optimum aperture

基本解释

Aperture used and consequent depth of field as well as use of optimum aperture.
所用的光圈以及其相应景深；是否使用了最佳光圈；
Optimum position of sprinkling aperture and formula of rotating speed are derived.
推导出了最佳开孔位置和转速的计算式。
Of course using such film means ISO speeds of under 100, which means that a tripod, cable release and mirror lock-up are a necessity when combined with the use of the lens' optimum aperture.
当使用最佳光圈时，你还应该同时使用ISO100或者更低速的胶卷（如ISO50的FUJI VELVIA - 译者注），相机的反光板锁定功能，三角架，以及快门线。