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在彩色摄影盛行的今天,国际市场上仍畅销黑白相纸。这是因为用黑白相纸印放彩色底片既简便省时又经济,并且有些人喜欢黑白照片的艺术表现形式。常用的溴素放大纸可用来印放彩色负片吗?回答是:效果不令人满意。因为普通溴素放大纸是感蓝的,对红光不敏感。而一般彩色负片(色罩型)都有一种由黄色和红色构成的“棕红色”马斯克染料色调。这种颜色与通常的“棕色”安全灯的颜色相似。马斯克染料层在彩色摄影中起着防止有害吸收的重要作用,而在黑白放大中却起着“阻光”的作用,导致放大曝光时间过长。由于上述原因,被摄体的红色,在黑白照片上显得十分暗,而蓝色部分则很亮。换句话说,用普通溴素放大纸印放的照片效果就好象透过一蓝色滤光片观察彩色负片一样。为了适应彩色底片的黑白放大,于是出现了一种全色黑白放大纸。目前比较普遍的
The prevalence of color photography today, the international market is still selling black and white photo paper. This is because using black and white photo paper to print color negatives is both simple and economical, and some people like black and white photo art forms. Commonly used bromine magnifying paper can be used to print color negative film? The answer is: the effect is not satisfactory. Because ordinary bromine magnifying paper is blue, not sensitive to red light. The general color negatives (shade type) have a yellowish and red “brown-red” Musk dye shades. This color is similar to the color of the usual “brown” security lights. Musk dye layer plays an important role in preventing harmful absorption in color photography, but plays a role of “block light” in black-and-white enlargement, resulting in enlarged exposure time. Due to the above reasons, the subject’s red color appears very dark in black and white and the blue part is very bright. In other words, the photo effect printed with normal bromine magnified paper is just as if the color negative was observed through a blue filter. In order to adapt to the black and white color negative film, so there is a full-color black and white enlargement paper. Currently more common