减光镜又称中性灰度镜/中性密度镜,简称ND镜,是一块灰色纯透明的高级光学玻璃,其作用就是削弱通过镜头的光亮来降低曝光量。由于这种滤光作用是非选择性的,也就是说减光镜对各种不同波长的光线的减少能力是同等、均匀的,不会对物体原本的颜色产生影响,因此可以真实再现景物原貌。减光镜有多种密度可供 Absorbance, also known as neutral grayscale / neutral density, referred to as ND mirror, is a pure gray transparent high-grade optical glass, its role is to weaken the light through the lens to reduce exposure. Because of this filter is non-selective, which means that the reduction of light of different wavelengths of light dimmer is the same, uniform, will not affect the original color of the object, so you can truly reproduce the original scene. There are a variety of densometers available