  In the last two decades, Interactive White Boards (IWBs) have been widely
available as a pedagogic tool. The usability of these boards for teaching
disciplines where complex drawings are needed, we consider debatable in
multiple regards. In a previous study, we proposed an alternative to the IWBs
as a blackboard augmented with a minimum of necessary digital elements. The
current study continues our previous research on hybrid design tools, analyzing
the limitations of the developed hybrid system regarding the perceived quality
of the images being repeatedly captured, annotated, and reprojected onto the
board. We validated the hybrid system by evaluating the quality of the
projected and reprojected images over a blackboard, using both objective
measurements and subjective human perception in extensive and realistic case
studies. Based on the results achieved in the current research, we conclude
that the proposed hybrid system provides good quality support for teaching
disciplines that require complex drawings and board interaction.
