What is a “mirror ball?
Mirror balls are spheres with a mirrored surface which reflect the scene around them. They have the interesting optical property of reflecting almost all of a 360° scene apart from a hole directly opposite the camera. Note: “mirror ball” in this context is not the same as a disco ball, which is also sometimes called a mirror ball because it has lots of tiny mirrors stuck to it to reflect light at stimulating angles. Disco balls are of little use to panoramic photographers, except perhaps for recreational purposes.
