Well, we may not say it. The woman might say it, though.

Just had a thought (a rare event, I know).
So let's say you're gawking at a busty/hot woman and you have your camera handy, but not in view. Irritated, she says to you, "Take a picture, it lasts longer." Reply with, "Okay, but you'll have to do something funny," with a pleasant smile on your face. As she puzzles over this comment, whip out your camera and take her picture.

Alternatively, you could tell her to do something funny, stick out her tongue, stand on one foot, ham it up, meow, etc. Maybe hand her a prop (something pointless, but a prop nonetheless) to hold.
Funny + cocky can go a long way.

I think my new mantra is gonna be "Take a picture, it lasts longer."
