try this...
create new blank chor
select the camera view
Turn out of it and Zoom out until the camera can be seen. The center of the Turn should be the 0,0,0 point of the ground
Click on the camera to select it, then press T for Turn.
Watch the numbers for horizontal and vertical on the bottom change when you click in the back ground.
Select the ground again, the press T again. The numbers will revert to what they were before when you click on the background again.