The celebrated American photographer and environmentalist Ansel Adams took his first photographs on a Kodak Brownie camera, but it wasn't long before he outgrew it. Within a year he had upgraded his camera, learned basic darkroom techniques and gained enough stamina and skill to photograph at high altitude and under adverse weather conditions. No simple task, but as his work shows, such ascents were to give him a vantage point which turned his landscapes into sublime studies of Mother Nature in all her moods. Few photographers have achieved more.

Examples of Adams's work can now be enjoyed at Modern Art Oxford, where more than 70 of his hand-printed black-and-white photographs are on display. These awe-inspiring images, which express the grandeur of untouched nature, span a period of 50 years - from the 1920s to the 1970s. They reveal Ansel Adams as a visionary figure capable of capturing the sublime in the lens of his camera. His early images were used initially for environmental purposes. Despite believing in both the possibility and the probability of humankind living in harmony and balance with its environment, people were excluded from all those original shots. He wanted the pristine, undisturbed beauty of nature to speak for itself - as it does.

Clearing Storm, taken in Sonoma Country in 1951, captures a carpet of mist which blankets out most of the forest, only revealing the very tips of the trees. A haunting work. Then there's White House Ruin, of 1942, which celebrates the spiritual significance and terrifying majesty of one of the longest continuously inhabited landscapes of North America and home to a community of Navajo people. Aspens, taken in New Mexico in 1958, is a simple study of tree trunks, illuminated partially by falling light, whereas Old Faithful Geyser has harnessed the might of the geyser which he encountered in full flow during 1942 in Yellowstone National Park.

Ansel Adams: Photographs continues until June 1.