A Book on Photography

8th Edition, January 2016

By David Salomon. A free eBook with 360 Figures. xiii+760 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

There are six chapters and nine appendixes.

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, compact (point-and-shoot), and special types of cameras such as ultraviolet, infrared, 360 panoramic cameras, miniature and spy cameras, and 3D cameras.

Chapter 4 describes two compact cameras and shows how to use them in many practical situations. The intent here is to convince the reader that the compact cameras currently available are not significantly inferior 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 4.11), 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 a wide survey of the history of photography. It also includes biographies of several eminent photographers and a detailed timeline of photography.

Appendix A describes the many controls found on a modern DSLR.

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 last two appendixes are for mathematically-savvy readers who would like to know the details of the JPEG algorithm and how a lens is shaped.

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.

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

Appendix G describes a typical algorithm used by cameras to detect faces.

Appendix H is a short introduction to image processing methods.

Appendix I is devoted to pixels, their history, their properties, and their meaning.

Target Audiences

I planned this book with two audiences in mind, those interested in digital photography and cameras in general and those interested in getting the maximum out of their compact cameras. The former audience would be interested in the first part of the book, especially the material on optics and concepts of digital cameras. The latter audience would be interested in the material on compact cameras and what they can achieve. The appendixes should be of interest to all readers.


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.

Book Cover

Table of Contents

Preface vii

Introduction 1

1 Light and Optics 39

1.1 Light and Color 39
1.2 Color and the Eye 41
1.3 Color and Human Vision 42
1.4 Color Spaces 50
1.5 Luminance 55
1.6 Optics 57
1.7 Mirrors in Photography 58
1.8 Refraction 64
1.9 The Pentaprism 68
1.10 Lenses 69
1.11 Compound Lenses 73
1.12 Zoom Lenses 75
1.13 Macro Lenses 76
1.14 Fisheye Lenses 77
1.15 Fisheye Projection 80
1.16 Poor Man's Fisheye 84
1.17 Anti-Reflection Coatings 84
1.18 Lens Aberrations 86
1.19 Printing Resolution, ppi and dpi 89

2 Digital Cameras 95

2.1 Basic Components 95
2.2 The Viewfinder and Camera Types 97
2.3 The Shutter 101
2.4 F-Stops and Lens Speed 116
2.5 Aperture 131
2.6 Depth-of-Field 136
2.7 Depth-of-Field Equations 147
2.8 ISO and Image Noise 163
2.9 Exposure Review 169
2.10 Image Sensors 173
2.11 White Balance 201
2.12 Output Files 205
2.13 Focusing, Manual and Automatic 210
2.14 Light Metering 227
2.15 Exposure Compensation 230
2.16 The Histogram 234
2.17 Lenses 242
2.18 Macro Photography 251
2.19 Tripods and Monopods 252
2.20 A Shock 255

3 Camera Types 257

3.1 Pinhole Cameras 257
3.2 Single Lens Reflex 258
3.3 Single Lens Translucent 263
3.4 Twin Lens Reflex 264
3.5 Rangefinder 265
3.6 View Cameras 267
3.7 Mirrorless (MILC) 270
3.8 Bridge Cameras 272
3.9 Compact Cameras 274
3.10 Specialty Cameras 279
3.11 Infrared Cameras 284
3.12 3D Cameras 287
3.13 Panoramic Cameras 292
3.14 Miniature Cameras 296
3.15 The L16 Multi-Aperture Camera 297

4 Compact Cameras 309

4.1 CHDK 310
4.2 Overrides in CHDK 321
4.3 Time-Lapse and CHDK 324
4.4 CHDK Intervalometer Script Examples 329
4.5 The Intervalometer as a Script 332
4.6 HDR 333
4.7 HDR with CHDK No Script 336
4.8 HDR with CHDK Scripts 337
4.9 HDR of a Single Photograph 339
4.10 HDR Algorithms 340
4.11 CHDK Motion Detection 346
4.12 USB Remote 347
4.13 Zeikos lenses 351

5 High Dynamic Range 357

5.1 Definitions and Units of HDR 358
5.2 The HDR Problem 359
5.3 Shooting HDR Bracketed Images 363
5.4 Exposure Fusion 371
5.5 HDR Radiance Maps 374
5.6 Tone Mapping 377
5.7 HDR Software 381
5.8 Floating-Point Numbers 383

6 History of Photography 387

6.1 Early Attempts 388
6.2 Plates, Wet and Dry 421
6.3 George Eastman and Kodak 433
6.4 Leica and 35 mm Photography 441
6.5 SLRs, Nikon, Canon, and Pentax 445
6.6 The Digital Revolution 461
6.7 Distinguished Photographers 464
6.8 History of Photography Timeline 514

A DSLRs Controls 533

B Glossary of Photographic Terms 541

C Compact Cameras Feature Guide 559

C.1 Good and Bad 560
C.2 Main Features 560
C.3 Advanced Features 568

D Legal Issues 571

D.1 Public and Private Places 572
D.2 Privacy Issues 574
D.3 Restrictions on Subjects 576
D.4 Protect Your Work 581

E The JPEG Algorithm 585

E.1 Image Redundancy 585
E.2 Image Types 587
E.3 Summary of JPEG 588
E.4 Image Transforms 590

F The Shape of a Lens 601

F.1 Spherical Lenses 601
F.2 Aspherical Lenses 608

G Face Detection 623

H Image Processing Methods 629

H.1 Point Operations 630
H.2 Filters 638
H.3 Edge Detection 646
H.4 The Hough Transform 654
H.5 Edge Sharpening 658
H.6 Morphological Filters 660
H.7 Convolution 664

I Pixels 673

I.1 Point Samples 673
I.2 Real Optical Devices 675
I.3 Pixel Interpolation 676
I.4 Image Stretching 678
I.5 Replicating Pixels 678
I.6 More About Image Scaling 680
I.7 Bilinear Interpolation 683
I.8 Bicubic Interpolation 684
I.9 The Sampling Theorem 690

References 697

Answers to Exercises 707

Index 735


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

Last Updated 11 Jan 2016