A capacitive sensing system based on projected self-capacitance is suitable for use in printing systems/products to sense paper tray status. In example embodiments, a capacitive sensing system is adapted for sensing the condition/characteristics of paper in the paper tray, such as paper size, stack height and page count and paper dielectric. The capacitive sensing system can be configured with one or more shielded capacitive sensors incorporated into the paper tray, and oriented relative to the paper according to the paper condition/characteristic sensed.