Close focusing distance的意思|示意

It wants to be relaxed for distance, with the ciliary muscle contracting only for brief periods of close focusing.

只有由睫状肌收缩，短暂的近调焦使远距离得到松弛。

While he could mount the lens, if it was not focused at it's closest regular focusing distance, the close up range was inoperative due to some sort of internal body restrictions.

他能装上镜头，如果不能在常规对焦区间的最近端对焦，那么近距对焦就不能工作，原因是机身内部的某种限制。