Web medium orientation detection

Printing system for printing web media, comprising:

• a take-out roller;
• a take-up roller for pulling a web medium along a media transport path from the take-out roller to the take-up roller;
• an image forming unit positioned along the media transport path,
• characterized by:
• an orientation sensor for sensing an orientation of the web medium, the orientation sensor comprising:
• a curved medium support surface defining a turn in the media transport path, which curved medium support surface is tiltable around a tilting axis, which tilting axis extends in a transport direction substantially tangentially to the curved medium support surface in a reference orientation;
• a tilting sensor for determining tilting data proportional to a tilting angle by which the curved medium support surface is tilted from its reference orientation around the tilting axis;
• a controller configured to:
• receive the tilting data from the orientation sensor;
• compare the tilting data to the reference orientation to determine an orientation error;
• and
• compare the orientation error to a deviation threshold.