光滑平面上汗液指印的拍摄

Potential Sweat Liquid Finger Mark is Shot on the Smooth Plane

犯罪嫌疑人遗留在各种光滑平面上的新鲜或陈旧性汗液指印，由于潜在指印与背景之间的反射亮度差很小，加之背景颜色的干扰，一般光照条件下拍摄相当困难。运用定向反射照相法，能加强纹线与背景的亮度差异，消除背景颜色的干扰，妈得较好的拍摄效果。

It is difficult to photograph the fresh or outmoded sweat liquid finger mark on various kinds of smooth planes made by suspects because of small difference of reflecting luminance between potential fingerprints and the background,the interfer-ence of the background color,as well.Taking pictures by means of oriented reflecting method will strengthen the difference be-tween the lines and luminance of the background,dispel the interference of the background colors and make better result of shooting.