Even on the original NEX 3/5, there were never any problems with DSLR lenses, however wide.
Problems came from rangefinder lenses wider than 35mm.
With the 5N, this is now fixed, as is demonstrated by the fact that the Zeiss ZM 18 works fine with it. But there are still some exceptions, as expertly written up by Dr H. Nasse from Carl Zeiss, when the rangefinder wide angle lens is a symetrical design, like the Zeiss Biogon family, or the CV designs,
Problems came from rangefinder lenses wider than 35mm.
With the 5N, this is now fixed, as is demonstrated by the fact that the Zeiss ZM 18 works fine with it. But there are still some exceptions, as expertly written up by Dr H. Nasse from Carl Zeiss, when the rangefinder wide angle lens is a symetrical design, like the Zeiss Biogon family, or the CV designs,