A telescopic endoscope employing a primary endoscope (30, 50) having a instrument channel, a miniature secondary endoscope (40, 60) deployed within the instrument channel of the primary endoscope (30, 50), and an endoscope tracker including one or more sensors (32, 61) and one or markers (41, 52) for sensing any portion of the miniature secondary endoscope (40, 60) extending from a distal end of the instrument channel of the primary endoscope (30, 50).