Photography is a hobby for me, though I've gotten a bit more serious in the last few months. I was looking at the Nat Geo photography contest, and it talks about needing model releases for people in the photos submitted. I was wondering how this works out in real life? What if you take a photo of a festival crowd or people in a parade or pretty much any public event? How do people keep track of it all while traveling? Do you need a release for each photo, or can you cover a group of photos? I'm not taking photos with the goal of selling them, but if somebody should want to buy one, I don't want to miss out on funding my photography habit or entering a contest because I don't have a release. Thanks!