G, B, and alpha separately. You can have more than one curve display in the graph window on the right by Shift-clicking or

Ctrl/Cmd-clicking them in the list.

2 .

Click the Master curve in the list at left.

In the graph (Figure 4.18), you can now see a curve (a linear one at the moment).

It has two points that define it, one at the bottom left and one at the top right.

Moving them will change the color. For example, moving the top one will create a

Multiply operation.

The ColorLookup’s strength lies in making curves that you can’t create using regular math functions. For that you need to create more points.

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NUKE 101

3 .

To create more points on the curve, Ctrl/Cmd-Alt/option-click the curve in the graph window. It doesn’t matter where on the curve you click.

You’ve just created another point. You can move it around and play with its handles. If you look at the I/o graph on the Viewer, you can see that it mimics what you did in the ColorLookup node. They are exactly the same (

FigUrE 4.19

).

FIGURE 4 .19 Changing the curve is just like working with an i/O graph.

Now let’s use ColorLookup on the car image.

4 .

Select Read1 and Shift-click the ColorLookup node in the Color toolbox to branch another output.

5 .

Click ColorLookup2 and press the 1 key to view it in the Viewer.

6 .

Play around with ColorLookup2’s curves. You can play with the separate RGB curves as well.

I ended up with

FigUrE 4.20

—pretty drastic. But that’s the level of control you have with ColorLookup. The Reset button at bottom left allows me to reset this mess.

FIGURE 4 .20 Extreme color correction courtesy of ColorLookup.

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coLoR mATchiNg WiTh The gRADe NoDe

The Grade node is specifically built to make some color correction operations easier. one of these operations is matching colors from one image to another.

When matching colors, the normal operation is to match black and white points between the foreground and background (only changing the foreground), and then match the level of the midtones gray, and finally match the midtone hue and saturation.

using the grade node

The Grade node is made out of a few of the building blocks mentioned earlier.

TABLE 4.2

shows a list of its seven properties.

TaBLE 4 .2 grade Node Properties

Property

Blackpoint

Whitepoint

Lift

Gain

Multiply offset

Gamma

Definition

This is the reverse operation to Lift. It works in the same way, but higher numbers will result in stronger blacks instead of lighter blacks. Basically, the color chosen here will turn to black.

This is the reverse operation to Multiply. It works in the same way, but higher numbers will result in lower highlights instead of stronger highlights. Basically, the color chosen here will turn to white.

A Lift operation.

A Multiply operation.

Another Multiply operation.

An Add operation.

A Gamma operation.

By using Blackpoint and Whitepoint to set a perfect black and a perfect white, you can stretch the image to a full dynamic range. When you have a full dynamic range you then can easily set the blackpoint and whitepoint to match those of the background using Lift and Gain. You then have Multiply, offset, and Gamma to match midtones and for final tweaking.

Let’s practice color matching, starting with a fresh script.

1 .

If you want, you can save your script. When you are finished, press Ctrl/Cmd-W to close the script and leave Nuke open with an empty script.

2 .

From your chapter04 folder bring in two images: CarAlpha.png and IcyRoad.png.

3 .

Make sure that CarAlpha.png is called Read1 and IcyRoad.png is Read2. You can change the name of a node in the top-most property.

Note

If Nuke quits

altogether, just start

Nuke again.

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NUKE 101

You will quickly composite these images together and then take your time in color matching the foreground image to the background.

4 .

Select Read1 and press the M key to insert a Merge node after it.

5 .

Connect Merge1’s B input to Read2 and view Merge1 in the Viewer (

FigUrE 4.21

).

FIGURE 4 .21 The car is over the dashboard— this is wrong.

The composite is almost ready. You just need to punch a hole in the foreground car so it appears to be behind the snow that’s piling on the windshield. For that, you’ll bring another image in (you will learn how to creates mattes yourself in Chapter 6).

6 .

From your chapter04 folder bring in Windshield.png and display it in the Viewer.

Here you can see this is a matte of the snow. It is a four-channel image with the same image in the R, G, B, and alpha. You need to use this image to punch a hole in your foreground branch. To do that you will need another Merge node.

7 .

Select Read3 and insert a Merge node after it.

8 .

Drag Merge2 on the pipe between Read1 and Merge1 until the pipe highlights. When it does, release the mouse button to insert Merge2 on that pipe

(

FigUrE 4.22

).

FIGURE 4 .22 inserting a node on an existing pipe.

9 .

View Merge1 (

FigUrE 4.23

).

FIGURE 4 .23 All that white on the dashboard shouldn’t to be there.

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You can see here that this is not the desired result (

FigUrE 4.23

). You still need to change the Merge2 operation to something that will cut the B image with the A image. This operation is called Stencil. Stencil is the reverse operation from Mask, which you used in Chapter 3. Mask held image B inside the alpha channel of image A, and Stencil will hold image B outside image A.

10 .

In Merge2’s Properties panel, choose Stencil from the operation drop-down menu.

FIGURE 4 .24 The car is now correctly located behind the dashboard.

Looking at your comp now, you can see that it works—short of a color difference between the foreground and background (

FigUrE 4.24

). Let’s use a Grade node to fix this shift.

11 .

Select Read1 and press the G key to insert a Grade node after it.

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NUKE 101

As you know from Chapter 2, you are not allowed to color correct premultiplied images. It is often hard to tell if an image is premultiplied or not, but in this case it is.

You can also look at the RGB versus the alpha channels and see that the areas that are black in the alpha are also black in the RGB.

Since you can’t color correct premultiplied images you have to unpremult them. You can do this in one of two ways: using an Unpremult node before the color correction

(in this case, Grade1) and then a Premult node after it, or using the (Un)premult By

Switch in your Color nodes. Let’s practice both.

12 .

Bring Grade1’s offset property up to around 0.4.

You can see that the whole image, except the dashboard area, turned brighter, even though you are only correcting the car image (

FigUrE 4.25

). This is due to the lack of proper premultiplication. Let’s do the two-node method first.

FIGURE 4 .25 The whole image turned brighter.

13 .

Click Read1 and from the Merge toolbox add an Unpremult node.

14 .

Click Grade1 and from the Merge toolbox add a Premult node and look at the

Viewer (

FigUrE 4.26

).

FIGURE 4 .26 The proper premultiplication fixed the problem.

The problem has been fixed. This is one way to use proper premultiplication. Let’s look at another.

15 .

Select Unpremult1 and Premult1 and press the Delete key.

16 .

In Grade1’s Properties panel, choose rgba.alpha from the (Un)premult By menu; this automatically selects the associated check box (

FigUrE 4.27

).

FIGURE 4 .27 Using the

(Un)premult By property does the same thing as the

Unpremult and Premult nodes workflow.

The resulting image looks exactly as before (Figure 4.26). This technique does exactly the same thing as the first method, just without using other nodes. I usually prefer the first method as it shows clearly in the DAG that the premultiplication issues are handled. However, if you look at Grade1 in the DAG now, you will see that, although a smaller indication, Grade1 is showing that it is dividing the RGB channels with the alpha channel. The label now says “rgb/alpha” (

FigUrE 4.28

).

FIGURE 4 .28 The node’s label changes to show the Unpremult and Premult operations are happening inside the node.

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117

Let’s use the second method you have set up already. You will now be color correcting an unpremultiplied image, but outputting a premultiplied image. After a little

rearranging, the tree should look like that in

FigUrE 4.29

.

17 .

Bring the offset property back to 0.

FIGURE 4 .29 Your tree should look like this at this point.

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NUKE 101

using curveTool to match black and white points

Thinking back to the introduction of this section, how are you going to find the darkest and lightest points in these two images to match them together? one way, which is valid and happens often, is using your eyes to gauge which are the darkest and brightest pixels. However, the computer is so much better at these kinds of things, and doesn’t have to contend with light reflections on the screen, etc.

The Node to use for this is the CurveTool node, which you used in Chapter 3 to find the edges of the lemming element. You can also use this node to find other colorrelated stuff about your image. Let’s bring a CurveTool node in to gauge the darkest and brightest point in the foreground and use that data to stretch the foreground image to a full dynamic range.

1 .

Select Read1 and branch out by Shift-clicking a CurveTool node in the Image toolbox.

This time you are going to use the Max Luma Pixel Curve Type. This finds the brightest and darkest pixels in the image.

2 .

In CurveTool1’s Properties panel, switch the Curve Type drop-down menu to Max

Luma Pixel.

3 .

Click the Go! button.

4 .

In the dialog box that opens, click oK as you only want to process one frame.

5 .

Switch to the MaxLumaData tab and view CurveTool1 in the Viewer (

FigUrE 4.30

).

FIGURE 4 .30 The

MaxLumaData tab’s two sections.

Note

A Constant node creates a solid color with a chosen resolution.

The purpose of this operation is to find the darkest and lightest pixels in the image.

When switching to this tab you see two sections, the one showing the lightest pixel

(Maximum) and the darkest pixel (Minimum). For each, the X and Y location and RGB values display.

Looking closely you can see that the value of the minimum pixel is 0 in every property. This is because this image is a premultiplied image, and as far as CurveTool is concerned, all that black in the image is as much a part of the image as any other part of it. You need to find a way to disregard that black area. Let’s do the following.

6 .

From the Image toolbox, create a Constant node.

7 .

Change Constant1’s Color value to 0.5.

8 .

Select Read1 and branch a Merge node from it by pressing Shift-M.

9 .

Connect Merge3’s B input to Constant1, and then view Merge3 in the Viewer

(

FigUrE 4.31

).

FIGURE 4 .31 The car is on a gray background.

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What you did here was replace, momentarily, the black background with a middle gray background. This way you are getting rid of the black and replacing it with a color that is not the darkest nor the lightest in the image. This new image is the image you want to gauge using the CurveTool. You’ll need to move the pipe coming in to

CurveTool1 (

FigUrE 4.32

).

FIGURE 4 .32 Moving the pipe from read1’s output to Merge3’s output.

10 .

Click the top half of the pipe going into CurveTool1, which will enable you to move it to the output of Merge3.

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NUKE 101

11 .

Double-click CurveTool1 to display its Properties panel in the Properties Bin.

Switch to the CurveTool tab (the first one), click Go! again, and click oK.

12 .

Switch to the MaxLumaData tab again and have a look (

FigUrE 4.33

).

FIGURE 4 .33 The updated CurveTool1’s

MaxLumaData tab.

You can see now that the minimum values are far from being all 0. You are now getting a true result showing the lightest and darkest pixels. Let’s make use of them.

13 .

Close all Properties panels in the Properties Bin to clear some room.

14 .

Double-click CurveTool1, and then double-click Grade1.

15 .

View Merge1 in the Viewer.

16 .

Click the 4 icon next to Grade1’s Blackpoint, Whitepoint, Lift, and Gain to enable the four fields.

17 .

Ctrl/Cmd-drag from CurveTool1’s Minimum Luminance Pixel value’s Animation menu to Grade1’s Blackpoint Animation menu and release the mouse button to create an expression link between them.

18 .

Do the same from Maximum Luminance Pixel value to Whitepoint (

FigUrE 4.34

).

FIGURE 4 .34 The green arrow shows the expression link between the two nodes.

The foreground image’s dynamic range now spans from a perfect black to a perfect white. This enables you to push those colors to new black and white points to match these points to the background image. You’ll need to use another CurveTool to find those points in the background image.

19 .

Click Read2 and by Shift-clicking, branch out another CurveTool from it.

This time there is no alpha and no black background to worry about. You can simply proceed to finding the black and white points.

20 .

In CurveTool2’s Properties panel, choose Max Luma Pixel from the Curve Type drop-down menu.

21 .

Click Go! When asked, click oK.

22 .

When the processing is finished (you should see a quick flash of the Progress

Bar) switch to the MaxLumaData tab.

You now have two sets of data to match to: new black points and white points. Let’s link them to your Grade node.

23 .

Close all Properties panels in the Properties Bin to clear some room.

24 .

Double-click CurveTool2, then double-click Grade1.

25 .

Ctrl/Cmd-drag from CurveTool2’s Minimum Luminance Pixel value’s Animation menu to Grade1’s Lift Animation menu to create an expression link between them.

26 .

Do the same from the Maximum Luminance Pixel value to Gain (

FigUrE 4.35

).

FIGURE 4 .35 Dragging while holding Ctrl/Cmd creates a linking expression.

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NUKE 101

You have now matched the foreground’s shadows and highlights to those of the background (

FigUrE 4.36

).

FIGURE 4 .36 Shadows and highlights now match.

As you can see from the image, the shadows and highlights are matched, but the image is far from looking matched. The midtones, in this case, make a lot of difference.

matching midtones by eye

You now need to match the midtones. This is a much more difficult task. You’ll start by matching its luma level by eye. Because it is hard to tell what the midtones are, though, you are going to view the luminance of the image in the Viewer.

1 .

Hover your mouse pointer in the Viewer and press the Y key to view the luminance.

To change the midtones now, you will use the Gamma property. You can see that the whitish snow on the right is a darker gray than the whitish car. Let’s bring down the whitish car to that level.

2 .

Start dragging the Gamma slider down. I stopped at around 0.6.

Notice that the midtones don’t match well with a higher Gamma value. Now, however, the lower midtones aren’t matching well. I need to use the Multiply property to produce a good match.

3 .

Bring the Gamma slider up to 0.85 and bring the Multiply slider down a bit to 0.9

(

FigUrE 4.37

).

4 .

Hover your mouse pointer in the Viewer and press the Y key to view the RGB channels (

FigUrE 4.38

).

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FIGURE 4 .37 The midtones match better now.

FIGURE 4 .38 There is still work to be done on the color of the midtones.

oK, so the midtones’ brightness is now better, but you need to change the color of the car’s midtones. At the moment, the car is too warm for this winter’s day. Matching color is a lot more difficult as you always have three options: red, green, and blue. Matching gray is a lot easier as you only need to decide whether to brighten or darken it. However, as each color image is made out of three gray channels, you can do that to match color too. Here’s how.

5 .

Hover your mouse pointer in the Viewer and press the R key to view the red

channel (

FigUrE 4.39

).

FIGURE 4 .39 Viewing the red channel.

Now you are looking only at levels of gray. If you now change the red sliders, you will better match the color while still looking only at gray.

6 .

Display the Color Wheel and Color Sliders panel for the Gamma property by clicking the Color Wheel button.

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You will also want to change the Multiply and offset values to achieve a perfect result. This is because, even though you matched the black point and white point, the distance of the car from the camera means the black point will be higher and the white point lower. At the end of the day, it will only look right when it does, math aside.

Let’s display those extra color wheels.

7 .

Ctrl/Cmd-click the Color Wheel button for the Multiply and offset properties. Your screen should look like

FigUrE 4.40

.

FIGURE 4 .40 Opening three color wheels to easily control three properties.

8 .

Since you are looking at the red channel in the Viewer, you should change the red sliders for Gamma, Multiply, and offset until you are happy with the result.

Little changes go a long way. I left mine at Gamma: 0.8, Multiply: 0.82, and offset: 0.02.

9 .

Display the green channel in the Viewer, and then move the green sliders to change the level of green in your image. Mine is Gamma: 0.85, Multiply: 0.95, and offset: 0.025.

10 .

Do the same for the blue channel. Mine is Gamma: 0.96, Multiply: 0.95, and

offset: 0.03.

11 .

Switch back to viewing the RGB channels (

FigUrE 4.41

).

FIGURE 4 .41 Not a bad result at the end of it all.

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This is as far as I will take this comp. of course, you can use your already somewhatdeveloped skills to make this a better comp, but I’ll leave that to you.

Save your script if you wish, and we will move on.

AchieViNg A “Look” WiTh The coLoRcoRRecT NoDe

Giving an image a “look” is a very different practice than matching color. While matching color has a very specific purpose and methodology, giving an image a look refers to an artistic practice that gives an image a different feel to how it was shot.

For example, you might want it to look brighter, warmer, or colder, depending on the feeling you want to create.

using the colorcorrect node

The ColorCorrect node is a very good tool to use for this as it has a lot of control over the different parts of the image—even more control than the Grade node. But as with everything else, it is still made out of the basic mathematical building blocks covered in the beginning of this chapter.

Let’s bring in an image and give it a look.

1 .

Press Ctrl/Cmd-W to close the color matching script and start a new one.

2 .

Press the R key and bring in, from the chapter04 folder, the Car.png image again.

3 .

While the newly imported Read1 node is selected, press the C key to create a

ColorCorrect node. You can also find the ColorCorrect node in the Color toolbox.

4 .

View ColorCorrect1 in the Viewer (

FigUrE 4.42

).

Note

If Nuke quits altogether, just start

Nuke again.

126

NUKE 101

FIGURE 4 .42 The

ColorCorrect node’s

Properties panel.

As you can see in ColorCorrect1’s Properties panel, the ColorCorrect node includes controls for Saturation, Contrast, Gamma, Gain (Multiply), and offset (Add). This is performed over either the whole dynamic range—called Master—or parts of the dynamic range called Shadows, Midtones, and Highlights. This makes creating a look somewhat easier.

This idea of midtones, highlights, and shadows changes from image to image. An image of a dark room will have no whites, but in that darkness one can still define that the brighter areas will be that image’s highlights, the slightly lighter blacks will be midtones, and the darkest colors shadows. This can also be defined in the ColorCorrect node’s Ranges tab.

5 .

Click the Ranges tab in ColorCorrect1’s Properties panel.

In this tab (similar to ColorLookup, isn’t it?) you have three graphs, all selected. one represents the shadows, another the midtones, and a third the highlights

(

FigUrE 4.43

).

6 .

Check the Test check box at the top of the graph.

This shows a representation in the Viewer of what parts of the image are shadow, midtone, and highlight. Highlights are represented by white, midtones as gray, and shadows as black. Green and magenta areas represent a mix of two ranges

(

FigUrE 4.44

).

FIGURE 4 .44 The test shows the parts of the dynamic range in the

Viewer.

7 .

Click the Test button at the top of the graph again to turn it off.

The ranges are fine for this image, so we won’t change anything and we will continue working.

8 .

Switch back to the ColorCorrect tab.

You will now give this image a dreamy, car-commercial look—all soft pseudo blues and bright highlights. If you don’t define the “look” you are after in the beginning, you can lose yourself very quickly.

Before changing the color of this image, I’ll show you my preferred interface setup for color correcting.

CoLoR CoRRECTIoN

127

FIGURE 4 .43 Color-

Correct’s ranges is a lookup curve that defines the brightness ranges.

128

NUKE 101

9 .

In ColorCorrect1’s Properties panel, click the Float controls button (looks like two boxes). This will float the Properties panel instead of docking it in the Properties

Bin (

FigUrE 4.45

).

FIGURE 4 .45 Click this button to float the Properties panel.

10 .

Hover your mouse pointer in the Viewer and press the Spacebar to maximize the

Viewer to the size of the whole interface (

FigUrE 4.46

).

FIGURE 4 .46 This is a good way to set the interface for color correction.

Since the Properties panel is floating, it is still there. This way, you can look at the image at its maximum size without wasting space on things like the DAG yet still be able to manipulate the ColorCorrect node.

What I am aiming for is something like that in

FigUrE 4.47

. You can try to reach that yourself, or you can follow my steps point by point.

11 .

I’ll start by desaturating the whole image a little, so in the Master set of properties

I set the Saturation property to 0.5.

12 .

Now for the shadows. I would like to color the shadows a little bluer than normal.

Click the Color Wheel button for shadows.gamma.

CoLoR CoRRECTIoN

129

FIGURE 4 .47 This is the image look i am referring to.

13 .

From the Hue slider, choose a blue hue. I selected 0.6. Now display Saturation for the shadows.gamma color. I set it to 0.31. Finally, adjust the brightness, or Value, slider in the Color Wheel and Color Sliders panel. I have 1.22 (

FigUrE 4.48

).

FIGURE 4 .48 Setting the shadow’s gamma properties using the

Color Wheel and Color

Sliders panel.

This results in RGB values of 0.8418, 0.993, and 1.22, respectively. It gives the image a nice-looking blue shadow tint. Notice that there are actually no hue and saturation sliders in the real Properties. The hue and saturation sliders in the Color Wheel and

Color Sliders panel are only there so it will be easier to set the RGB sliders.

130

NUKE 101

Note

If you need to make the Color Wheel and Color Sliders panel bigger, drag the bottomright corner of the panel.

14 .

Close this Color Wheel and Color Sliders panel.

15 .

You have a lot more work in the midtones. First, set the Saturation to 0, so that the midtones are tinted black and white.

16 .

To create a flatter palette to work on, set the Contrast for midtones at 0.9.

17 .

To darken the midtones, set the Gamma to 0.69.

18 .

Use the Gain property to tint the midtones by clicking the Color Wheel button for midtones.gain.

19 .

In the Color Wheel and Color Sliders panel that opens, click the TMI button at the top to enable the TMI sliders (

FigUrE 4.49

).

FIGURE 4 .49 Turning on the TMi sliders.

Note

As always, only the RGB values affect the image. You just used TMI sliders to set the RGB values in an easier way.

20 .

Now, for a cooler-looking shot, drag the T (temperature) slider up towards the blues. I stopped at 0.72.

21 .

To correct the hue of the blue, use the M (magenta) slider to make this blue either have more magenta or more green in it. I went towards the green and left it at –0.11.

22 .

Close the Color Wheel and Color Sliders panel (

FigUrE 4.50

).

FIGURE 4 .50 The values are always in rgB.

23 .

You will now increase the highlights a little, so let’s start by setting the Contrast to 1.5.

24 .

To color correct the highlights, first click the 4 icon to enable the Gain slider.

25 .

Click in the right side of Gain’s first field (for the red channel) and use the arrow up and down keys to change the red value. I left it on 0.75 (

FigUrE 4.51

).

FIGURE 4 .51 The arrow keys make it easy to nudge values in fields.

26 .

Leave the next field (green) where it is, but use the arrow keys in the blue field to increase blue. Because I want everything to be a little bluer, I left mine at 1.5.

The first stage of the color correction is finished. Let’s bring the rest of the interface back.

27 .

Close the ColorCorrect1 Properties panel (

FigUrE 4.52

).

FIGURE 4 .52 First, close the floating

Properties panel.

CoLoR CoRRECTIoN

131

28 .

Press the Spacebar to bring back all your panes.

using the mask input to color correct a portion of the image

Let’s say that a movie director asks for the wheels to pop out of the image and have high contrast. To do this secondary color correction, you will need to first define an area to apply the color correction to, then use another Color node and use this area in its mask input.

You haven’t learned to create complex mattes yet, but in this case you only really need two radial mattes. You can easily create those using the Radial node in the

Draw toolbox.

First, to brighten up the wheels, you will use the Grade node.

1 .

Select ColorCorrect1 and insert a Grade node after it.

If you use the Grade node as it is, the whole image will get brighter. You’ll need to use Grade1’s mask input to define the area to work in.

2 .

With nothing selected, create a Radial node from the Draw toolbox (

FigUrE 4.53

).

132

NUKE 101

FIGURE 4 .53 Creating an unattached radial node.

3 .

View Radial1.

It creates a radial, see? I told you. By moving the edges of the radial box, you can change its shape and location.

4 .

View Grade1.

5 .

Drag Radial1’s edges until it encompasses the back wheel (

FigUrE 4.54

).

FIGURE 4 .54 radial1 encompasses the back wheel.

You’ll need another Radial node to define the second wheel. (You can add as many

Radial nodes as you need. Everything in Nuke is a node, remember?)

6 .

With Radial1 selected, insert another Radial node after it.

7 .

Adjust Radial2 to encompass the front wheel (

FigUrE 4.55

).

8 .

To make use of the radials, you will take the mask input for Grade1 and attach it to the output of Radial2, as in

FigUrE 4.56

.

FIGURE 4 .55 Using radial nodes to create masks for color correction

CoLoR CoRRECTIoN

133

FIGURE 4 .56 Attaching the mask input to the mask image.

This means whatever you now do in Grade1 will affect only where the radial’s branch is white.

9 .

Increase the whites by bringing the Whitepoint property for Grade1 down to around 0.51.

10 .

Some of the deep blacks have become a little too gray, so decrease a little on the

Blackpoint property. I left mine at 0.022.

At this point, the grading is finished. Mask inputs can be very important in color correction because a lot of times you only want to color correct an area of the image. But remember not to confuse mask inputs with mattes or alpha channels. The use of the mask input is solely to limit an effect—not to composite one image over another or copy an alpha channel across.

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INDEx

Numbers

2D compositing, inside 3D scenes,

326–333

2D data, transforming 3D data into,

268–277

2D movements, 143

2D tracking, 136. See also tracking

2D view, switching to, 270

2K, working in, 238

3D applications, scale and rotation

in, 265

3D data, transforming into 2D data,

268–277

3D render, bringing in, 63

3D scenes. See also Photoshop layers

2D compositing inside, 326–333 camera element, 258 changing View Selection, 260

compositing screen into,

334–335 creating cubes, 265–268 geometry element, 258

Grid node, 330–332 importing cameras, 263–265

ScanlineRender node, 258, 260

Scene node, 258 setting up, 259–260

3D setup, 258–260

3D Studio Max, using for camera

projection, 309

3D toolbox, described, 8

3D tracking, applying, 283

3D view, accessing, 260

3D world

camera in, 261 displaying camera axis, 262 navigating, 261–263 rotation controls, 262–263

8-bit color, explained, 98

32-bit color, explained, 98

2048×2048 image, defining, 320

Symbols

# symbol, using with numbers, 43–44

. (period), using to create Dots, 76,

78, 87, 312–313

a

Action Safe area, attaching text to,

349

Action Safe Area Knob, 357

ActionSafe property, using with User

Knobs, 344–345. See also safety

areas

Add color-correction function, 100,

105

Add node, replacing with Multiply

node, 107–108

Adrenalin Lemming, 63

All Plugins submenu, using with

Gizmos, 363–364 alpha channel, viewing, 25

Ambient occlusion pass

combining with comp, 92 described, 65

anaglyph glasses, using with stereo

trees, 254–255

animation combining with paint and roto,

185–190 identifying, 69 using keyframes in, 52–54

Animation menu, using, 41

Animator curve, example of, 54–55

ASCII file, explained, 29 assigning variables, 369

AutoCropData tab, 68 autosaves, setting preferences for, 29 axis, repositioning, 58–59

Axis node

connecting to Camera node, 265

using in camera projection,

316–317

B

Backdrop node, 106

background, placing foreground on,

71–72

background input, connecting,

24–25

background.####.png file, using with

process tree, 22–23

beauty pass

building, 73 described, 65 layering passes, 73–76 premultiplied, 85 splitting process tree, 76–83

bg.####.png file, using in 3D scene,

259 bg##.png file, opening, 178

bg.png file, using with keying nodes,

200

black and white points, matching,

118–122

blackpoint property, 113

Blending Mode property, using in

RotoPaint, 190

Blur, inserting for Reconcile3D

nodes, 277

bounding box

tightening, 70–71 using, 66–68

branches

making for passes, 76–83 starting from nodes, 31

brightness values, 100

Buddha image, placing in frame, 148 bullet_%V.####.png file, naming, 253

bulletBG_left.####.dpx file, opening,

230

bulletBG_right.####.dpx file,

opening, 230 bulletCG_left.####.ext file, 243 bulletCG_right.####.ext file, 243

buttons. See Python buttons

C

cache file, explained, 15

camera axis, displaying in 3D world,

262 camera element, in 3D scenes, 258

Camera node

connecting Axis node to, 265

using in camera projection,

312–314

camera projection

3D Studio Max, 309

720p format, 306–307 animating camera, 316–317

applying texture to buildings,

311–312

Axis node, 316–317

Axis1 connected to ShotCamera,

316–317

Camera node, 312–314 camera selection, 308–309 changing scale, 310 changing text, 308

Dots, 312–313 explained, 310 geometry in 3D Viewer, 308 importing geometry, 307 importing image, 306 manipulating Translate.x field, 310 mirror ball map, 320–321 near clipping plain, 314

Near property, 314 painting tips, 319–320 project setup, 306

Project3D node, 310–311 proxy mode for rendering, 317 relocating camera, 309–310 rendering speed, 317 replacing sky, 320–322

RotoPaint node, 318–320

ScanlineRender node, 312–314

Scene node, 312–314 shade geometry, 310–311 square_2k format, 320

texture setup for geometry,

310–312

378

NUKE 101

tracking shot, 318–320 tweaking geometry, 315–316 tweaking texture, 318–320

Write node for rendering, 336

Camera Tracker. See also reflection; tracking

2D and 3D scenes in Viewers, 289

3D view, 288 aligning scenes, 287–292

CameraTracker tab, 283 connecting Viewer, 289

Create Scene, 281 creating scenes, 286–287 creating Viewer in pane, 289

defining ground plane on axes,

290 defining points, 290

Film Back Size property, 285 improving tracks, 282

Mask input, 283 nodes, 286–287 point cloud in 3D Viewer, 288 points representing table, 292 removing extra Viewer, 292 running tracking process, 283 selecting points for Z axis, 291 selecting points on table, 290

setting Z axis for ground plane,

291

Solve Camera, 281, 285 solved tracks, 285

Solver tab, 284–285 splitting pane horizontally, 288

Track Features, 281, 283 tracking features, 282–284

Tracking tab, 282 using, 281

Viewers side by side, 290

camera tracking, calculating

reflection movement, 280–281

cameras

importing in 3D scenes, 263–265 viewing in 3D world, 261 nodal, 277

CameraTracker node, 280, 287

candle flames, adding flares to,

140–142

car commercial look, creating,

127–128

Card node, using with reflective

surface, 295–298

CarWindow.png file, opening, 185

CGI images

adding, 87–91

placing over live backgrounds,

91–93 channel display box, 13

channel sets

combining, 74

JPEG file format, 62 listing, 64

PNG file format, 62

PSD file format, 62 pulling information from, 91

RGBA, 62

TIFF file format, 62 viewing with Viewer, 63–65

Channel toolbox, described, 7

channels

copying between branches, 84 maximum number of, 62 mixing from channel sets, 77 moving, 50–51 using Mask input with, 93–95

Check Box Knob

linking to expression, 362 setting up, 361

Christmas2K file, naming, 232 chroma-keying, explained, 198. See

also HueKeyer keying node

CLEAN ME, writing on car window,

189

clipped color, explained, 99

clips

playing in Viewer, 15–16 slowing down, 246

Clone brush, using in RotoPaint,

175–176

Cmd key, 7

Col pass, adding, 81 color channels, viewing, 13–14

color correcting

highlights, 130–131

images, 36

portions of images, 131–133

unpremultiplied images, 117

color correction

dynamic range, 100–105

functions, 100

interface setup, 127–128

limitation of, 26–27

nodes, 36, 103–104

color difference-keying, explained,

198 color management, 227

color matching, using Grade node,

113–117

color operations, visualizing, 105–110

Color pass, 65

Color Picker button, locating, 86 color pickers, unchecking, 212

Color Sliders panel

closing, 86

enlarging, 130

using, 40–41

using in dynamic range, 101

color space conversion, applying,

234–235

Color toolbox, described, 7

Color Wheels

closing, 86

displaying, 124

enlarging, 130

using, 40–41

using in dynamic range, 101

ColorBars node, using with Gizmo’s

tree, 352

ColorCorrect node

brightness ranges, 126–127

Properties panel, 126

Ranges tab, 126–127

using, 125–131

ColorLookup tool, creating curves

with, 110–112

colors

32-bit, 98

capturing from screen, 212

clipped, 99

dealing with, 105

normalized values, 99

sampling from Viewer, 86

Colorspace option, using with stereo

script, 234

Colorspace property, in Proxy

System, 241

Command key, 7

commands

creating in Python, 371 expressions as, 69–71

composites

building for process trees, 22–23 creating, 24–25 starting, 20 viewing without rendering, 51–52 compositing, defined, 24 compression property, changing, 44

Constant node, creating, 118–119

ContactSheet node, using, 65–66

Content menu, 3 contextual menu, 6

Contrast color-correction function,

100, 105

contrast operation, performing, 109

controls, 35 copying Gizmos, 364

CornerPin node specifying source corners,

152–154 using in Fly Ginza example, 334 using with Tracker, 149–150, 152

Crop node, using, 69–71

Ctrl key, 7

cubes applying checkerboard texture,

265–266 creating in 3D scenes, 265–268

Downrez option, 267

Proxy mode for playback, 267 relocating, 266–267

INDEX

379

seeing over background, 267 tracked camera, 267

Current Info panel, using with scripts,

29–30

Curve Editor, 3. See also RotoPaint vs. Dope Sheet, 192 moving around in, 173 switching between Node Graph, 3 using, 54–55, 170–174 curve interpolation, 172

curves

creating, 170 creating points on, 112, 173 fitting to window, 171 loading onto Curve Editor, 41

smoothing edges of, 110

CurveTool, using, 68, 118–122

D

DAG (Directed Acyclic Graph), 2–3,

23, 235–236 decimal point numbers, changing, 54

deleting

keyframes for tracks, 146 nodes, 34 strokes, 165

Difference keying node, 199 different-keying, explained, 198 diffuse pass, creating, 74

Display Gain slider, 276. See also

Gain property

Display Gamma slider, 276. See also

Gamma property

display resolution, scaling down, 238.

See also resolution doll image

alpha channel, 25 changing color of, 38–39 color correcting, 36 making darker, 41

placing over background image,

24–30

Dope Sheet, 3, 249 vs. Curve Editor, 192 displaying timing in, 249 using, 191–196

Dots

creating, 87

using in camera projection,

312–313 using to organize nodes, 76–79 using to organize trees, 92 using with Groups, 355

Downrez option, using with cube, 267

Downscale Resolution option, 238,

240

Draw toolbox, described, 7

Drop Shadow pass, described, 65 dust, removing with paint, 176–178

dynamic range

brightness values, 100

highlights, 100, 102

midtones, 100, 102–103

shadows, 100

E

EdgeDetect node, using with Gizmos,

339

Edit Expression panel, using with

TCL, 349

Edit menu, 4

erode algorithms, using with mattes,

217–221

Erode filter, using on sky, 325–326

Export as Gizmo button, 363

Expression node, locating, 106

Expression panel, using with Tracker1

node, 151

expressions

changing for Groups, 358–359 changing for User Knobs, 345,

347 linking properties with, 69–71, 151 writing, 151–152 writing for Gizmo’s tree, 341 eyes, adding to lemming, 89–91

Eyes pass, described, 65

F

Feather Falloff property, using in

RotoPaint, 167–168 fg##.png file, opening, 178

File Browser

anatomy of, 9 launching for RotoPaint, 183 multiple-selecting files in, 22 using, 10–11 using with process tree, 22 viewer, 10

File menu, 4

file sequences changing compression settings,

44 frame padding structure, 43

LZQ compressor, 44 naming, 43–46 rendering, 43–46

Filter toolbox, described, 8 filtering, occurrence of, 142 filters, applying, 86

Flare node, using, 140

flipbooks, loading in Framecycler,

16–17

float, explained, 98–99

flows, trees as, 20

Fly Ginza example

adding highlight to frame, 335 background layers, 331

compositing screen in 3D scene,

334–335

CornerPin node, 334

creating frame for screen,

332–333 matte added to buildings, 335

Merge node, 334

Ramp node, 334–335 rendering scene, 336 screen in perspective, 334 screen tree, 333 setting Alpha value, 335

X and Y Number fields for grid,

331

Fly Ginza logo, 329

Fly Ginza poster, 327 footage, importing, 9

foreground, placing over

background, 71–72

format, determining for stereo script,

232 four point tracking, 143

FPS (frames per second) field,

displaying in Viewer, 15 setting, 15

frame padding structure, applying to

files, 43

frame range changing in Project Settings

panel, 248 controlling for Viewer, 226

frame_v01.nk file, using with camera

tracking, 280–281 frame_v02.nk file, saving, 281

Framecycler playback system

defining frame ranges, 17 features of, 16 loading flipbooks, 16–17 maximizing, 18 shortcuts, 17–18

frames

advancing, 54 creating for pictures, 148–149 indicating keyframes on, 54 inventing in-between, 246

Furnace Core toolbox, described, 8

G

Gain property, using with stereo

projects, 252. See also Display

Gain slider

Gamma color-correction function,

100, 105

Gamma curve, using, 108–109

Gamma property. See also Display

Gamma slider

knob for, 39

using with midtones, 122–125

380

NUKE 101

Gamma slider, turning into numeric

fields, 40 garbage matte, creating, 216, 219

geometry element

in 3D scenes, 258 for reflection, 301

ginza_moving.####.png render,

naming, 336

Ginza.jpg, opening for camera

projection, 306

Gizmo. See also TCL scripting language; User Knobs

creating User Knobs, 342–348

Export as Gizmo button, 363

Noop node, 342 percentage values, 342–348

User Knobs panel, 342–343

Gizmo hot key, creating, 371

Gizmos. See also nodes

converting to Groups, 365–366 copying, 364 creating icons, 374 defined, 338 installing for Groups, 363 safety areas, 338–339 testing for Groups, 363–364 tips, 365–366 turning Groups into, 362–364

Viewer Input Process, 364–365

Gizmo’s tree

building, 339–342

ColorBars node, 352

connecting Rectangle nodes,

352–353

EdgeDetect node, 339 expression, 341 outline for Action Safe guide, 340

Rectangle1, 340, 342 removing overlays, 341 testing, 352–353

X property, 341 good_track script, importing, 148.

See also tracking

Grade node, 36

blackpoint property, 113 gain property, 113 gamma property, 113 lift property, 113 multiply property, 113 offset property, 113 properties, 113

unpremultiplying images, 250

using for color matching, 113–117

using Mask input with, 94

whitepoint property, 113

graphic user interface (GUI). See GUI

(graphic user interface)

Grid nodes, using in 3D scene,

330–332

Group nodes, Show button in, 354

Group output panel, 354

Group1 Node Graph, 355

Groups. See also trees

adding functions to, 360 changing expressions, 358–359 converting Gizmos to, 365–366 creating, 354 defined, 353 turning into Gizmos, 362–364

User Knobs in, 353, 355 using Dots with, 355 using Knobs with, 355–356

Viewer Input Process, 364–365

gs.tif file, using with keying nodes,

200

GUI (graphic user interface)

components, 2–3

Context menu, 3 contextual menu, 6

Curve Editor, 3 customizing, 4–6

DAG (Directed Acyclic Graph),

2–3 default layout, 2

Dope Sheet, 3, 249 getting back, 3 hot keys, 6–7 menu bar, 4–6

New Viewer, 4

Node Graph, 2–3

Nodes Toolbar panel, 2–3 panels, 3–4 panes, 2

Progress Bar, 4

Properties Bin, 3

Script Editor, 4

Viewer, 2

h

hair, adding to lemming, 87–89

Hairs pass, described, 65

Help menu, 4

high contrast image, producing, 104

highlights, 100

color correcting, 130–131

matching shadows with, 122

representing, 126–127

hi-res images. See also stereo script

using proxies with, 238–242

Viewer Downscale Resolution

option, 238, 240 hot keys, 6–7

3D view, 261 adding with Python, 371

Bézier in RotoPaint, 167 creating for Gizmo, 371

Current Info panel, 29

Edit Expression panel, 349 identifying, 29 keyframe selection, 171

Merge node, 24 overlays, 341 for playing clips in Viewer, 15 rendering versions, 57

RotoPaint, 168 for saving, 6 saving scripts, 45 for Viewer, 13

HSV slider, using, 40

HueCorrect node, using to remove

spills, 220–222

HueKeyer keying node. See also chroma-keying

changing point on graph, 203 default alpha channel, 201 editing curves, 202–203 editing graphs, 202 explained, 199 using, 201–203

I

IBK (Image Based Keyer) keying

node, 199–200

Blue/Green Weight property, 207,

209 clean plate, 203–205

Darks and Lights, 205

Erode property, 206

IBKColour node, 203–204

IBKGizmo node, 203–204,

207–209

Luminance Level property, 207

Luminance Match property, 207,

209

Merge node, 208

Patch Black property, 207 plate, 203

Red Weight property, 207, 209 result of, 216 setting up IBK tree, 204 using, 203–210

Weight properties, 208

icons, creating and adding with

Python, 372–375

ID pass, described, 65

image appearance. See process trees image area, defining for processing,

67–68

image resolution

defining, 106

displaying, 23

Image toolbox, described, 7

images. See also nonlinear images; premultiplied images; shots

color correcting, 36 comparing, 58–59

finding darkest pixels in, 118–122 finding lightest pixels in, 118–122

merging, 24–30 playing in realtime, 15

INDEX

381

premultiplied, 25–28 previewing, 10 shrinking to half resolution, 72 viewing, 13–14 importing footage, 9 in-between frames, inventing, 246

Incidence (Inc) pass

adding to composite, 81 changing color of, 85 described, 65

Indirect Light pass, described, 65

I/o graph

default state, 107

using with color operations,

105–110

J

JPEG file format, channel sets, 62

K

keyboard shortcuts. See hot keys

Keyer keying node, 200

Keyer toolbox, described, 8

Keyframe window, keyframing, 193

keyframes

changing timing of, 191–196 creating, 41 deleting for tracks, 146 indicating on frames, 54 selecting all, 171

setting with Write on End field,

191 using in animation, 52–54

keying nodes

combining using tree, 216–223

Difference, 199

HueKeyer, 199, 201–203

IBK (Image Based Keyer),

199–200, 203–210

Keyer, 200

Keylight, 200, 210–215

Primatte, 200

Ultimatte, 200 keying terminology, 198

Keylight keying node, 200. See also

mattes; spills

Bg input, 211–212 choosing output modes, 214–215

Clip Black property, 214

Clip Rollback property, 214 controls, 213–214 drag action, 212

Gain controls, 213 garbage matte input, 211, 216 holdout matte input, 211

InM (inside matte) input, 211 locating controls, 213 outM (output matte) input, 211 result of, 216 sampling colors, 212

Screen Gain property, 212–213

Screen Matte options, 214

Source input, 211

Tuning submenu, 213 using, 210–215

KeyMix node

compositing with, 187–188 using with Reconcile3D, 276

KnifeCU.###.png file, opening, 174

Knobs. See also properties; User

Knobs

adjusting, 38–39 for check box, 361 creating for Which property, 361

Pick Knobs to Add panel, 356 as properties, 342 properties for, 356 using with Groups, 355–356

L

LayerContactSheet node, using,

65–66

layers. See channel sets; Photoshop layers

Layout menu, 4

lemming

adding hair and eyes to, 87–91

compositing over background,

71–72 lemming render passes, 65

lemming tree, placing over

background, 91–93

lemming_v01.####.png, using in 3D

scene, 259

Lgt pass branch, 78

Lift color-correction function, 100

Lift operation, 104, 110

Light pass, described, 65 linear, converting log images to, 234

linear color, explained, 99

lines, removing, 88–89 linking expression, creating, 69

log to linear, converting images to,

234

Lookup color-correction function, 100

luma-keying, explained, 198

LUT (lookup table) settings, 227–229 displaying graphs, 228–229 for editing, 228–229 for image types, 228–229 using with stereo script, 233–235

LZQ compressor, using with file

sequences, 44

M

Mask input color correcting parts of images,

131–133

using, 93–95 using with Camera Tracker, 283 mask operation, performing, 90–91

mattes. See also Keylight keying node

creating for unwanted areas, 216 crunchy type of, 216 dilating and eroding, 217–221 using, 47–52

Max Luma Pixel Curve Type, 118

maya.png file, using with process

tree, 22–23 menu bar, 4–6

menu.py file, using with Python,

372–375

Merge nodes

connecting for beauty pass, 73 creating, 24 layering operations, 24, 48 over layering option, 48

Stencil operation, 49

treatment of foreground images,

26–27

treatment of premultiplied

images, 26–27 using in Fly Ginza example, 334

using with Ambient occlusion

pass, 92 using with channel sets, 91 using with mattes, 219 using with RotoPaint, 186

Merge toolbox, described, 8

merging

images, 24–30 premultiplied images, 26–28

Metadata toolbox, described, 8

midtones, 100, 102–103

matching by eye, 122–125

representing, 126–127

using Gamma property with,

122–125

mirror ball map, using with sky,

320–321 mix slider, using, 74–75

motion blur

adding, 154–157 properties, 154–155 turning on, 184

VectorBlur filter node, 156 motion vectors, generating, 155

MotionBlur2D node, connecting, 155

movement, creating with Tracker

mode, 143–144

Multiply color-correction function,

100, 105

Multiply node, replacing Add node

with, 107–108

multi-view node, identifying, 244

382

NUKE 101

N

New Viewer, 4 nodal camera, 277

Node Graph, 2–3 enlarging, 3 switching between Curve Editor, 3 node indicators, using, 54–57

nodes. See also Gizmos; process trees

anatomy of, 22 arranging, 34 branching, 30–32 cloning ScanlineRender, 323–325 connecting, 32–33 connecting to Viewer, 11–12 creating, 7–8, 30–32 deleting, 34 deselecting, 33 disabling, 28, 34 inserting, 30–32 inserting to pipes, 49 multi-view, 244 naming, 8 organizing, 78

placing on pipes, 114

replacing, 31–32 resetting properties of, 35 selecting, 33

Shuffle, 50–51 starting branches from, 31

Nodes menu, calling in Python,

369–370

Nodes Toolbar, 2–3, 7–8 noise, removing, 219

Noise node, using with RotoPaint,

185–186

nonlinear images. See also images

Log, 228 settings for, 227–229 sRGB, 228

Noop node, using in Gizmo, 342,

344–345

normalized values, explained, 99

.nuke directory, locating, 363

Nuke interface. See GUI (graphic user interface)

Nuke scripts. See scripts

NukeX license, 280 numbers, formatting, 43

O

oFlow (optical flow) node, using with

stereo projects, 246–247 one point tracking, 143

openEXR file format, channel sets,

62–63 other toolbox, described, 8

P

paint combining with roto and

animation, 185–190 dust removal with, 176–178 using for wire removal, 175–176 painting in practice, 174–178. See

also RotoPaint

Panasonic HVX-200 camera, 285

panels

Curve Editor, 3 locating names of, 3 vs. panes, 2 panes, 2 moving divide between, 3 vs. panels, 2 splitting, 5

panorama. See reflection maps

parallax, defined, 280

passes

combining, 74–76 connecting, 82 defined, 62 diffuse, 74 layering, 73–76 making branches for, 76–83 manipulating, 85–87 rendering, 64–65 unpremultiplying, 78

pattern box, use with tracker point,

136 period (.), using to create Dots, 76,

78, 87, 312–313 perspective movement, 143

Photoshop layers. See also 3D scenes

alpha channel, 328–329 channel sets, 327 determining opacity, 329 importing, 326–333 layering operations, 327 splitting, 328

picture

placing in frame, 148–152 tracking in frame, 144–146

pipes

changing course of, 76–77 moving between nodes, 32–33 moving for HueCorrect, 222

placing nodes on, 114

pixel, defined, 62 pixel aspect ratio value, entering, 233

pixel-based properties, using in

Proxy System, 239

PNG file format, channel sets, 62

PNG file sequence, rendering,

253–254

points

changing locations of, 173 creating on curves, 112, 173

position data

accumulating, 136 applying, 136

Premult option, accessing, 27–28

premultiplied images. See also images

merging, 26–28 stereo-view proxies, 244

unpremulting, 116

unpremultiplying images, 250 previewing images, 10

Primatte keying node, 200 process trees, 20–21. See also

Groups; nodes

adding functions to, 360 controlling timing in, 191–196 creating, 22–23 displaying image resolution, 23 flow of, 20–22

highlighting areas in, 106

organizing, 76–77, 92 rendering, 42–43 splitting, 76–83

Viewer Input Process, 364–365 processing, speeding up, 66–68, 70

Progress Bar, 4 moving, 4–6 panels, 5, 45

project files. See scripts

Project Settings panel

changing frame range in, 248 displaying, 226

LUTs (lookup tables), 227–229 nonlinear images, 227–229

Root tab, 226–227

Views tab, 229–230 project speed, determining, 226–227

properties. See also Knobs

adjusting, 38–39 changing, 35–41 keyframing, 52–54 as knobs, 342 linking with expressions, 69–71 manipulating, 38–39

Properties Bin, 3 clearing, 38 editing properties in, 38 loading Properties panel in, 37 locking, 38 panels in, 37

removing Properties panels from,

38 using, 37–38

Properties panels, 11

Float panel button, 38

floating, 128

opening, 38

proxies. See also stereo-view proxies using with hi-res images,

238–242 using with stereo script, 238–242

INDEX

383

Proxy files, renaming, 242 proxy images, generating, 240–241

Proxy mode

effect of, 72 toggling on and off, 240 using in camera projection, 317 using with cube, 267

Proxy System

Colorspace property, 241 pixel-based properties, 239

Proxy Scale property, 239

Read node, 238 rendering views in, 241–242 turning on, 240

Viewer, 239

PSD file format, channel sets, 62

Python buttons

Clear History, 369

Clear output, 369 creating, 369–371

Load Script, 369

Next Script, 369

Previous Script, 369

Run the Current Script, 369

Save Script, 369

Show Both Input and output, 369

Show Input only, 369

Show output only, 369

Source Script, 369

Python scripting language, 368. See

also TCL scripting language

adding hot keys, 371 calling up Gizmo, 370 calling up Nodes menu, 369–370

creating and adding icons,

372–375 creating buttons, 368 creating commands, 371 creating menus, 370 customization, 372–375 menu.py file, 372–375 menus, 368

Nodes toolbar, 368 running commands, 370

Script Editor, 368

User menu, 371

R

Radial node, creating, 131–132

Ramp node, 106, 334–335

Raw Data option, using with stereo

script, 233–234

ray tracing, using in reflection,

298–299

Read nodes connecting into Multi-view

stream, 237 connecting via Views, 236 creating, 9–10, 47 in DAG, 23

in DAG (Directed Acyclic Graph),

235–236 in Proxy System, 238 using versioning system with, 57 using with process tree, 22 using with stereo script, 243–246

Write node as, 45 realtime, playing images in, 15

Reconcile3D nodes

axis placement, 268–270 connecting parts of, 270–271 creating RotoPaint node, 273–274 determining image resolution, 271

Display Gain slider, 276

Display Gamma slider, 276

Execute panel, 272 identifying reference frame, 275 inserting Blur, 277

KeyMix node, 276 setting up, 268–273

Translate properties, 273

Translate.x values, 270 turning on Tracker 2, 275

using output with Tracker node,

273–277

Rectangle nodes, connecting for Safe

Area tool, 352–353 redo functionality, 38

reflection. See also Camera Tracker

adding to frame image, 302–303 creating, 292 cutting to size, 302–303 environment light, 298–302

image projected on Card node,

301 importing script, 292–293 masking, 302–303

Merge operations, 302–304 optimizing tree, 301 panorama image, 300 placing over composite, 302–303 ray tracing, 298–299 rotating image, 302

ScanlineRender node, 293–296,

300–301

Scene node, 299 specular materials, 298–302

Transform node, 301

reflection maps

panorama in 2D, 295 panorama in 3D Viewer, 294 qualities of, 293

reflection movement, calculating,

280–281

reflective surface

Card node, 295–298 creating, 296–298

Reformat node, 106, 295–296

Render button, locating, 44

Render dialog box, using with

RotoPaint, 184

Render menu, 4 render passes, 65

rendering

choosing paths for, 43 file sequences, 43–46 moving images, 43–46 naming file sequences, 43–46 new versions and comparing, 57 with Write node, 42–43

resolution. See also display resolution defining for stereo script,

231–233 setting for images, 227

Retime node, using, 247–248 retiming elements, 246–249

Reveal brush, using in RotoPaint,

177–178

RGB slider, using, 40

RGBA channel set, 62

RolloffContrast operation, 104, 110

Rotate properties, using on sky, 325

roto, combining with paint and

animation, 185–190

RotoPaint. See also Curve Editor; painting in practice

animating shapes, 168–169

Bézier hot keys, 167

Bézier tool, 161

Blending Mode property, 190

Blur tool, 161

Brush tool, 161

B-Spline tool, 161

Burn tool, 162

changing length of strokes,

163–164

Clone brush, 175–176

Clone tool, 161

compositing with KeyMix node,

187–188 connecting Viewer inputs, 181 deleting strokes, 165

Dodge tool, 162

Dope Sheet, 191–196 drawing shapes, 166–168 editing shapes, 166–168 editing strokes, 163–165

Ellipse tool, 161

Eraser tool, 161 erasing strokes, 165

Feather Falloff property, 167–168 hot keys, 168 launching File Browser, 183

Lifetime properties, 163–164 locking shapes, 181

Merge node, 186 motion blur, 184

Noise node, 185–186

384

NUKE 101

on-screen controls, 160 painting in practice, 174–178 painting in vectors, 164–165 painting strokes, 162–163 pulling out soft edge, 168

Rectangle tool, 161

Render dialog box, 184 reordering strokes, 165

Replace option, 185

Reveal brush, 177–178

Reveal tool, 161 scaling brush sizes, 162 shape-drawing tools, 161

Sharpen tool, 162

ShuffleCopy node, 182

Smear tool, 162 split screening twins, 178–184 stroke-drawing tools, 161–162

Stroke/Shape List window,

188–190 switching between buffers, 181

Tool Settings bar, 161–162

Toolbar, 161 transforming groups of points, 167

RotoPaint nodes

creating, 176 loading, 160

using in camera projection,

318–320 using with Reconcile3D, 273–274

S

Safe Area tool, beta testing, 352–353

Safe Area tree, displaying, 354

SafeAreas Group, naming, 362 safety areas, 338–339. See also

ActionSafe property

boxes for, 347–348 creating for titles, 346 moving boxes for, 349

Saturation color-correction function,

100

Save New Version option, 29–30 saving scripts, 29–30

ScanlineRender node

in 3D scenes, 258, 260 cloning nodes, 323–325

Projection Mode, 294

Reformat node, 295–296 using for reflection, 293–296

using in camera projection,

312–314 using with reflection, 300–301

Scene node

in 3D scenes, 258

using in camera projection,

312–314

Script Editor, 4

scripts. See also stereo script; TCL script manipulating in text editors,

359–362 saving, 29–30, 45

Self Shadow pass, described, 65

sequences. See file sequences settings. See Project Settings panel

Shadow pass, subtractive, 82

shadows, 100

matching with highlights, 122

representing, 126–129 setting Gamma properties, 129

shapes

animating, 168–169 drawing, 166–168 editing, 166–168 shots, stabilizing, 137–142. See also

images

Shuffle node, using, 50–51

ShuffleCopy node

using, 84–85 using with HueCorrect, 221–222 using with RotoPaint, 182

sky

adjusting color of, 325 applying Rotate properties to, 325

Erode filter, 325–326

replacing with

SphericalTransform, 320–322

SkyDome.png file, opening, 320

slap comps

in stereo projects, 250 using, 72

sliders

adjusting, 38–39 switching between fields, 40–41 slowing down elements, 246–249

Soft Clip property, 110

specular, defined, 299

Specular pass

branch, 87 described, 65

SphericalTransform, using to replace

sky, 320–322

spills, suppressing with HueCorrect

node, 220–222. See also Keylight

keying node

SplitAndJoin node, using with stereo

projects, 251 split-screen shape, 180

SplitScreen.####.png sequence,

naming, 183 spoon position, tracking, 137–139

square_2k format, using with sky,

320

stabilize.####.tif sequence, loading,

137 statue.jpg file, opening, 148

Stencil operation

using with Grade node, 115

using with mattes, 219 using with Merge node, 49

stereo projects changing properties for views,

251–253 compositing, 245–253

compositing elements together,

249–251

Gain property, 252

JoinViews node, 251–252

manipulating views apart from

properties, 252 oneView node, 251–252 optical Flow, 246

placing foreground over

background, 249–250 retiming elements, 246–249 slap comp, 250

SplitAndJoin node, 251 unpremultiplying images, 250,

253

stereo script. See also hi-res images; scripts applying color space conversion,

235

Colorscript drop-down menu, 234 defining resolution, 231–233

LUT (lookup table) settings,

233–235 setting formats, 231–233 using proxies, 238–242

stereo trees

Colorspace property, 253

Data Type property, 253 rendering and viewing, 253–255 using anaglyph glasses, 254 stereo views, 235–238

stereo-view proxies. See also proxies

alpha channel, 244–245 applying color management, 244 creating, 243–246 premultiplied images, 244 views for rendering, 245

Write nodes, 245

streams

connecting in multi-view tree, 237 creating via branching, 31

strokes

deleting, 165 editing in RotoPaint, 163–165 erasing, 165 painting in RotoPaint, 162–163 reordering, 165

Stroke/Shape List window, using in

RotoPaint, 188–190 student_files folder, creating, 42–43

Switch node, connecting, 360–361

Switch Properties panel, 361

INDEX

385

T

TCL script, typing, 77. See also scripts

TCL scripting language. See also

Gizmo; Python scripting language

Action Safe text in Viewer, 350 adjusted expression, 350–351

attaching text to Action Safe area,

349 inserting Text node, 348 linking expression, 349

Message input field, 350 moving box for safe area, 349

Title Safe area, 350–351

Transform group, 348–349 using, 348–351

text editors

adding functions, 360

Check Box Knob, 361–362 connecting Switch node, 360–361

creating Knob for Which property,

361 editing expressions, 361–362 manipulating scripts in, 359–362

search and replace functions,

359–360

Text node, inserting for TCL, 348

TextEdit, Find dialog box, 359–360

TIFF file format, channel sets, 62

Time toolbox, described, 7

timing of elements

dealing with, 246–249 showing in Dope Sheet, 249

Title Safe area, creating, 350–351

Title Safe area Knob, 358

TMI slider

turning on, 130

using, 40

Track Forward button, 138

tracked data, changing to

transformations, 139

Tracker node

features of, 136–137 position data, 136

Properties panel, 137–138

using Reconcile3D’s output with,

273–277

using to create movement,

143–144

using with CornerPin node,

149–150 tracker point, anatomy of, 136

Tracker Properties panel, Transform

tab, 139

Tracker Settings tab

Epsilon parameter, 146–147 max_error, 147 properties on, 146–148

tracking. See also 2D tracking;

Camera Tracker; good_track script

improving, 145–146 picture in frame, 144–146 types of, 143

tracking points

overview, 143–144 tracking, 144–146

tracks

deleting keyframes for, 146 stopping, 146

Transform group, using with TCL,

348–349

Transform node

geometry, 301 inserting, 30–31 using with reflection, 301

Transform toolbox, described, 8

Transformation controls, using,

35–36

transparencies. See Keylight keying node

trees, 20–21. See also Groups; nodes adding functions to, 360 controlling timing in, 191–196 creating, 22–23 displaying image resolution, 23 flow of, 20–22

highlighting areas in, 106

organizing, 76–77, 92 rendering, 42–43 splitting, 76–83

Viewer Input Process, 364–365

TV screen, creating, 326–335 two point tracking, 143

U

Ultimatte keying node, 200 undo/redo functionality, 38 updating Viewer, 235

User Knobs. See also Gizmo; Knobs

ActionSafe property, 344–345 changing expressions, 345, 347 defining properties, 343–344 in Groups, 353, 355 naming tabs, 344 replacing percentages, 345 safety area for titles, 346 settings for, 346 shuffled alpha channel, 347

TitleSafe, 347 using in Gizmo, 342–348

Width/Height Knob panel, 343,

345

User Knobs panel

entries in, 356–357 operation Knob, 358 ordering Knobs in, 358

V

values, manipulating, 54

VectorBlur filter node, using, 156 vectors, painting in, 164–165

versioning system, using with nodes,

57 versions, comparing, 58–59

Viewer, 2 anatomy of, 12

Channel buttons on, 65 connecting nodes to, 11–12 controlling frame range of, 226 enlarging, 3 features of, 11 fps field, 15 hot keys, 13, 15 inputs, 14–15 navigating, 12–13 opening, 4 pausing, 235 playing clips in, 15–16 in Proxy System, 239 sampling colors from, 86 updating, 235 using, 13–14

Viewer Downscale Resolution option,

238, 240

Viewer Input Process, using,

364–365 viewers, adding and connecting, 4

Views

buttons in Viewer, 237 listing, 236 managing, 230

manipulating apart from

properties, 252

using to connect Read nodes,

236

Views toolbox, described, 8

View-specific nodes, location of, 237

W

wheels, brightening up, 131–132

white and black points, matching,

118–122

whitepoint property, 113

window layout, controlling, 3–6 windows, turning into Node Graph, 3

Wipe option, turning on, 58–59 wire removal, using paint for, 175–176

Write nodes

as Read nodes, 45 stereo-view proxies, 245 using, 42–43 using in camera projection, 336 using versioning system with, 57 with thumbnails, 45–46