What is a Telephoto Lens ?
A telephoto lens is a specific type of a long-focus lens in which the physical length of the lens is shorter than the focal length. This is achieved by incorporating a special lens group known as a telephoto group that extends the light path to create a long-focus lens in a much shorter overall design.
The two most common uses of a telephoto lens by a professional photographer would be:
- Put backgrounds out of focus
- Change the perspective of the picture