They're no different than any other agency in that they'll do everything they can to screw the photographer. The only real difference is that they are bigger. On one hand, if you get something out of it that you wouldn't have otherwise, I guess that's good. On the other, unless you're committed to being a stock rock star, you'll probably just get lost in the noise.
As for Flickr, they basically troll for salable images to add to their inventory, selling them to people that could just have easily found them on their own; the only difference is, Getty gets the money for acting as the broker, where the photographer could have gotten everything. It all depends on how you value yourself and how much effort you want to make; sometimes it's just easier to make less and leave the heavy lifting (if you could call it that) up to someone else.
Good luck :D |