When the photographer Philippe Halsman said, “Jump,” no one asked how high. People simply pushed off or leapt up to the extent that physical ability and personal decorum allowed. In that airborne instant Mr. Halsman clicked the shutter. He called his method jumpology....

The idea of having people jump for the camera can seem like a gimmick, but it is telling that jumpology shares a few syllables with psychology. As Halsman, who died in 1979, said, “When you ask a person to jump, his attention is mostly directed toward the act of jumping, and the mask falls, so that the real person appears.”...

One of the purest examples of this joy is an image of Halsman himself, holding hands with a smiling Marilyn Monroe several feet off the ground. Facing his partner, he seems ecstatic, as if he cannot believe his luck. He will hang with one of the world’s most photogenic beauties for eternity. The two are caught in nearly matching, tucked-knees positions. Only a few other subjects, including Murray Kempton and Bridget Bardot, achieved a similar sense of height and compactness. (Ms. Bardot is in a one-piece bathing suit on a rocky bluff, making you wonder how she landed.)...