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The History of Camera
As early as 1727,a German physicist discovered that light darkens silver salt,a chemical compound.Using as a camera,a big box with a small hole to let the light in,he made temporary images on the salt.Sil-ver salt is still the base of film today.Then a French scientist made the first permanent picture by using a special piece of metal sensitized with silver salt.A photograph he made in 1826 still exists.The painter Dagire improved on the process by placing common salt,the kind we eat,on the metal.This was in 1839,the official date of the beginning of photo-graphy.
But the problem was the printing of the photographs.And it wasn't until other scientists developed the kind of paper we now use that good printings was possible and photography became truly modern.In the 1860's,Matthew Bready was able to take his famous pictures of the American Civil War.
In the 20th century George Eastman of the United States simplified film developing and Dr Edward Land invented the so-called instant camera with self-developing film.If we say that photography came into existence in 1893,it follows that it has taken more than 100 years for the camera to reach its present condition of technical refinement.
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照相机的历史
早在1727年，一位德国物理学家就发现光会使一种化合物——银盐变黑。用一个带小孔的大盒子作照相机，光线通过小孔透入，就能在盐上形成暂时的影像。 今天银盐依然是制作胶卷的基本材料。后来，一位法国科学家用银盐对一块特殊的金属进行感光，制成了第一张永久的照片。他在1826年摄制的一张照片依然保留至今。画家达吉尔将普通食用盐放在金属片上，从而改进了这一工艺。那一年是1839年，也是摄影技术开始有正式记载的年代。
但照片的冲印依然是个问题。直到其他科学家发明了现在所用的相纸，照片的冲印才成为可能。 摄影技术也才真正现代化。19世纪60年代，马修·布雷迪才能够摄制出美国内战的著名照片。
20世纪，美国人乔治·依斯特曼简化了胶卷的冲洗过程。爱德华·兰德博士发明了所谓的一次成像照相机，它带有能够自动冲印的胶卷。如果说1839年摄影术就诞生了的话，那么可以说经过了100多年的时间，照相机才达到现在这种技术上尽善尽美的状态。