Modern era

 Annie Leibovitz photo of John Lennon and Yoko Ono is one of the most widely reproduced of the era.

Antonio Zambardino — Italian photographer who covered social and environmental issues
 Sebastiao Salgado — Brazilian photographer who is considered a modern-day Lewis Hine.


Also see:  
Atlantic Magazine: America in the 1970s 
 America in the 1970s: National Archives