Focal length


It indicates the focal length of the lens of the respective photo.

  • The focal length is given in millimetres and is the distance between the lens and the focal point.
  • Small focal length:
    • Large image section
    • Objects are reduced in size
    • Large Depth of field (Expansion of the sharp area)
  • Large focal length
    • Small image section
    • Objects are enlarged
    • Small depth of field (extension of the sharp area)

A lens with a short focal length, e.g. 18mm, shows a large image section. This lens is a wide-angle lens, suitable for photographing large subjects, e.g. landscapes, buildings, etc. The millimetre specifications always refer to cameras in 35 mm format with a full-frame sensor (corresponds to the negative size of 35 mm film)

The 50mm lens comes closest to the angle of view of the human eye and is also called a normal lens. 

Telephoto lenses with focal lengths from 70mm are very suitable for animal, sports and portrait photography.

Zoom lenses allow the focal length to be continuously extended or shortened within a certain range, e.g. 70 - 120mm telephoto zoom.

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