Re: Mysterious pins on R8 lensmount

[Donal Philby <donalphilby@earthlink.net>]

George Huczek wrote:
> 
> Is Leica planning to come out with autofocus lenses in the near
> future? Those mysterious pins inside the R8 lensmount would suggest
> that their R&D department might have something planned in the
> near future.
 
> would like to know why or how an autofocus lens per se creates
> problems in optical quality. If such a claim about reduced optical
> performance in AF lenses can be supported, then wouldn't it be
> a mistake for Leica to go in this direction?

One key element in fast autofocus is lightweight materials--whether 
glass (plastic), metal or composite.  Canons focus fast, for one 
reason, because there is so little mass to move.  But this also makes 
them fragile.  One of my studio partners had a 400 f/2.8 that was in 
the shop 8 times in a year and a half.  He just bought an F5 and 
replaced the Canon with a new Nikkor 400 2.8.  It seems a bit heavier, 
but focus speed and quality of optics are a quantum leap.  How you 
would do the kind of team sports pix he does with the vastly more 
expensive but manual focus new Leitz telephotos, I can't imagine.  I 
would love to know who will be buying the new modular systems for the 
R.

Currently, the pins can tell focal length and transmit that info to a 
zoom head strobe.  The new lenses will come with pins and chip built 
in.  Old lenses, according to Leica USA can be retrofitted with pins 
and chip for $100.  Apparently Leica decided that the goodwill of 
inexpensive retrofitting was worth the investment.  I applaud that 
decision.

And of course there are the rumors of passive focus confirmation.  I 
have such in my Nikon N90s, but don't think I have ever used it.  
Autofocus or bust.

According to Mike Blanchot, So Cal Leica rep, Leitz experimented with 
focus plane autofocus a la Contax AX over ten years ago, but decided 
it wasn't good enough, especially because without the internal focus 
element moving, there were optical degredations they considered 
unacceptable.

- --Donal Philby
  San Diego