Troposcatter film apart from dirty were the exposure into the second time, the first time is the primary exposure, no need to troposcatter film, the exposure time is about normal exposure time of 4/5;

• 散射膜不兴不净操纵办法是：不兵曝平不合成二次举动，第一次是宾曝平，务必散射膜，曝平工夫约为变态曝平工夫的 4／5；