Kenko's TelePlus PRO 300 DGX 1.4x AF Teleconverter (also known as a tele-extender) doubles the focal length of your lens while retaining the prime minimum focusing distance. Depth of field is decreased by 1/1.4. The 4-group design features multi-coated lens with seven elements. It has a fully automatic diaphragm coupling. Using a 1.4x teleconverter with (for example) a 300mm lens gives an effective focal length of 420mm.
The TelePlus series of converters has Gated Array Integrated Circuitry. This permits the signal between prime lens and camera body to continue unimpeded, meaning that autofocus will function correctly where lenses have an aperture of f/4 or brighter. Lenses with lower f/stop values it may be necessary to focus manually. The circuitry transmits data not only fro mthe converter but also from the camera body and also provides more accurate recording of meta-data.
- For Use with Digital SLRs
- Lens Elements are Multi-Coated
- Proprietary Gated Array Integrated Circuitry
- Focal Length of Lens is Doubled
Please note: This Kenko teleconverter is incompatible with Canon EOS EF-S lenses.
IMPORTANT: Teleconverters are not recommended for lenses larger than 50mm (for example 28-105mm, 75mm etc). Full AF operation can only be realized with lenses of open aperture f/2.8 or brighter. Autofocus will only work correctly if there is sufficient light and contrast on the subject to trigger the camera's AF sensors. For smaller f-stop values, manual focusing is recommended.
Updated by Mark S 07/16/2014