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佳能的EF系列自动调焦镜头是一个庞大的家族,镜头的焦距范围从14mm一直延伸到1200mm。2000年8月,和佳能新型自动调焦单反相机EOS-30一起推向市场的还有几种新型EF镜头,新镜头共有3种规格5个品种:EF28-200mm F3.5-5.6,EF28-90mm F4-5.6,EF28-105mm F3.5-4。5ⅡUSM;前两种规格的镜头,各自都分别有微型超声波马达(USM)和直流马达(DC)两种自动调焦驱动方式的镜头,它们的光学结构则是完全相同的,直流马达驱动镜头的价格要便宜一些;EF28-105mm F3.5-4.5Ⅱ
Canon’s EF series of auto-focus lens is a huge family, the lens focal length range has been extended from 14mm to 1200mm. August 2000, along with Canon’s new autofocus SLR camera SLR EOS-30 to market there are several new EF lens, the new lens total of three sizes 5 varieties: EF28-200mm F3.5-5.6, EF28- 90mm F4-5.6, EF28-105mm F3.5-4.5IIUSM; the first two specifications of the lens, respectively, the micro-motor (USM) and DC motor (DC) two kinds of auto-focus drive lens, they The optical structure is exactly the same, the DC motor drive the price of the lens to be cheaper; EF28-105mm F3.5-4.5 Ⅱ