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 I want Pentax to bring out a firmware option that will allow us to switch between shaft-drive and SDM AF. Reasons are: 1. Before getting the two DA* lenses, I had not realized how much I rely on audible feedback to know when an AF lens has locked focus. Now I know. In bright light I often can't see the focus indicator in the viewfinder. I would like to have the option of getting that audible feedback. And, no, I won't turn the focus confirmation beep back on. 2. In 10 or 15 years, when Pentax can't repair the SDM mechanism, I would like to be able to switch back to shaft drive. Overall I am not impressed with SDM. Perhaps it is useful for people who really need the quiet focusing. For me it is a big yawn, with some negatives. Pentax engineers hinted that SDM wouldn't focus faster. But even many people who read that interview were in denial about it. Other than this, I like the DA* lenses very much. Joe -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
