May be it is already known... I just bought a 90mm fat tele-elmarit which is of course uncoded. But my M8.2 knows it is a 90mm lens and the exif even knows it is the "tele-elmarit type II". The code for that lens is 000100 which is just one black bit with the rest all white. Looks like there is a screw head about where the black bit is supposed to be. I guess it is being read as a black bit and the chrome being read as white.