Klaus Goelker. GIMP 2.8 for Photographers. Image Editing with Open Source Software. rocky

Transcription

1 Klaus Goelker GIMP 2.8 for Photographers Image Editing with Open Source Software rocky

2 Table of Contents Chapter 1 Basics Preface Introduction Using GIMP 2.8 About This Book About GIMP Overview of the Most Important Improvements and Changes in GIMP Introduction to Digital image Editing Characteristics of Pixel Images Resolution Screen Colors Color Models and GEGL, the New Graphics Library Important File Formats for Practical Work Loading and Managing Digital Photos on the Computer Using the Operating System's File Management Tools to Import Images from a Camera Using Wizards to Import Images Using the Operating System's File Management to Organize Photo Collections Helpers: Image Management Programs for Windows, Linux, and Mac OS X Converting Camera RAW Image Formats under Windows, Mac OS X, and Linux: Freeware and Plug-Ins 27

3 r A B 1. r 0 I 10 N I (: n i s 1.5 Get GIMP Running Where Can I Get GIMP? Installing GIMP and Plug-Ins Is GIMP Insecure? Some Comments and Tips The GIMP'S Program Windows Using and Customizing the Program Interface Important Menus Real Help GIMP'S Help Function 54 Chapter 2 Using GIMP: Correcting and Touching Up Your Images Working with GIMP: Image Adjustment and Retouching Opening, Setting, and Storing an Image: The Steps Opening an Image The Image Window Your Workspace Rotating an Image by Fixed Values Changing the Image View Size (Zooming) Cropping (Clipping) an Image Setting the Image Size and Resolution Scaling the Print Size of Images Converting Resolution and Size Saving Your Image Before Printing Calibrating Monitors and Color Management Printing Images 86

4 TAB! L OF CONTENTS 2.2 Working with Scanned Images Prerequisites for Scanning How Scanners Work Problems When Scanning Printed Originals the Moire Effect Calculations to Consider before Scanning Scanning and Editing an Image Typical Errors in Scanned Images Setting the Image and Determining the Angle Measuring Rotating an image Using the Rotate Tool Cropping an Image the Crop Tool Using the Gaussian Blur Filter to Remove the Moire Effect Adjusting and Improving Color and Exposure Levels (Tonality Correction) Curves Adjusting Hue and Saturation Overview of the Functions in the Image > Colors Menu Saving an Image in Compressed Format (JPG/JPEG) for the Internet Touchup Work 1 Color Casts What Is Touchup Work? Color Correction Options Using the Levels Function to Correct Color Casts A Second Method of Removing Color Casts Color Balance 125

5 2.5 Touchup Work 2 Removing Spots, Dust, and Scratches Why You Need Smooth Brushes the Clone Tool Creating New Brush Pointers in GIMP and Importing Adobe Photoshop Brushes Selecting the CloneTool Options Using the CloneTool for Touchup Work The Healing Tool Performing Maqic Editinq Photographs with J -J -J s Graphic Filters Sharpening Images and Image Elements Noise Reduction and "Smoothening" Images Simulating Film Grain Covering Up Blemishes with Noise and Pixels 148 Chapter 3 Using Masks and Layers Painting, Filling, and Color Tools Introduction to Masks and Selections Overview of Select Tools in the Toolbox Tips for Handling Select Tools The Select Menu TheEditMenu Touchup Work 3 Removing Red Eyes Avoiding Red Eye Using the Flash Correctly Eliminating the Red-Eye Effect 164

6 Introduction to Working with Layers The Layers Dialog The Context Menu in the Layers Dialog Background or Layer with an Alpha Channel Working with Several Images Inserting Layers from Another Image 173 Touchup Work 4 Correcting Overexposed or Underexposed linages I/'! The Mode Settings in the Layers Dialog Editing Overexposed Images Editing Underexposed Images 176 Touchup Work 5- -Using Perspective Correction to Remove Converging Verticals 17? Trying to Avoid Converging Verticals When Taking Shots Steps Involved and Description of Work Removing Converging Verticals from an Image Removing Lens Distortion, Making Perspective Corrections, and Reducing Vignetting The Perspective Clone Tool 184 Touchup Work 6- Freshening Up <i "Dull Sky" 1S Steps Involved and Description of Work Step 1: Selecting an Area by Color, Deleting It, and Replacing It with Color Fill Step 2: Creating and Positioning an Image Object on a New Layer Step 3: Creating a Multicolor Sky the Blend Tool Step 4: Adding a New Object or Layer (Sky) to an Image 206

7 I A B L E Of CONTENTS 3.7 Typing in GIMP -Adding Text to an Image Introduction to Fonts Typing in GIMP the Text Tool Typing Text and Defining the Text Attributes Creating Three-Dimensional Text and a Drop Shadow Creating Your Own Image Frames and Vignettes Single-Color Image Frames Creating a Frame with a Pattern Vignettes for Images Creating and Editing linage Elements Lighting Effects and Shadow Layers Overview of Step 1 Creating a New Image and New Image Objects Creating a New Image Transforming a Selection Using the Paintbrush Tool to Create Lighting and Shadow Effects: Glazing Technique Inserting and Duplicating Layers and Layer Groups Changing the Color of an Image Object the Hue-Saturation Function Extracting Image Objects with Select and Masking Tools The Polygon Lasso and Intelligent Scissors Select Tools Extracting a Wine Glass with the Polygon Lasso Creating a Selection with the Polygon Lasso, Following a Contour 235

8 I A 8 I E OF C 0 N f E NIS 3.11 Using the Paths Tool to Create Vector Forms and Selections Using Filters for Light Effects Copying a Wine Glass and Creating a Drop Shadow Overview of the Steps Involved Creating and Editing a Path^the Design Editing Mode The Path Editing Mode The Paths Dialog Transforming Paths the Shear Tool Creating Lighting Effects with Brushes and Filters Paths and Text Aligning Images the Alignment Tool The Cage Transform Tool Cross-Fading with Masks and Selections Cross-Fading Part 1 Cross-Fading Two Images with Two Different Motifs The Canvas and Canvas Size Cross-Fading Part 2 Assembling Panoramic Images Programs for Creating Panoramas Automatically Composites -Using Masks and Selections to Cut and Paste Image Objects Copying an Image Object with the Help of a Selection and Inserting It into Another Image the Procedure The Mode Options in the Layers Dialog The Foreground Select Tool Extracting Images Automatically Drawing a Mask Using Paint Tools with Various Edge Attributes 278

9 3.16 GIMP and HDR What Is HDR? HDR Software Cross-Fading Part 3 Merging images into One Pseudo HDR A Short Introduction to Working with Layer Masks 289 Chapter 4 Working with Black-and-White and Color Images Converting Color images Partly or Entirely into Grayscale Images Hints for Working in Grayscale and RGB Modes Removing Color Partly or Entirely Developing Black-and-White Images with the Channel Mixer The Graphical Library GEGL Developing Black-and-White Images with GEGL Operations Converting Images into Black-and-White Graphics Graphic Effects with Gray Levels an Example Partial Desaturation Infrared Effects Touching Up Black-and-White Images- Levels, Brightness, Contrast ExtractingHai r fro rn t h e Bac kg rou n d a Tr i c k y Ta s k The Threshold Function Using the Threshold Function to Extract Hair^theTask Using Channels to Extract an Object from the Background..315

10 > X TAB! E OF CONTENTS 4.4 Coloring Grayscale Images Using the Colorize Function to Color an Image Using the Levels Function to Color an Image Using the Curves Function to Color an Image with One or More Colors Using the Colorify Filter to Color an Image Using Transparency and the Colorize Filter to Color Image Areas by Brightness Using the Sample Colorize Function to Color an Image Using Filters to Color and Bleach an Image "Hand-Colored" Images from Black-and-White Photos Features and Elements of UFRaw's Main Window RawTherapee for Developing RAW Images Using the PDF Format to Share Print Layouts Opening PDF Files in GIMP Using GIMP to Create PDFs Free Alternative PDF Creation and Viewing Software PSD Files Opening Adobe PSD Files in GIMP PSD Files Exported from GIMP and Opened in Photoshop 369

11 Appendix 371 A.1 The IWarp Filter a Closing Comment 372 A.2 So Far, So Good How to Proceed from Here: Tips and References 373 A3 The Future of GIMP.374 A.3.1 Downloading and Installing Developer's Versions of GIMP 374 A.4 Thank You! 375 A.5 Further Reading on GIMP: References 375 A.6 What's on the DVD 376 A.7 Native GIMP File Formats 378 Index 381