Over the past few years, the variety of focus motor systems, all with impressive and sometimes even poetic branding, has burgeoned. So, if you have difficulties differentiating between a Silky-Smooth Voice coil Motor and a Rapid eXtra-silent stepping Drive and you’d like to know how they work, then this article should be of interest to you.
The first three autofocus SLRs, the Pentax ME-F(1981), the Nikon