Archived posting to the Leica Users Group, 1999/03/30
[Author Prev] [Author Next] [Thread Prev] [Thread Next] [Author Index] [Topic Index] [Home] [Search]The biggest difference between *most* AF lenses and their MF counterparts, in the Nikon line, for example, is that the focusing mechanism is much less damped and has a much shoter throw from infinity to close focus. The total travel on my 35mm f/2 for example, is around a 90 degree turn. These compromises are made so that the small motor in the camera body can focus the lens at a reasonable speed. But, this doesn't have to be the case. If you put the right kind of motor *in the lens*, like Canon has been doing for a decade, then you can build lenses that have a longer, better damped focus action and that still autofocus very quickly. Personally, I tend to use manual focus, even with my autofocus body, and I use the AF sensor and focus confirmation as a rangefinder device for wide lenses. This works really well on even on older (F4, N8008s) Nikon bodies. It would be nice to see Contax (aside from the RX and AX) or Leica put something like this in to their newer cameras. The electronic rangefinder is nice because you can get the effect of a split-image rangefinder focus screen without having to actually use one. Those screens are annoying for macro work, because the whole center of picture blacks out when you stop down to check DOF, for example. Cheers, Pete