請問攝影的halftone process是什麼呢!

對ㄌ
請這下面這一句要怎樣翻比較好
The discovery of halftone process in photography in 1881 made it possible to reproduce photographs in books and newspapers.

halftone process
是半色調效果.....
就是只用黑跟白表現圖片，photoshop裡也有這個功能
跟灰色調不同的是反差更大，不會有中間色的模糊感。


The discovery of halftone process in photography in 1881 made it possible to reproduce photographs in books and newspape.
大概的意思是說︰

於1881年發現的半色調攝影可應用於書本及報紙印刷。

非常謝謝!