Today Ricoh unveils the HD PENTAX DA AF 1.4X AW rear converter. The 1.4X converter not only maintains autofocusing abilities of the camera, but is also weather-sealed like the new K-3 and other Pentax DSLR cameras and lenses. The rear converter measures only 20 millimeters in length. The converter extends the focal length of an attached lens by 40% and the minimum focusing distance of the lens remains the same. It is important to note, however, that when the converter is mounted, the maximum aperture will be smaller by 1 step.
In order to use the converter with your Pentax camera, the camera's firmware must be updated to the latest version before using the autofocus function. Compatible camera bodies are: K-3, K-50, K-500, K-30, K-5 II, K-5 II s, K-5, K-01, K-7, and K-r. Autofocus is possible with a PENTAX lens having maximum aperture of f/4 or brighter.
The converter is composed of four elements in three groups and includes HD coating. This coating is designed to "...minimize reflectance inside the converter while optimizing light transmittance letting the user capture crisp, high-contrast images free of flare and ghosting, even under adverse backlit conditions."
There are 23 lenses that are compatible with the converter.
The HD PENTAX DA AF 1.4X AW rear converter will be available in March 2014 for a price of $599.95.