Yes, interesting posts by the engineer who started that thread. The conclusion is that ultrasonic motors CAN be faster, it's just that Pentax have chosen a poor implementation (SDM) which doesn't make full use of the technology, and thus it's results are far from optimal (they should have chosen a ring-type motor instead of a micromotor).
A. M. ----- Original Message ---- > From: Joseph Tainter <[EMAIL PROTECTED]> > To: [email protected] > Sent: Saturday, November 24, 2007 8:06:11 PM > Subject: Re: Sigma HSM lenses for Pentax KAF mount > > Bill wrote: > > "OK, I also have a question: what's the advantage of ultrasonic > motors? > > I'm interested in AF speed, since I've had a lot of trouble with my > camera and it's kit lens (annoying AF hunting or even impossible AF in > not-so-low :( light)." > > Interesting discussion here: > > http://forums.dpreview.com/forums/read.asp?forum=1036&message=25727826 ____________________________________________________________________________________ Get easy, one-click access to your favorites. Make Yahoo! your homepage. http://www.yahoo.com/r/hs -- PDML Pentax-Discuss Mail List [email protected] http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
