photo:fov

see also:

- angular field of view is the viewable scene through your system measured as an angle
- human cone of visual attention is ~55deg which equates to a 43mm focal length lens on a 35mm full frame camera hence lenses with focal lengths in that vicinity are regarded as “standard lenses”

- angle of view in radians = 2 x arctan (d/2f) where d = size of dimension of sensor in mm and f = effective actual focal length in mm
- for telephoto lenses, this approximates to
**angle of view in degrees = (180/pi) * (d/f)** - effective focal length:
- for most photography, this is the actual focal length as stated for the lens
- for macrophotography, the effective focal length = actual focal length x (1+magnification factor), such that for a 1:2 macro, the magnification factor is 1.5
- for telescopes, effective focal length depends upon whether other elements are used and how they are used such as eyepieces and Barlow lenses

- as an example of subject size, apparent angle of the moon and sun is approx. 0.5 deg

- sensor is 36mm x 24mm and a diagonal of 43.3mm

effective focal length | horizontal fov | vertical fov | diagonal fov |
---|---|---|---|

50mm | 39.6 | 27.0 | 46.8 |

100mm | 19.8 | 13.5 | 23.4 |

200mm | 9.9 | 6.75 | 11.7 |

300mm | 6.6 | 4.5 | 7.8 |

400mm | 4.95 | 3.38 | 5.85 |

500mm | 3.96 | 2.7 | 4.48 |

1000mm | 1.98 | 1.35 | 2.34 |

2000mm | 1 | 0.68 | 1.17 |

5000mm | 0.4 | 0.27 | 0.45 |

- sensor size is 17.3 x 13.0mm and a diagonal of 21.63mm = half the diagonal size of a 35mm sensor hence the 2x “crop factor”

effective focal length | equivalent focal length in 35mm system | horizontal fov | vertical fov | diagonal fov |
---|---|---|---|---|

45mm | 90mm | 22 | 16.5 | 27.5 |

50mm | 100mm | 19.8 | 14.88 | 24.78 |

75mm | 150mm | 14.85 | 11.16 | 18.59 |

100mm | 200mm | 9.9 | 7.44 | 12.39 |

135mm | 270mm | 7.3 | 5.5 | 9.2 |

photo/fov.txt · Last modified: 2013/02/17 08:54 by gary1