Kenko 1.4X Teleplus PRO 300 DG AF

(From company literature) Kenko Teleplus Pro 300 DG converters are made with precision quality multicoated optical glass supplied by Hoya Corporation, the world's largest manufacturer of optical glass. These glass elements were designed to match the optical quality of the prime lens (even at the edges) and telephoto zoom lenses. The optical design of the elements and light path is wide enough not to cause vignetting. The DG version is optimized for use with digital SLR cameras, as well as film cameras.

The PRO 300 DG family are designed specifically to be used with prime telephoto lenses of 100mm or above, such as the Tokina AT-X 300 AF PRO, 300 mm f/2.8 lens, and work best with telephoto lenses of 200mm to 500mm. The PRO 300 can be used with telephoto zoom lenses as well as prime lenses. However, Kenko does not recommend them for zoom lenses that have a range starting under 50 mm.

Kenko PRO 300 DG AF Teleplus converters have genuine Gate Array IC (Integrated Circuit). This means that the converter's own unique circuitry maintains signal integrity between the camera body and lens. These converters are designed to electronically operate the same way as an original manufacturer's converter.

With the PRO 300 1.4x, full AF operation is possible with camera lenses having a maximum aperture of f/4 or brighter. The same light and contrast requirements apply.