April 04, 2008
This is part of an ongoing series of short articles about lenses and how they are used on Digital SLR cameras. The series currently contains the following articles:
These lenses have focal lengths that are longer than normal. Wildlife and sports photographers favor the longer versions of these lenses (200mm and up) as they allow you to get in close to the subject while still shooting from a distance.
Many portrait photographers like the shorter telephoto lenses such as 85mm or 135mm. These focal lengths make it easier to create a shallow depth of field, blurring the background and isolating the subject.
Perspective distortion is a function of how close to the camera the subject is. In a telephoto lens the perspective is compressed—objects in the view of the camera appear to be very close to each other. In the image below the giraffe and many of the trees appear to be about the same distance from the camera, even though they are several yards (meters) apart. The image was taken at 200mm.
The apparent compression of distance these lenses create also help to minimize things like large noses—another reason they are often used by portrait photographers. And you can seed from the above image how wildlife photographers can use them to get close to their subjects from a safe distance.