Teleconverters and extension tubes allow extra, yet affordable reach. Whilst a teleconverter (also tele extender) is a secondary lens mounted between the camera and a photographic lens, an extension tube has no optics. A teleconverter enables more reach for a telephoto lens by multiplying the focal length of the lens, whereas an extension tube is designed to enable a lens to focus closer than its normal set minimum focusing distance. Extension tubes are exceptionally useful for macro photography, enabling you to convert almost any lens into a macro lens at a fraction of the cost while maintaining its original optical quality. Whether Canon or Nikon, make sure that the lens converter or extender is compatible with your primary lens.