Whenever I switch to 3rd Person, problems occur. As I said, the camera goes beyond terrain when pushed against it, and whenever I look down on a slope, it just gives a close-up view. Like in 1st Person. Please help!
You'd need to share a lot more details about your camera controller with us. Maybe even a minimal project we can all look at. As it stands all I can tell it sounds like your camera controller likely features no collider or logic to keep it out of walls and whatnot.
Not certain about your specific problem, but I was going to try and use a ray cast from the camera look point back to camera, to keep the camera out of walls and terrain.