FOCAL LENGTH AND PERSPECTIVE

Focal length and perspective — what really changes the image

Focal length changes the angle of view, meaning how much of a scene fits into the frame. Perspective — the relative proportions of elements — is changed primarily by the camera’s position. A telephoto lens does not “compress” space by itself: we usually use it from farther away, and it is this change of position that produces the compression effect.

Wide angle: 10–35 mm

A wide angle shows plenty of the surroundings and strengthens the sense of depth when you move the camera close to the foreground. It works well for landscapes, reportage, interiors and architecture.

• Work close to an interesting foreground.
• Keep an eye on the edges of the frame and the verticals of buildings.
• In portraits, do not move the camera close to the face without a clear reason — changing the distance can strongly exaggerate facial features.

Standard and portrait: 50–85 mm

This range makes it easier to organise the frame and limits the amount of background. For a portrait, choose a distance that renders facial proportions well, then select the focal length needed for your framing.

Telephoto: 135–200 mm and beyond

A telephoto lens narrows the frame and helps isolate the subject. To include the same scene, you usually move farther back — which is why the background appears larger and closer to the subject.

A simple exercise

Place a stationary subject in front of a distant background. Take a wide-angle photograph, move closer, then make a similarly framed photograph with a telephoto lens from farther away. The comparison will show that it is primarily the camera-to-subject distance that changes perspective, while focal length determines the field of view.

Summary

First choose the camera position and its relationship to the subject, then select the focal length for the required framing. This gives you deliberate control over space, the background and the character of the photograph.