PREPARING SYBIL IHRIG EMIL IHRIG

Transcription

1 PREPARING FOR P R I N T SYBIL IHRIG EMIL IHRIG Osborne McGraw-Hill Berkeley New York St. Louis San Francisco Auckland Bogota Hamburg London Madrid Mexico City Milan Montreal New Delhi Panama City Paris Säo Paulo Singapore Sydney Tokyo Toronto

2 Foreword vii Acknowledgments ix Consider the Source i Scanned Images 2 Medium of Original 2 Scanner Type and Characteristics 3 Preprocessing 6 Photo CD Images 7 Enhancing Photo CD Images on the Fly 7 Images from Digital Cameras 9 Digital Stock Photos 10 Royalty-Free Collections 10 Stock Agency Collections 11 Online Picture Services 11 Video and Computer Screen Captures 12 Original Digital Illustrations 12 Working the System How Much System Is Enough? 13 Document Type and Audience Expectation 14 n Press Setup 14 Screening and Separation Technology 14 Volume of Work 15 Print Dimensions 15 Bus and Processor Speed 15 System Memory (RAM) 16 Input 16 Display System 17 Monitor Calibration Devices 17 Scanners 18 Digital Cameras 18 CD-ROM Drives 18 Graphics Tablets 18 Image Storage 19 Internal Hard Drives 19 Removable Drives 19 Optical Drives 20 Tape Options 21 Digital Transmission 21 Software Solutions 21 Image-Editing, Paint, and Compositing Software 21 Filters 22 Color Management Systems 23 Productivity Software 23 Page Composition Software 24 Output and Proofing Devices 24

3 iv Screening and Print Reproduction Basics 2s Digital Halftoning Basics 26 Screen Frequency, Tonal Range, and Detail 26 Dot Shape 29 Screen Angle, Patterning, and Output Resolution 30 FM Screening Alternatives 34 FM Screening Advantages 36 FM Screening Challenges 36 Tuning in to FM 38 Color Reproduction and Management 39 Color Spaces 40 Perceptual Color Spaces 40 Additive Color Spaces 42 Subtractive Color Spaces 42 Color Depth 44 Color Printing Devices 45 Separated Color 47 Spot Color and Duotones 47 Process Color 47 HiFi Color 48 The Color Management Quest 48 Proofing for Print Reproduction Pitfalls 50 Print Reproduction Pitfalls 50 The Calibration Process 51 Types of Proofing 51 CMS Principles 55 Managing Color The Process 56 CMS Solutions 57 Color Management at the Operating System Level 60 Apple ColorSync 2 60 Kodak Color Matching in Windows Light Source Colortron 61 Image-Editing and Enhancement Tools 63 Managing Large Image Files 64 Knowing When to Crop 64 To Edit or Not to Edit in CMYK 64 Extra Channels and Multiple Layers 65 Image-Enhancement Tools 68 Retouching Tools and Techniques 68 Tools for Selective Enhancement 70 Histograms 71 Densitometer Tools 73 Curves 73 m Color Separations and Conversions 7s Color Separation Decisions 76 Avoid Multiple Conversions 76 Total Ink Coverage 77 Total Ink Limit 77 SWOP to the Rescue 77 Managing the Black Channel 78 Setting Paper and Ink Parameters 82 Gray Balance: Neutral Is Not Equal 84

4 v From Color to Black and White 87 Why Black and White Falls Flat 87 Evaluating Color for Contrast 88 Retaining the Color in Gray 90 Scanning Color for Black-and-White Output 92 Four-Color Grays 92 Creating Multitones 93 The Photoshop Duotone Method 93 Four-Color Multitones 93 Multitone Design Guidelines 96 О Tonal Cprrection for Output 97 Image Correction Principles 98 What's the Goal? Or, Why Your Vacation Photos Don't Live Up to Your Memories 98 More Than One Path to the Same Destination 98 Garbage In, Gems Out 99 Correct in the Optimum Color Space 99 Correction by the Numbers 99 Make Corrections Globally 100 Use Curves to Make Most Adjustments 100 Sound Image Correction Practices 101 Tonal Range Basics 101 Identifying Tonal Character 103 Correcting Exposure Problems 104 Print Output and Tonal Compression 105 Adjusting Highlight Values 106 Using Preset Curves 107 Finding the Highlight 107 Specular Highlights 108 Images with No True Highlights 108 When Highlights Contain a Color Cast 109 Adjusting Shadow Values 109 Setting the Shadow Value 110 Images with No True Shadows 111 Basic Midtone Adjustments 111 Restoring Contrast Based on Tonal Character 111 Curve-Based Dot Gain Compensation 111 Tone into Color 112 Ш Balancing and Correcting Color m The Ground Rules 114 Neutralizing Color Casts 115 Detecting Color Casts 115 Neutralizing Casts 117 Color Casts: Summing Up 120 Enhancing Important Colors and Subjects 121 Boosting Contrast and Detail 122 Intensifying Saturation 122 Controlling Brilliance and Depth 122 Making the Most of the "Underdog" Color 126 Matching Colors 128 Ш Resolution and Sizing for Print Media m Types of Resolution 129 Input Resolution 130 Output Resolution 130 Printer Resolution 130 Other Faces of Resolution 132 How Much Data Do You Need? 133 Output Resolution and the "Halftoning Factor" 134 Output Resolution for Continuous-Tone Printers 135 Output Resolution for FM Screening 135 Output Resolution for Bitmaps 135

5 vi Resizing and Resampling Images 136 Sizing Strategies 136 Size Before You Sharpen 138 Multiple-Use Images 139 ЕЕ Sharpening and Special-Case Adjustments w Sharpening Strategies 141 Simple Contrast-Enhancing Techniques 142 Edge-Sharpening and Noise Filters 142 Unsharp Masking (USM) Filters 143 Sharpening the Black Channel Only 145 Sharpening in LAB Color 145 Toward "Sharper" Color 146 Descreening Previously Printed Images 146 Preventing Content Moire 148 Trapping Raster Images 148 Choosing a File Format 150 Flavors of TIFF 150 EPS Files 150 Communicate, Communicate 152 Appendix A: An Image-Output Checklist 153 Index 155