expensive than acquiring a separate, longer telephoto lens, but as the teleconverter is magnifying the existing image circle, it also magnifies any aberrations. The use of a teleconverter also results in a darker image. Teleside converter A different type of teleconverter called a teleside converter can be mounted on the front of the camera's lens rather than between the primary lens and the camera body. These are popular with users of video cameras and bridge cameras with fixed lenses, as they represent the only way to add more reach to such a camera. They are usually afocal lenses that do not reduce the brightness of the image, but are more likely to add aberrations to the image, independent of the quality of the main lens. Versus extension tubes Teleconverters may be confused with extension tubes, a non-optical component designed to increase magnification (at the expense of reduced focal distance). See also Barlow lens Canon Extender EF Convertible lens Nikon F-mount teleconverter Telecompressor Teleside converter References Photographic lenses