70-200

The distance between the centre of the lens and the film, the focal length, ensures the object is accurately focused even when the subject is located quite far away. It is measured in millimetres and is marked on the camera mount along with the largest aperture for the photographer’s convenience. A focal length of any given camera decides its category into normal, telephoto and wide angle. It is essential in photography as it establishes field of view of the camera, which is indirectly proportionate to the focal length. A normal lens that is compatible with 35 mm film with the focal length of 50 mm, gives a field of view that is almost equivalent to that of a normal vision of humans. A telephoto lens is available in a wide range of focal lengths: 60 mm to 1000 mm. 70-200 mm is a term used for telephoto zoom lens made for SLR cameras.

Though the specification of this lens may differ from manufacturers, it is usually available in two maximum aperture size: f/2.8 and f/4, albeit four image stabiliser stops. This lens enables the photographer to capture high quality images. It is extremely useful for shooting portraits as with f/2.8 the background remains out-of-focus, bringing the subject more prominently in the picture. Depending on the AF speed offered by the manufacturers, this lens can prove to be a boon for street photography. Canon EF 70-200 mm is one of the most popular lenses in this category along with Nikon, Sigma and others. These lenses are lightweight and easy to handle.