“I didn’t read a lot,” Dennis Hopper (1936-2010) once confessed, “but the idea of the decisive moment, catching something at a given moment, was very interesting to me.” Consequently, an unexpected presence presides over “The Lost Album,” an exhibition of Hopper photographs at the Royal Academy, London (through October 19). As you walk around, you keep being reminded of Henri Cartier-Bresson. The great Frenchman was obviously Hopper’s principle influence when he picked up a camera.

Hopper’s best images are at once formally perfect and utterly fleeting. Take his picture of Ed Ruscha — his friend and fellow artist — in 1964, for example. Ruscha, looking almost ridiculously handsome in the James Dean manner, is standing on the street in Los Angeles. Behind him is a window through which a neon sign reads “TV Radio Services.” Mirrored in the glass of the window are the road and the buildings on the other side of the street.