Two men lie flat in the snow high in the Himalaya, not moving. One of them has a camera the size of a forearm braced against the drift. They wait. Then the animal steps out onto the rock. A snow leopard, the cat almost nobody ever sees.

He puts his eye to the viewfinder. He watches. He doesn’t press anything. The man beside him flicks his eyes from the cat to the camera, breath fogging in the cold, not understanding. He waits for the click that doesn’t come. “When are you gonna take it?” he whispers, a little disconcerted, as if the chance might evaporate while this guy just looks.

Calm, almost amused, eyes never leaving the leopard, he says, "Sometimes I don't. If I like a moment, for me, personally, I don't like to have the distraction of the camera. I just want to stay in it."

It’s the scene in The Secret Life of Walter Mitty with Sean Penn and Ben Stiller. I saw it and realized how often I fail at this.