A decade or two ago, students learning about, say, Stephen Shore, would head to the library and find a book, or perhaps see some slides projected in a classroom. Now, they sit at a computer and call up some images, which is much worse; because what they’re looking at is only a very rough approximation of what the photographer actually intended. The colors are wrong, the details are missing, the subtleties have vanished. In the absence of those qualities, one tends to focus on content—on what the picture is of or about— effectively rendering all photography a species of photojournalism. The Ansel Adams you see on a computer monitor didn’t make lush, delicately toned nature prints; he took pictures of trees and rocks and stuff.