How to make camera automatically track a path ?

Sounds like you've got everything all set up, but are asking how to animate the camera to go from one null's position to the next?

Video Copilot's SureTarget (it's free) sounds like the simplest solution here, but otherwise is it not just a case of copying the null positions and keyframing the camera?

In terms of automating this, I suppose you could use a CSV file to bring in the next position values but I don't think this would speed things up much.

You can use toWorld to make a single Axis camera look at a 2D null created using the Window/Create Nulls from Paths.jsx panel's Trace Path option, but the created null will be 2D. There is no easy way I know of to use the layer space transformations to generate 3D coordinates for the automatically generated path when you make the layer with the path 3D and move the layer or the camera. Look At is the only option I know of, and I have used that many times to point a camera at something.

Maybe Dan Ebberts can come up with a solution that would let you move the camera or the point of interest based on a Trace Path null, so all you have to do is edit the shape layer path, but it is beyond me.

There is no good way to do it automatically and that's pretty much it. There could potentially be a super convoluted way of doing it with complex expressions referencing the path in a master comp and retrieving the info from there, but that would require to rebuild the project with a suitable structure and is anything but intuitive.

Mylenium