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Book II Optics V VV VVV VVVVon.com VVVV Basic Photography in 180 Days Book II - Optics Editor: Ramon F. aeroramon.com Contents 1 Day 1 1 1.1 History of optics ............................................ 1 1.1.1 Early history of optics ..................................... 1 1.1.2 Optics and vision in the Islamic world ............................ 3 1.1.3 Optics in medieval Europe .................................. 3 1.1.4 Renaissance and early modern optics ............................. 6 1.1.5 Lenses and lensmaking .................................... 7 1.1.6 Quantum optics ........................................ 8 1.1.7 See also ............................................ 8 1.1.8 Notes ............................................. 8 1.1.9 References .......................................... 10 2 Day 2 11 2.1 Geometrical optics ........................................... 11 2.1.1 Explanation .......................................... 11 2.1.2 Reflection ........................................... 11 2.1.3 Refraction ........................................... 12 2.1.4 Underlying mathematics ................................... 16 2.1.5 See also ............................................ 18 2.1.6 References .......................................... 18 2.1.7 Further reading ........................................ 19 2.1.8 External links ......................................... 19 3 Day 3 20 3.1 Optics ................................................. 20 3.1.1 History ............................................ 20 3.1.2 Classical optics ........................................ 26 3.1.3 Modern optics ......................................... 38 3.1.4 Applications .......................................... 39 3.1.5 See also ............................................ 42 3.1.6 References .......................................... 42 3.1.7 External links ......................................... 46 3.2 Optical instrument ........................................... 57 i ii CONTENTS 3.2.1 Image enhancement ...................................... 57 3.2.2 Analysis ............................................ 57 3.2.3 Other optical devices ..................................... 57 3.2.4 See also ............................................ 57 3.2.5 References .......................................... 57 3.2.6 External links ......................................... 58 4 Day 4 59 4.1 Lens (optics) .............................................. 59 4.1.1 History ............................................ 60 4.1.2 Construction of simple lenses ................................. 60 4.1.3 Imaging properties ...................................... 62 4.1.4 Aberrations .......................................... 64 4.1.5 Compound lenses ....................................... 66 4.1.6 Other types .......................................... 67 4.1.7 Uses .............................................. 67 4.1.8 See also ............................................ 68 4.1.9 References .......................................... 68 4.1.10 Bibliography ......................................... 70 4.1.11 External links ......................................... 70 5 Day 5 76 5.1 Focus (optics) ............................................. 76 5.1.1 See also ............................................ 77 5.1.2 References .......................................... 78 5.2 Cardinal point (optics) ......................................... 78 5.2.1 Explanation .......................................... 79 5.2.2 Modeling optical systems as mathematical transformations .................. 80 5.2.3 See also ............................................ 81 5.2.4 Notes and references ..................................... 81 5.2.5 External links ......................................... 81 6 Day 6 87 6.1 Hyperfocal distance .......................................... 87 6.1.1 Acceptable sharpness ..................................... 87 6.1.2 Formulae ........................................... 87 6.1.3 Example ............................................ 88 6.1.4 Mathematical phenomenon .................................. 90 6.1.5 History ............................................ 90 6.1.6 See also ............................................ 93 6.1.7 References .......................................... 93 6.1.8 External links ......................................... 93 CONTENTS iii 7 Day 7 95 7.1 Angle of view ............................................. 95 7.1.1 Calculating a camera’s angle of view ............................. 96 7.1.2 Measuring a camera’s field of view .............................. 100 7.1.3 Lens types and effects .................................... 101 7.1.4 Common lens angles of view ................................. 103 7.1.5 Sensor size effects (“crop factor”) .............................. 104 7.1.6 Cinematography and video gaming .............................. 104 7.1.7 References and notes ..................................... 104 7.1.8 See also ............................................ 105 7.1.9 External links ......................................... 105 7.2 Field of view .............................................. 107 7.2.1 Humans and animals ..................................... 108 7.2.2 Conversions ......................................... 109 7.2.3 Machine vision ........................................ 109 7.2.4 Remote sensing ........................................ 109 7.2.5 Astronomy .......................................... 109 7.2.6 Photography ......................................... 110 7.2.7 Video games ......................................... 110 7.2.8 See also ............................................ 110 7.2.9 References .......................................... 110 8 Day 8 112 8.1 Depth of field ............................................. 112 8.1.1 Circle of confusion criterion for depth of field ........................ 112 8.1.2 Factors affecting depth of field ................................ 113 8.1.3 DOF scales .......................................... 116 8.1.4 Zone focusing ......................................... 117 8.1.5 Hyperfocal distance ...................................... 117 8.1.6 Limited DOF: selective focus ................................. 118 8.1.7 Near:far distribution ..................................... 118 8.1.8 Optimal f-number ....................................... 118 8.1.9 Other applications ....................................... 119 8.1.10 DOF formulae ........................................ 119 8.1.11 Derivation of the DOF formulae ............................... 123 8.1.12 See also ............................................ 133 8.1.13 Notes ............................................. 134 8.1.14 References .......................................... 135 8.1.15 Further reading ........................................ 136 8.1.16 External links ......................................... 136 8.2 Focal length .............................................. 149 8.2.1 Thin lens approximation ................................... 149 iv CONTENTS 8.2.2 General optical systems ................................... 149 8.2.3 In photography ........................................ 150 8.2.4 See also ............................................ 151 8.2.5 References .......................................... 152 9 Day 9 155 9.1 Magnification ............................................. 155 9.1.1 Examples of magnification .................................. 156 9.1.2 Magnification as a number (optical magnification) ...................... 156 9.1.3 Magnification and micron bar ................................. 159 9.1.4 See also ............................................ 160 9.1.5 References .......................................... 160 9.2 Distortion (optics) ........................................... 160 9.2.1 Radial distortion ....................................... 161 9.2.2 Software correction ...................................... 163 9.2.3 Related phenomena ...................................... 165 9.2.4 See also ............................................ 165 9.2.5 References .......................................... 165 9.2.6 External links ......................................... 166 9.3 Optical aberration ........................................... 166 9.3.1 Overview ........................................... 166 9.3.2 Monochromatic aberration .................................. 167 9.3.3 Analytic treatment of aberrations ............................... 173 9.3.4 Practical elimination of aberrations .............................. 175 9.3.5 Chromatic or color aberration ................................. 176 9.3.6 See also ............................................ 180 9.3.7 References .......................................... 180 9.3.8 External links ......................................... 181 9.4 Orb (optics) .............................................. 181 9.4.1 Cause ............................................. 181 9.4.2 See also ............................................ 182 9.4.3 References .......................................... 182 9.4.4 External links ......................................... 182 10 Day 10 183 10.1 f-number ............................................... 183 10.1.1 Notation ........................................... 183 10.1.2 Stops, f-stop conventions, and exposure ........................... 184 10.1.3 Effects on image sharpness .................................. 188 10.1.4 Human eye .......................................... 189 10.1.5
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