D DD DDD DDDDon.com DDDD Basic Photography in 180 Days Book IV - Lens Editor: Ramon F. aeroramon.com Contents 1 Day 1 1 1.1 History of photographic lens design .................................. 1 1.1.1 Early photographic camera lenses ............................... 1 1.1.2 Meniscus or 'landscape' lens ................................. 3 1.1.3 Petzval Portrait lens ...................................... 3 1.1.4 Overcoming optical aberrations ................................ 4 1.1.5 Aperture stops ........................................ 4 1.1.6 Telephoto lens ......................................... 7 1.1.7 Anastigmat lens ........................................ 8 1.1.8 Cooke Triplet ......................................... 9 1.1.9 Tessar ............................................. 9 1.1.10 Ernostar and Sonnar ..................................... 9 1.1.11 Asymmetric double Gauss .................................. 11 1.1.12 Anti-reflection coating .................................... 12 1.1.13 Retrofocus wide-angle lens .................................. 14 1.1.14 Fisheye lens .......................................... 16 1.1.15 Macro lens .......................................... 16 1.1.16 Supplementary lens ...................................... 16 1.1.17 Zoom lens ........................................... 19 1.1.18 Rise of Japanese optical industry ............................... 21 1.1.19 Catadioptric “mirror” lens .................................. 21 1.1.20 Movable element prime lens ................................. 22 1.1.21 Bokeh ............................................. 22 1.1.22 Improving standards of quality ................................ 23 1.1.23 Inexpensive asphere ...................................... 23 1.1.24 Autofocus lens ........................................ 23 1.1.25 Image-stabilized lens ..................................... 24 1.1.26 Diffractive optic lens ..................................... 24 1.1.27 Lenses in the digital era .................................... 24 1.1.28 References .......................................... 25 1.1.29 Further reading ........................................ 34 2 Day 2 48 i ii CONTENTS 2.1 Camera lens .............................................. 48 2.1.1 Theory of operation ...................................... 49 2.1.2 Construction ......................................... 49 2.1.3 Aperture and focal length ................................... 50 2.1.4 Number of elements ..................................... 51 2.1.5 Lens mounts ......................................... 51 2.1.6 Types of lens ......................................... 52 2.1.7 History and technical development of photographic camera lenses .............. 53 2.1.8 Lens designs .......................................... 53 2.1.9 See also ............................................ 54 2.1.10 Notes ............................................. 54 2.1.11 References .......................................... 54 2.1.12 External links ......................................... 55 3 Day 3 59 3.1 Photographic lens design ....................................... 59 3.1.1 Design ............................................. 59 3.1.2 Types of lenses ........................................ 62 3.1.3 History ............................................ 65 3.1.4 See also ............................................ 67 3.1.5 References .......................................... 67 4 Day 4 69 4.1 Aperture ................................................ 69 4.1.1 Application .......................................... 69 4.1.2 In photography ........................................ 70 4.1.3 Equivalent aperture range ................................... 73 4.1.4 In scanning or sampling .................................... 73 4.1.5 See also ............................................ 74 4.1.6 References .......................................... 74 4.2 Diaphragm (optics) .......................................... 80 4.2.1 Iris diaphragms versus other types .............................. 81 4.2.2 History ............................................ 82 4.2.3 See also ............................................ 84 4.2.4 References .......................................... 84 5 Day 5 85 5.1 Normal lens .............................................. 85 5.1.1 Perspective effects of short or long focal-length lenses .................... 85 5.1.2 'Normal' lenses vary for different formats .......................... 85 5.1.3 Typical normal focal lengths for different formats ...................... 85 5.1.4 References .......................................... 87 CONTENTS iii 5.2 Prime lens ............................................... 87 5.2.1 As alternative to zoom lens .................................. 88 5.2.2 Traditional meaning as primary lens ............................. 88 5.2.3 Popular focal lengths ..................................... 89 5.2.4 Specialist lenses ....................................... 90 5.2.5 References .......................................... 90 5.2.6 External links ......................................... 90 5.3 Zoom lens ............................................... 91 5.3.1 Characteristics ........................................ 91 5.3.2 History ............................................ 92 5.3.3 Design ............................................. 93 5.3.4 Varifocal lens ......................................... 97 5.3.5 See also ............................................ 98 5.3.6 References .......................................... 98 5.3.7 External links ......................................... 98 6 Day 6 99 6.1 Telephoto lens ............................................. 99 6.1.1 Construction ......................................... 99 6.1.2 History ............................................ 101 6.1.3 See also ............................................ 103 6.1.4 References .......................................... 103 6.1.5 External links ......................................... 104 6.2 Teleconverter ............................................. 104 6.2.1 Function ............................................ 105 6.2.2 See also ............................................ 107 6.2.3 References .......................................... 107 7 Day 7 108 7.1 Long-focus lens ............................................ 108 7.1.1 Effects of long-focus lenses .................................. 108 7.1.2 Telescopes as long-focus lenses ................................ 110 7.1.3 See also ............................................ 110 7.1.4 References .......................................... 110 7.2 Close-up filter ............................................. 111 7.2.1 See also ............................................ 114 7.2.2 External links ......................................... 114 7.3 Macro photography .......................................... 114 7.3.1 History ............................................ 115 7.3.2 Equipment and techniques .................................. 115 7.3.3 35 mm equivalent magnification ............................... 120 7.3.4 Technical considerations ................................... 121 iv CONTENTS 7.3.5 See also ............................................ 124 7.3.6 References .......................................... 124 7.3.7 External links ......................................... 125 8 Day 8 126 8.1 Wide-angle lens ............................................ 126 8.1.1 Angle of view ........................................ 127 8.1.2 Characteristics ........................................ 127 8.1.3 Wide-angle lenses for 35 mm format ............................. 127 8.1.4 Digital camera considerations ................................ 127 8.1.5 Construction ......................................... 128 8.1.6 See also ............................................ 128 8.1.7 References .......................................... 128 8.1.8 Notes ............................................. 129 8.1.9 External links ......................................... 129 8.2 Fisheye lens .............................................. 134 8.2.1 Uses in photography ..................................... 135 8.2.2 Sample images ........................................ 139 8.2.3 Other applications ....................................... 140 8.2.4 Mapping function ....................................... 141 8.2.5 See also ............................................ 143 8.2.6 Notes ............................................. 143 8.2.7 References .......................................... 143 8.2.8 External links ......................................... 144 9 Day 9 145 9.1 Optical coating ............................................ 145 9.1.1 Types of coating ....................................... 145 9.1.2 Current market and forecast ................................. 150 9.1.3 Sources ............................................ 150 9.1.4 References .......................................... 150 9.1.5 See also ............................................ 150 9.1.6 External links ......................................... 150 9.2 Optical filter .............................................. 150 9.2.1 Absorptive .......................................... 152 9.2.2 Dichroic filter ......................................... 152 9.2.3 Monochromatic ........................................ 152 9.2.4 Infrared ............................................ 152 9.2.5 Ultraviolet ........................................... 153 9.2.6 Neutral density