telephoto lens

optics

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Last updated

July 14, 2026

Quick Summary

A telephoto lens is a type of camera lens designed to make distant objects appear closer. While often used interchangeably with "long-focus lenses," telephoto lenses are specifically designed to be more compact than their focal length would suggest. This is achieved through a combination of lens groups that shorten the overall length of the lens and the distance from the rear element to the film.12

Accessory teleconverter lenses can also be used with a prime lens to create a more compact telephoto system, though this may reduce the lens's speed and sharpness. Lenses are key components in optical systems, controlling the passage of light and influencing image quality.23

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technology of photography
Telephoto lenses
Long-focus lenses are bulky, because they comprise not only the lens itself but also a mount or tube to hold it at the appropriate focal distance from the film. Telephoto lenses are more compact; their combinations of lens groups make the back focus…
Read More
Long-focus lenses are bulky, because they comprise not only the lens itself but also a mount or tube to hold it at the appropriate focal distance from the film. Telephoto lenses are more compact; their combinations of lens groups make the back focus…
Read More