So...I'm wondering if all three of these are actually the same lens... http://www.zeiss.com/content/dam/Photography/new/pdf/en/downloadcenter/contax_g/sonnar2-8_90mm_e.pdf http://www.zeiss.com/content/dam/Ph...oadcenter/contax_yashica/sonnar2-8_85mm_e.pdf I've actually been confident for some time that the Zeiss lenses are the same lens in different packaging (I have the Contax G version). The designs are effectively identical. The rear lens element in the Contax G version are recessed enough to make up for the difference in register distance. And the MTF of the two Zeiss versions are effectively identical. Also note that the measured focal length of the two are within 2.4mm of each other. But I only recently did some searching for reviews of the Sony 85mm f/2.8 for my A7 and did some searching for reviews and came across this one: http://kurtmunger.com/sony_85mm_f_2_8_reviewid189.html The moment I saw the box with the optical design on it, I immediately recognized that organization of lens elements. Sony's MTF's are theoretical, not measure, so that's not relevant, but I'm wondering what everyone things about this. Do you think they're all the same lens? That this Sony 85mm is actually the Zeiss design? Thoughts?