Description of Kenko TELEPLUS Teleconverter Nikon Mount
Increases focal length from same camera position by 2x. Professional quality optics with multi-layer anti-reflection coatings. Compatible with proprietary lenses from Nikon. Precision-engineered in Japan. Tele converter is designed to be used with tele and super tele lenses. It is not recommended to use it with lenses with focal length from 50 mm and shorter. It may affect the quality of the image.
I bought it mainly for moon photography, but it is also good for macro photography. As with any 2x teleconverter, you lose 2 stops of light. Really brings the moon closer with a full frame camera and a 600mm lens. Overall very happy with this purchase. Plan to focus manually with most lenses.