Camera's are an interesting phenomenon. We only turn them on for moments we want to capture. Moments of joy and things that we want to remember.
When you get the news that someone is dying, you don't whip out your video camera and start shooting, you wouldn't even think about it. But if you hear that someone is pregnant, the video camera is one of the first things you think about. Both moments are equally momentous in people's live, a beginning and an end, but we only record the one that will give us happy memories, happier stories to tell to others when they see the record of that event.
We try and create our own documented myths about ourselves, about our lives. That all we've had has been good moments, that we lived our lives well. Think about that damn nickleback song, the opening line: "look at this photograph, every time I do it makes me laugh..." The song wouldn't be nearly as catching if he was singing about bad times.
Photographs are an attempt to keep memories closer to us, but it also seperates us from them. Someone taking pictures is always seperated from what he's filming. If you're taking pics of a soccer game you're not out there kicking the ball and having fun. You're steadying the shot and trying to focus.
Sorry, I had that nickelback song stuck in my head and a bit too much free time at work to think....