Patrick Warnshuis <[EMAIL PROTECTED]> wrote:
>Is plastic really such an anethema to image results?
>I suspect one engineering design consideration with respect
>to the newer AF lenses is that they MUST be lighter to
>reduce inertia and resistance for faster, more accurate
>positioning, both features demanded by users. Yet these
>same users resist the resultant 'feel' of the newer lenses.
>And, obviously, in order to meet the demands of faster and
>more accurate AF, the throw of the focus ring and its feel
>will not compare with the needs for MF so that the AF lens
>operated in the MF mode will not replicate the feel of a MF
>dedicated lens.
The 'feel' of AF lenses isn't only due to the use of plastic. Much
of it is due to having to make the lens focus quickly. Note that
many AF lenses have a very short throw from min. focus
to infinity. Because of this short throw, it isn't as easy as manual focus
lenses to make
fine adjustments in focus since the focal plane moves very quickly
with a relatively small movement of the focus ring. (That is what
makes Minolta xi lenses so horrible with its motorized focus.)
An exception, IMO, is the Nikkor 20mm/f2.8 AFD. That has a manual
focus feel to it. It manually focuses smoothly and is easy to make fine
adjustments.
David Johnson
