an optical accessory increases the local length of lens it's attached to
a piece of equipment that sits between your camera and the lens
a small lightweight intermediate optic that will increase the magnification of a lens, while reducing its effective aperture
a special lens placed in between camera and camera lens
An optical system used to increase the effective focal length of the lens that is mounted between a camera body and the lens.
A device, used to increase the effective focal length of a lens that consists of optical glass. It is mounted between the camera and the lens and usually comes in two different sizes: 1.4X and 2.0X. A 1.4X teleconverter increases focal length by 1.4 times, while a 2.0X increases focal length by 2.0 times. The aperture of the lens is also increased by the same amount as the focal length is increased. For example, a 2.0X teleconverter increases focal length of a 200mm lens to 400mm; however, the aperture of F/2.8 is decreased to F/5.6.
Also known as extenders, attach between the camera body and the lens to increase the focal length.
A teleconverter is a group of lenses which is mounted between the camera and a photographic lens. Its job is to enlarge the central part of an image obtained by the objective lens. For example a 2× teleconverter enlarges the central 12×18 mm part of an image to the size of 24×36 mm.