  The next generation instrument for ground-based gamma-ray astronomy will be
the Cherenkov Telescope Array (CTA), consisting of approximately 100 telescopes
in three sizes, built on two sites with one each in the Northern and Southern
Hemi- spheres. Up to 40 of these will be Medium Size Telescopes (MSTs) which
will dominate sensitivity in the core energy range. Since 2012, a full size
mechanical prototype for the modified 12 m Davies-Cotton design MST has been in
operation in Berlin. This doc- ument describes the techniques which have been
implemented to calibrate and optimise the mechanical and optical performance of
the prototype, and gives the results of over three years of observations and
measurements. Pointing calibration techniques will be discussed, along with the
development of a bending model, and calibration of the CCD cameras used for
pointing measurements. Additionally alignment of mirror segments using the
Bokeh method is shown.
