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一段时期以来,日本各相机公司已将28～105mm镜头作为其标准变焦镜头的主流产品,有的更已扩展到24～105mm,以及更大变焦比的镜头。这类镜头光学性能、操作性及牢固性程度究竟怎么样?笔者近日试用了两款比较常见的标准变焦镜头-美能达Xi f28～105/3.5～4.5和佳能EF f28～105/3.5～4.5镜头。美能达Xi f28～105/3.5～4.5镜头作为90年代初期推出的美能达xi系列AF相机的主力配套镜头,曾经风光一时,其电动变焦功能也曾带给人们以新奇感;但随着时间的推移,人们感到所谓电动变焦并无多大实用价值,故此,美能达公司自已早已放弃了在其AF相机及镜头上配备这一功能。但实实在在地讲,该镜头仍有很高的使用价值。该镜头的基本规格如下:外形尺寸ф73mm×76.5mm;光学结构10组13片;光圈范围F3.5（4.5）～F22（27）;最近对焦距离0.5m;最大倍率1:4;滤镜尺寸62mm;重量450g。
For some time now, Japanese camera companies have adopted 28- to 105-mm lenses as the mainstream products for their standard zoom lenses, and some have even expanded to 24-105mm lenses with larger zoom ratios. This kind of lens optical performance, operability and firmness how exactly? I recently tried two of the more common standard zoom lens - Minolta Xi f28 ~ 105 / 3.5 ~ 4.5 and Canon EF f28 ~ 105 / 3.5 ~ 4.5 lens . Minolta Xi f28 ~ 105 / 3.5 ~ 4.5 Lens As the early 1990s launched Minolta xi Series AF camera supporting the main lens, once the scenery, the power zoom function has brought people a sense of novelty; but over time Passing, people feel the so-called electric zoom and not much practical value, therefore, Minolta company has long been abandoned in its AF camera and lens equipped with this feature. But to be honest, the lens is still very high value. The basic specifications of the lens are as follows: Dimensions ф73mm × 76.5mm; Optical structure 10 groups of 13; aperture range F3.5 (4.5) ~ F22 (27); the closest focusing distance 0.5m; maximum magnification 1: 4; 62mm; weight 450g.