第一点就是被一些专业人士所熟知的“裁切系数”(crop factor，也称镜头焦距转换率)。

The first is what is known as the 'crop factor'.

youdao

直射光的透过率随着叶面积系数增大而减小，夏半年大于冬半年。

The transmissivity of summer half year is larger than winter half year.

youdao

直射光的透过率随着叶面积系数增大而减小，夏半年大于冬半年。

The transmissivity of summer half year is larger than winter half year.

youdao