Blame the A7r. Sony’s Master plan – new 85, 24-70, 70-200 and more "It’s all down to the A7R 36 megapixel sensor. This sensor, more so than the 24 megapixel full frame, requires a very telecentric lens design. That is, more like a DSLR lens, despite the slim A7 series body. In order to perform acceptably with this sensor, the FE lens range could not be designed to be as small as a rangefinder system equivalent, or to take full advantage of the 18mm mount to sensor distance.Brian Smith, whose images are great (not cheesy portraits) but whose technical info clearly comes via Sony PR, says this: “Mirrorless camera design has allowed Sony’s lens designers to place larger than normal lens element close to the body”. Actually, they don’t, as the design of the extenders will tell you. They’ve used a stronger degree of telephoto construction in the long zoom, allowing a smaller than normal rear element and they have taken measures to move it further away from the body – and this is a general trend. If you want to see what a properly small 85mm f/1.4 looks like try a Carl Zeiss Planar 85mm f/1.4 ZE in Canon mount – 72mm filters not 82mm, 570g versus 850g and really solid all-metal manual focus. The mirrorless bodies do provide a zone from around 16mm to 42mm from the sensor surface which can accommodate the rear of the lens, and can’t ever be used on a DSLR. But Sony does not make full use of that and can not do so because of the microlens, filter layer and structural characteristics of the A7R sensor."