Archived posting to the Leica Users Group, 1996/12/10
[Author Prev] [Author Next] [Thread Prev] [Thread Next] [Author Index] [Topic Index] [Home] [Search]In a message dated 96-12-07 23:58:25 EST, you write: << I can't fault Leica for being conservative in the matter of putting out AF reflex lenses. If precision is the name of the game we play, then manual lenses can't be equalled in that class. Bob Rosen >> Bob: I agree with your conclusions. I was intrigued by an article by Herbert Keppler in Pop Photo about six months ago where he reported on a study comparing manual focusing and AF. In all cases, manual focusing won out. He explained that even the most advanced AF system is digital and the system measures contrast and resolves at some pre-determined detent (albiet an electronic one) in the system. Therefore, the most precise system will always be manual, since you can (all other things being equal, such as good eyesight, etc) always hit focus right on the correct spot. The Af system, on the other hand, will drive focus to the nearest focus point which it determines, and which may or may not be the EXACT point of correct focus. It was very interesting. It causes me to come to several conclusions: (1) Manual focus is going to be the best system in all cases except (a) if you have poor eyesight, (b) you are doing fast action [though this is not always going to be the case], (c) you like to have the latest gadgets, (d) you are lazy or (e) some combination of all of the above. I believe that Leitz invented an AF system years ago and still holds the patents on it, but never brought it to market for a number of reasons, chief of which is that it was not precise enough. I do not know the details of this. Some of you Leica-pundits enlighten me, please. Jay Paxton