  The mirror system of the HERA-B RICH consists of two spherical and two planar
mirrors, composed of altogether 116 mirror segments. Analysis of displacements
of the \v{C}erenkov ring center relative to the charged particle track, for
given spherical-planar segment pairs, leads to accurate information regarding
the orientation of individual mirror segments. The method is described and the
effect of applying the required corrections on the \v{C}erenkov angle
resolution of the HERA-B RICH is discussed.
