telephotos

Telephotos are a class of photographic lenses with focal lengths longer than those of standard lenses. In 35mm terms, a telephoto lens is typically considered to have a focal length of around 60mm or longer; the exact threshold varies by camera format. The defining feature is a narrow angle of view and magnification that allows distant subjects to be photographed with more detail.

Most telephotos achieve long focal lengths within a compact overall size by using a telephoto optical design, which combines lens groups to shorten the physical length while maintaining a long effective focal length. Telephotos generally weigh more and are less flexible than shorter lenses. They also produce a shallower depth of field, helping to isolate subjects from the background.

Telephotos come in prime and zoom varieties. Prime telephotos have fixed focal lengths such as 200mm, 300mm, or 400mm, often delivering superior optical quality and brightness. Zoom telephotos cover ranges such as 70-200mm or 100-400mm, offering flexibility for changing distances.

Common uses include wildlife, sports, and portrait photography, where extended reach or subject isolation is important. Handholding such lenses requires care: the long focal length magnifies camera shake, so faster shutter speeds or image stabilization are commonly used. Teleconverters can extend effective focal length but reduce light and may affect autofocus.

In digital photography, practical reach depends on sensor size and cropping; smaller formats adjust the effective field of view differently from full-frame bodies. Telephotos remain essential for distant or detail-rich imaging, balancing magnification with weight, cost, and handling considerations.