HOW ARE PHOTOGRAPHS MADE? 



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forerunner of the great photographic industries of today. 

 Think of the persistence of a man working on the idea that 

 sunlight with the aid of a few chemicals could make a per- 

 manent picture. It took Daguerre fourteen years to work 

 out his idea. Some 

 others had devised 

 processes by which a 

 picture could be made 

 if exposed for hours 

 in a dazzling bright 

 light. But that was 

 not practical for 

 photographing people . 

 In 1839, Daguerre had 

 perfected his process 

 so that an exposure of 

 a few minutes was 

 sufficient to take the 

 picture. These were 

 made on a metal base 

 and no duplicates 

 could be printed from 

 it. Today a fraction 

 of a second only is 



In the first portraits made with a camera the 

 face had to be covered with white powder to 

 reflect as much light as possible. The sub- 

 ject was then exposed to direct sunlight before 

 the open camera for 30 minutes. 



needed to expose a plate or film and from the negatives 

 any number of pictures can be printed. Such are the 

 strides made by science in a few years. Today photog- 

 raphy has become a leisure time activity for all, and 

 the pages that follow will help you to enjoy this scientific 

 pastime. 



The Camera. We think of a camera as a light-tight 

 box having a lens at one end and a place at the opposite 

 end for a prepared photographic plate or film. But there 

 is a simpler camera than that because pictures can be 

 taken without a lens. In such a camera there is only a 



