A magnetic mounting assembly for securely attaching a positionable object to be variably fixed in a desired selected position to a support, for universally moving the positionable object to the desired selected position, and for holding the positionable object in that position during operation is provided, including a positioning element with a ball that is attached to the positionable object. A support element includes a socket configured to movably engage the ball. One of either the ball or socket includes a magnetic material and the other includes a magnetically attractive material to hold the ball in the socket by magnetic as well as frictional forces. An adjustment collar controls the axial movement of the ball to increase or decrease the magnetic force holding the ball in the socket. This mounting assembly is particularly useful for supporting a camera on a tripod.