The Met credits Carleton Watkins with a remarkable achievement: he "helped advance the notion" of Yosemite as "a Pacific paradise, a bit of Eden in North America."

Yet even that sells him short. He helped to make it so. Thirty-six photographs and two stereographs, most from the Stanford University libraries, explain why. They show a land still untouched by tourists or developers. They offer a glimpse of Abraham Lincoln, turning aside from the burdens of war to imagine America's future and a more lasting Eden. They also call attention to the role of the still-new medium.

Watkins certainly helped make it so in art. His epic sweep found favor with the Hudson River School, which did so much to provide an image of America as a light among nations in a fallen world. Albert Bierstadt saw Watkins’ work in a New York gallery in 1862, praised him, and purchased a set of his views in 1867. Bierstadt painted perhaps his own grandest view of the American West, now in the Brooklyn Museum, in 1866, the year of the photographer's third trip to Yosemite. While was painting the Rockies, Bierstadt himself had been inspired to visit Yosemite and to experiment with albumen silver prints and stereographs. His Looking Up the Yosemite Valley in oil followed the next year.

One can see many of the same hallmarks in both men. They provide an ample foreground as an entry into the picture. It may have the mirrored surface of a lake or river. Trees, dwarfed by the scene as a whole, set the scale. They have the particularity of portraits, perhaps as stand-ins for the photographer himself. They lead the eye beyond to a cavernous space filled with light—and, at a greater distance, craggy heights.

Yet Watkins helped make it so in life as well. The New Yorker may have moved to California as early as 1849, at age twenty, settling in San Francisco—where he lost his studio to the 1906 earthquake, a decade before his death. He paid his first visit to Yosemite in 1861. As curator Jeff L. Rosenheim notes, the photos "established his reputation." They also came to the attention of President Lincoln. A paradise must be preserved, and Lincoln signed a bill in 1864 seeing to its preservation as the first step toward what would become a system of national parks. When Watkins returned in 1865 and 1866, he was working on behalf of the California State Geological Survey.

That task points to his distinction from the Hudson River School, too. For painters like Bierstadt and Frederic Edwin Church, the land partook of the Romantic sublime, larger than life, but clear in its path for humanity into nature. Watkins sees a wilderness that defies access, with large rocks in the middle distance, treacherous waters, or the sheer face of distant cliffs. And he takes as his subject a single landmark, such as Mirror Lake, the Half Dome, El Capitan, Cathedral Rocks, the Bridal Veil, a tree as old as human history, or a waterfall shrouded in mist—under clear skies without once an approaching storm. Only twice does he ascend to create a panorama, and only once does he look to compose "the best general view." Like a geological survey, he has to map out feature-by-feature what is there.

That ascent makes a heady reminder of the technical challenges. Watkins was carrying literally a ton of equipment, including glass plates and dangerous chemicals, in order to achieve what were then huge prints (18 by 22 inches) of painstaking clarity and pristine whites. On his first trip he had to tilt the lens to capture the scale in front of him, and on his return he had to lug an even clumsier camera more capable of dioramas. He needed it to advance the notion of Yosemite. In the past, the Met has argued for painting as a response to a divided America and for Civil War photography as an unprecedented record of death and destruction. Thousands of miles from the front, Watkins was looking ahead to the recovery of a larger nation.