尘埃对感光材料的污染大致可分为三种情况: 1.尘埃对感光材料不起化学或机械作用,曝光时,尘埃投影范围内的感光乳剂不感光,其影响范围同尘埃的投影面积。2.尘埃对感光材料主要起化学作用,其影响范围比尘埃尺寸大得多。3.尘埃对感光材料主要起机械擦伤作用,造成感光乳剂的涂布不匀。这也是尘埃 Dust on the photosensitive material pollution can be broadly divided into three situations: 1. Dust on the photosensitive material can not afford chemical or mechanical effects, exposure, dust projection within the scope of the emulsion is not sensitive to light, the impact of the same area with the dust projection. 2. Dust on the photosensitive material mainly from the chemical reaction, the scope of its influence is much larger than the size of dust. 3. Dust on the photosensitive material mainly from the role of mechanical abrasion, resulting in uneven emulsion coating. This is also dust