Perspective and portrait lenses

For further photography-related information check out my compendium of tips.

The relative dimensions of an object alter as you change your spatial relationship to it - this effect is known as perspective (and is fundamental to an appreciation of composition). This was amusingly illustrated in an episode of Father Ted when he tried to explain the concept to the dim-witted Father Dougal. The small toy cow he held just in front of Fr Dougal only appeared to be the same size as a real cow in the distance due to perspective - alas the idea was too subtle for him to grasp!

The photograph above was shot with an ultra-wide angle lens at a focal length of 16mm. Not a pleasant sight! To fill the frame with such a lens requires you to get very, very close to your subject (about 5cm in this case). This means that the nose looks much bigger than we're used to seeing - thanks to the unusual perspective.

The above shot was taken with a medium telephoto lens at a focal length of 80mm and is much more pleasant to look at. To fill the frame with the longer (and hence more magnifying) focal length requires the subject to be a much greater distance from the camera (in this case about 2m), giving a more flattering perspective to the face.

This is why lenses in the focal length range of 70-130mm are referred to as 'portrait lenses'. They force the photographer to stand a sufficient distance from the subject in order to fill the frame which gives a pleasing perspective to the subject's face.

Please check out my portrait photography here: Kent portrait photographer