Flipping camera

So, there is a camera that follows a curve and an empty that follows other curve that is almost the same as the cameras curve. The camera is tracked to the empty. At on point the empty starts going up and goes over the camera. Now the camera flips over in one frame. How could I get it not to flip?

I also wonder if there is any tutorial that tells how to get a good video out of blender. What codecs should I use, how to get them on blender and so on.

Oh, almost forgot: How to speed up or slow down the animation?

Well, I don’t know about the other stuff, but if the empty goes directly over the camera, it’s going to flip. Move the path of the empty so it doesn’t pass directly over the camera.

This is not an option in this case…

You can’t adjust the path even slightly?

Unfortunately no.
There is a “?” mark and the camera and empty starts from the right side of it going down, then goes from the hole and then up following the shape to the point where it is almost at the top (still beneath the hook). Now the camera and empty starts going each one to the other way that one can see the “?” mark.
Unfortunately for me the camera flips at the point it starts going up.

So, there isn’t any way to prevent this from happening, right?