Please be aware that some of the photographs included in links within this post may contain graphic and emotionally disturbing material.

Which are more powerful, still images or moving ones? Which are more "truthful?" The answer to both questions is, "It depends." A couple of weeks ago, as leaders of G8 countries convened in Italy, a still photograph of Barack Obama supposedly checking out a young woman walking past him and up some stairs, created a stir in the media.

The buzz was that both Obama’s and French leader Nicholas Sarkoszy’s heads were literally spinning when Mayara Tavares, an attractive Brazilian 17-year-old, moved past them. A still photograph showing an unscripted and potentially embarrassing moment spread quickly and all around the world. Were these two world leaders—both married, middle aged fathers—actually caught oggling? And if so, was there something something wrong with that? There was the girl’s father’s point of view. "My daughter is not a model and she is not a sex symbol." Eduardo Tavares told The New York Post. "She is dedicated to healing the poor, not to seducing world leaders. This is the wrong image of my daughter. That photograph has ruined my whole family." Well, maybe, but no one seems to spending much time collecting photographic evidence of that.

But what we did see pretty quickly was an ABC News video of the "incident," shot the same time the still photograph was taken, that told a different story and got the President off the hook. Case closed. Or sort of. I wish I knew what Carla Bruni—a former model and Sarkoszy’s wife—might have thought of it, given that a 1993 nude still photograph of her sold for $91,000, more than 60 times the estimated price, at auction last April.

At first, all the media time, space and attention this photo "story" took up got me thinking about our interest in and appetite for "gotcha" pictures. But it also reminded me of something else altogether—the startling graphic and emotional impact some still photographic images have, in contrast to film or video footage shot of the same event. A classic example of this phenomenon is evident when you compare Eddie Adams’ classic photograph of a Vietnamese general shooting a Vietcong officer and the NBC News footage (no longer available online) taken by a cameraman standing right next to Adams. In the video tape, what transpires happens almost too quickly to grasp. In Adams’ photograph, the violence of the situation and the split second the trigger was pulled, frozen in time, turned iconic. Both the event itself and picture of it made the news and went on to become iconic. As Adams said when I interviewed him about fifteen years ago: "There’s film footage of the shooting, but it’s not what you remember. You remember the picture. This is why I’m a still photographer. You do a still picture, and it’s here today and it’s here tomorrow."