Ansel Adams: Eight of the most iconic photos of the American West

Ansel Adams is one of the giants of 20th Century photography, esteemed for his lush gelatine silver photographs of the national parks that have become icons of the US wilderness. A passionate champion of photography as a legitimate form of fine art, he referred to his most stunning images as his "Mona Lisas". But Adams was also a tireless conservationist and wilderness preservationist who understood the power of a strong image to sway public and political opinion.

His stirring images of US national parks have no doubt always inspired a desire to protect the natural world. But his lesser-known images of oil derricks and the decimated landscapes in California's Owens Valley have also taken on a renewed relevance in today's era of climate change.

Ansel Adams in Our Times at the de Young Museum, San Francisco showcases some of his most celebrated works, as well as those that are less familiar, revealing the ways in which his powerful imagery continues to advocate for the protection of the environment.