A method of aligning a C-arm (26) of an image intensifier for rotation in a selected plane, the C-arm having a transmitter (22) mounted at one end and a receiver (24) mounted at an opposite end, comprising: identifying the selected plane by viewing the location of bony structure (12) with the image intensifier; and aligning indicia disposed on a radio-opaque reticle (25) covering at least a portion of the receiver with the selected plane, the indicia being aligned with the plane of rotation of the C-arm, thereby aligning the plane of the C-arm with the selected plane.