What have been three technological changes to photography in the last 200 years?

The technological changes to photography in the last 200 years are as follows :-
-First there was only black and white or sepia.
-Then a big revolution was color photography. 
-Then the was the instant photograph so you didn't need a dark room the Polaroid. 
-Finally there was the change over to digital photography. 
-People processed their own black and white photography but not color.

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