one thing you could try is creating a new camera and rendering from that camera instead. (don't forget to change the camera in the render globals to the new camera you created!)

also, ambient lights aren't really good for rendering, you might want to try using another light... but that's an aesthetic thing.

what value is your ambient light set to, and do you have any keyframes on it?

can you give me the primary settings you have in your render settings?