HOW ARE PHOTOGRAPHS MADE? 



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Which is the positive and which is the negative ? How do the lights and shades 

 in the negative compare with the lights and shades in the positive ? 



Making a Positive. The print is made by allowing 

 white light to pass through the negative to a paper which 

 is sensitive to light. Since less light will pass through the 

 dark parts than through the light parts of the negative, 

 the print will be just the reverse of the negative, or a 

 positive, which has the same value of light and dark as the 

 original objects photographed. Home printing is easy 

 and is a fascinating pastime. Papers are of two types, 

 those printed by artificial light and those printed by sun- 

 light; the former require more time. Blueprint paper 

 is one form of sun-printing paper ; it is cheap and easy 

 to handle since it can be developed in water without the 

 use of chemicals. 



Demonstration 2. Making a Print from a Negative. 



Darken the room until you can barely see objects. Make up a 

 developing bath by dissolving the powders in a tube of developer 

 in water according to directions on the tube. Make a hypo 

 (" fixing ") bath by dissolving a tablespoonful of hypo (hypo- 

 sulphite of soda) in half a pint of water. Arrange three trays or 

 plates as follows : 



