And here's a brief explanation of how the USM works for those who are a bit vague on the technology (like me ;-):
<http://www.canon.com/technology/canon_tech/explanation/usm.html> Dave On 9/2/06, Cotty <[EMAIL PROTECTED]> wrote: > Paul is right. Make sure you understand what type of motor a USM is. (In > fact Pentax will probably call the system SSM - I'm guessing - as USM is > used by Canon, HSM by Sigma, etc). I have used Canon USM lenses for > several years now and the focus is fast and almost completely silent. > Certainly, outside on a street with the odd car, you will not hear it > all. When I use my wife's *ist Ds, it startles me by comparison. > > Tech-heads will explain much better than me how such lenses work, but > they *can* break. Here's a taster of what one looks like when taken > apart to be inspected: > > <http://www.photoscene.com/sw/tour/inside.htm> -- PDML Pentax-Discuss Mail List [email protected] http://pdml.net/mailman/listinfo/pdml_pdml.net
