Archived posting to the Leica Users Group, 1999/08/22
[Author Prev] [Author Next] [Thread Prev] [Thread Next] [Author Index] [Topic Index] [Home] [Search]Two issues surround AF focusing. One is the AF detection accuracy and the other is the focusability of the lens itself. The long, fast AF lenses (AF-S Nikkors and Canon-L USM's) focus with deadly accuracy both in AF and manual, and they have almost zero DOF. I've found with my shorter non-AF-S Nikon AF lenses the focus is extremely accurate when using the AF, but more difficult to hit when focusing manually. The super-light touch and short-throw of the lens' focusing rings are impediments to critical focusing for me. The one thing I liked about the Leica R lenses in my brief encounter with them, is that the pitch of the helicoids is more fine-tunable, which makes critical focusing much better. The trade-off is focusing speed, though. I found the Leica R lenses stiffer and needing more ring-turning than I'm used to even with Nikon manual-focus lenses. Inasmuch as I only use a 35mm SLR for wildlife or macro (and carry a couple shorter lenses just in case a photo op pops up) I've stayed with the AF-S and couldn't be happier. For the shorter lenses and 99.9% of my travel and general photography I still haven't found any focusing method swifter or more positive than the M rangefinder.