A Book on Photography

13th Edition, September 2020

By David Salomon. A free eBook with 773 Figures. xxiii+1325 pages, available here.

From the Preface

Goal of the Book

The fact that current compact cameras produce good (or at least, adequate) pictures in most photographic situations is at the root of this book. The main aim of the book is to show how such a camera can be operated and its controls tweaked to cover many different photographic conditions and requirements. (To put it another way, the chief goal of the book is to convince the reader that large, expensive cameras are absolutely necessary in only rare situations.) In addition, this book discusses the science of photography--including topics such as optics, lenses, colors, human vision, image sensors, exposure, and white balance--and explains the main types of cameras. Mathematics is used whenever it helps to illustrate a term or a concept, because it is my belief that the use of mathematics may greatly illuminate many subjects. However, the mathematical background required is minimal and is limited to angles, similar triangles, and basic algebraic manipulations.

Organization and Features

Chapter 1 concentrates on the basic concepts behind photography, namely light, the eye, color, and geometrical optics. The latter topic includes refraction, prisms, and lenses.

Chapter 2 explains how a basic digital camera works and follows with a discussion of basic photographic terms such as exposure, f-stop, depth of field, shutter speed, ISO, white balance, and auto-focus.

Chapter 3 is devoted to the principal types of digital cameras. This includes digital- single-lens-reflex (DSLR), twin-lens-reflex (TLR), digital-single-lens-mirrorless (DSLM and MILC), rangefinder, bridge, micro four thirds (MFT) (Section 3.9), compact (point- and-shoot), and special types of cameras such as ultraviolet, infrared, 360-degree panoramic cameras, and 3D cameras.

Chapter 4 describes two compact cameras and shows how to use them in many practical situations. The goal of the chapter is to convince the reader that the compact cameras currently available can, especially with the help of extra software, offer serious competition to their more sophisticated (and also bigger, heavier, and more expensive) cousins the DSLRs and MILCs. The reader will learn, among others, how to obtain a shallow or a large depth-of-field (Section 2.6) by controlling the aperture size and how to handle situations with high dynamic range. (HDR, Section 4.6, is a measure of the lightest to the darkest tones in an image. HDR is important where the subject had very bright and very dark parts and we want all their details to appear in the final image.) How to shoot when motion is detected (Section 4.10), how to shoot a time-lapse sequence of images (Section 4.3), and how to mount detachable wide-angle and telephoto lenses in addition to the original, non-interchangeable lens of the camera. The chapter also shows how many Canon compact cameras, even old models, can be given a new life and coerced to perform "miracles" such as the following: (1) Work in shutter-priority and aperture priority modes, (2) output raw image files in addition to the standard JPEG, (3) work with very fast (in some cases up to 1/8000 s) and very slow (up to 64 s) shutter speeds, (4) display RGB color histograms, (5) detect motion, (6) take a group of exposure-bracketing photos, and (7) use the built-in timer to reduce camera shake and vibrations.

Chapter 5 is a detailed discussion of the important concept of high dynamic range (HDR). The term "dynamic range" is defined, the HDR problem is explained, and it is shown how to shoot a sequence of bracketed HDR images either handheld or with a tripod. The chapter continues with descriptions of the two main approaches to HDR, namely exposure fusion and tone mapping.

Chapter 6 is an extensive summary of the history of photography. Individual sections are devoted to the most important milestones in the development of photography. There are short biographies of eminent photographers, a list of historically-important photographs, and a detailed timeline of photography.

Chapter 7 covers several topics and techniques used in the important field of computational photography. Most of this chapter is devoted to traditional methods of image manipulation and processing, but it also includes descriptions of several new, "magical" algorithms that produce unexpected (and often unbelievable) results.

Chapter 8 is about image composition. It describes the important methods for composing images, and illustrates each with examples.

Appendix A lists and explains the controls found on two modern cameras.

Appendix B is a glossary of photographic terms.

Appendix C is a list of the important features buyers should look for in compact
cameras. This material is especially relevant to those who are looking to purchase such a camera.

Appendix D discusses legal issues that should interest any photographer or would-be photographer.

The remaining appendixes are for mathematically-savvy readers who would like to understand the details of the JPEG algorithm, how a lens is shaped, and what exactly is a pixel.

Appendix E tries to explain the basic steps of the JPEG algorithm in a non-mathematical language. This material is intended for readers who are interested in more than just using a camera and obtaining great pictures. This material is followed by a description of the TIFF file format.

Appendix F employs several mathematical techniques and approaches to analyze the behavior of spherical lenses and derive the equation of an aspherical lens.

Finally, Appendix G discusses pixels, their meaning and how to interpolate them.

Target Audiences

I planned this book for those interested in digital photography and cameras in general, who are not afraid to learn and understand technical topics. The book discusses many technical subjects in depth and it does not hesitate to use mathematics when needed. On the other hand, there isn’t much about the important topic of image composition and there aren’t many large, beautiful photos. In this respect, the book is different from the many other books on photography available today.

A disclaimer. As new editions of this book come out, the book gets not only bigger, but more inclusive. More and more topics, concepts, and techniques are described, but it is important to realize that the book is not complete and never will be. Because of the nature of digital photography (it is controlled by software, which makes it possible to add features without adding hardware) and the wide interest in photography, new cameras, lenses, accessories, and software appear all the time. Thus, if you cannot find a favorite topic in the book, simply write to me and you may find it in a future edition.


I would like to thank Nelson Beebe for many suggestions, improvements, and error corrections. His help has been invaluable.

I welcome any comments, suggestions and corrections. They should be emailed to [email protected]. An errata list and other information may later be added to this website.


Any comments, suggestions, and corrections are welcome and should be emailed to the author at [email protected] However, if you notice something missing, consider the following quote (from Mark Twain) “A successful book is not made of what is in it, but of what is left out of it.”

Book Cover

Table of Contents

Preface vii

Introduction 1

1 Light and Optics 71

1.1 Light and Color 71
1.2 Color and the Eye 73
1.3 Color and Human Vision 74
1.4 Color Spaces 86
1.5 Color () Grayscale Conversion 95
1.6 Luminance 102
1.7 Human Vision vs. a Camera 103
1.8 Optics 105
1.9 Mirrors in Photography 109
1.10 Refraction 116
1.11 The Pentaprism 122
1.12 Lenses 123
1.13 Compound Lenses 131
1.14 Zooming and Zoom Lenses 133
1.15 Macro Lenses 140
1.16 Fisheye Lenses 142
1.17 Fisheye Projection 144
1.18 Poor Man's Fisheye 148
1.19 Tilt-Shift Lenses 149
1.20 Anti-Reflection Coatings 156
1.21 Lens Aberrations 158
1.22 Printing Images 161
1.23 Halftoning 179
1.24 Dithering 180
1.25 Printers and the Longevity of Prints 190

2 Digital Cameras 201

2.1 Basic Components 201
2.2 The Viewfinder and Camera Types 203
2.3 The Shutter 209
2.4 F-Stops and Lens Speed 234
2.5 Aperture 253
2.6 Depth-of-Field 257
2.7 Depth-of-Field Equations 271
2.8 ISO and Image Noise 287
2.9 Exposure Review 299
2.10 Exposure Values 304
2.11 Image Sensors 309
2.12 White Balance 350
2.13 Output Files 353
2.14 Focusing, Manual and Automatic 362
2.15 Light Metering 388
2.16 Exposure Compensation 392
2.17 The Histogram 394
2.18 Lenses 405
2.19 Macro Photography 415
2.20 Accessories 422
2.21 ND Filters and Long Exposures 433

3 Camera Types 447

3.1 Pinhole Cameras 447
3.2 Single Lens Reflex 450
3.3 Single Lens Translucent 455
3.4 Twin Lens Reflex 456
3.5 Rangefinder 458
3.6 View Cameras 461
3.7 Mirrorless (MILC) 464
3.8 Bridge Cameras 468
3.9 Micro Four Thirds (MFT) 469
3.10 Compact Cameras 484
3.11 Action Cameras 490
3.12 Specialty Cameras 492
3.13 Infrared Cameras 500
3.14 Night Vision Cameras 502
3.15 3D Cameras 505
3.16 Panoramic Cameras 509
3.17 Miniature Cameras 520
3.18 Dash Cameras 521
3.19 Security Cameras 528
3.20 Drone Cameras 531
3.21 The L16 Multi-Aperture Camera 535

4 Compact Cameras 547

4.1 CHDK 548
4.2 Overrides in CHDK 559
4.3 Time-Lapse and CHDK 562
4.4 CHDK Intervalometer Script Examples 569
4.5 The Intervalometer as a Script 572
4.6 HDR 573
4.7 HDR with CHDK; No Script 576
4.8 HDR Algorithms 579
4.9 CHDK Motion Detection 586
4.10 USB Remote 588
4.11 Zeikos lenses 591

5 High Dynamic Range 597

5.1 Definitions and Units of HDR 598
5.2 The HDR Problem 601
5.3 Shooting HDR Bracketed Images 606
5.4 Exposure Fusion 612
5.5 HDR Radiance Maps 615
5.6 Tone Mapping 618
5.7 HDR Time-Lapse 623
5.8 HDR Software 625
5.9 Floating-Point Numbers 626

6 History of Photography 631

6.1 The Main Question 632
6.2 Early Attempts 635
6.3 Plates, Wet and Dry 672
6.4 George Eastman and Kodak 684
6.5 Leica and 35 mm Photography 696
6.6 SLRs, Nikon, Canon, and Pentax 701
6.7 The Digital Revolution 720
6.8 History of Smartphone Cameras 723
6.9 Distinguished Photographers 731
6.10 First-in-Class Photographs 791
6.11 History of Photography Timeline 806

7 Computational Photography 827

7.1 Point Operations 831
7.2 Image Blending 839
7.3 Filters 842
7.4 Edge Detection 850
7.5 The Hough Transform 858
7.6 Edge Sharpening 862
7.7 Morphological Filters 864
7.8 Discrete Convolution 868
7.9 Dual Photography 876
7.10 Light Field (Plenoptic) Cameras 881
7.11 The Discrete Fourier Transform 894
7.12 Coded Aperture 905
7.13 HDR+ and its Relatives 912
7.14 Face Detection 921

8 Image Composition 927

8.1 The Basics 927
8.2 Rules of Image Composition 932
8.3 Ideas for Great Photographs 938
8.4 Natural Lighting and Photography 1005
8.5 The Main Compositional Elements 1029
8.6 The Direction of the Light 1046
8.7 Fill The Frame 1050
8.8 The Rule of Thirds (R.O.T.) 1050
8.9 Locating Good Scenes 1053
8.10 Building Blocks of Good Scenes 1056
8.11 Snapseed 1066

A Camera Controls 1083

A.1 Canon EOS 5D Controls 1084
A.2 Panasonic DMC-G7 Controls 1090
A.3 Camera Menus 1095

B Glossary of Photographic Terms 1101

C Compact Cameras Feature Guide 1119

C.1 Good and Bad 1120
C.2 Main Features 1120
C.3 Advanced Features 1128

D Legal Issues 1131

D.1 Public and Private Places 1132
D.2 Privacy Issues 1134
D.3 Restrictions on Subjects 1136
D.4 Protect Your Work 1142

E JPEG and TIFF 1147

E.1 Image Redundancy 1147
E.2 Image Types 1149
E.3 Summary of JPEG 1150
E.4 Image Transforms 1154
E.5 TIFF 1165
E.6 Facsimile Compression 1167
E.7 PackBits Compression 1171

F The Shape of a Lens 1173

F.1 Spherical Lenses 1175
F.2 Aspherical Lenses 1181

G Pixels 1197

G.1 Point Samples 1197
G.2 Real Optical Devices 1200
G.3 Pixel Interpolation 1201
G.4 Replicating Rows/Cols 1203
G.5 Replicating Pixels 1203
G.6 More About Image Scaling 1205
G.7 Bilinear Interpolation 1208
G.8 Bicubic Interpolation 1209
G.9 The Sampling Theorem 1215

References 1223
Answers to Exercises 1235
Index 1285


What I have to say about this book can be found inside the book. --Albert Einstein

Last Updated 16 Sept 2020