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单反光圈什么意思

更新时间: 2020-10-31 00:00:00     

光圈通俗点讲,就是镜头中间有一个可以控制通光量的小孔,如果将这个孔开大,曝光时间一定就越大,将会有更多的光到达底片(感光器)上,相反,如果将孔开小,那么会减少到达底片上光的量。

光圈的值(f值),数值上等于镜头焦距与光圈直径之比值。所以,在镜头焦距相同的情况下,光圈值越大,光圈越小。

关键词: 光圈 什么 意思

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