Techart Contax G to Sony Nex E Mount Auto Focus Full Frame Camera Mount Adaptor &lt;Version 3&gt; Support Auto focusing, fast focusing Allow to focus infinity powerful microprocessor chip Compatible Lens: 21mm f/2.8 Biogon T* / 28mm f/2.8 Biogon T* / 35mm f / 2 Planar T* /45mm F2 Planar T* / 90mm F2.8 Sonnar T* Suggestions how to use: The aperture must be turned to maximum (e.g. F2 in 35mm f/2 lens) and AEL mode to "off" in focusing, then turn the