颗粒性(Graininess)当我们将照相底片放大20倍以上时,就会看到原来密度均匀的部分出现了不均匀的颗粒状结构。这就是影象的颗粒性。单个的显影银颗粒很小,人眼并不能观察到,但因它们在乳剂中的分布是无规则的,有些地方比较密集,有些地方比较稀疏,因此看起来就形成了此单个颗粒大得多的斑点状分布图案,这就是颗粒性产生的原因。颗粒性是影象在观察者头脑中产生的不均匀性感觉, Graininess When we enlarged the photographic film by 20 times or more, we saw that the original uniform density had an uneven granular structure. This is the granularity of the image. The individual developing silver particles are small and can not be observed by the human eye, but because they are irregularly distributed in the emulsion, are dense in some places and sparse in some places, it appears that this single particle is much larger The speckled distribution pattern, which is the reason of the granularity. Granularity is the inhomogeneous sensation of the image in the observer’s mind,