Complete aside - Comment about posted pictures from Digital Eye Glass I noticed from his posted pictures (labelled as Possible Witness 2) http://2.bp.blogspot.

Complete aside - Comment about posted pictures from Digital Eye Glass I noticed from his posted pictures (labelled as Possible Witness 2) http://2.bp.blogspot.com/-RnoG7dHRDjY/UASnGzPFkSI/AAAAAAAAADA/8zPAI5x2Cm0/s640/cashier.jpg http://2.bp.blogspot.com/-RnoG7dHRDjY/UASnGzPFkSI/AAAAAAAAAD... There's some nasty spherical lensing effects there. I'm noticing that from the signboard on the right middle side. The menuboard should be flat across, with perhaps a deviation of where the signage isnt exactly flush to each other. Also in other pictures, you can see spherical lensing distortion from the corners of walls and ceiling tiles. I know of libraries that take low compute overhead that compensate for this. And all you need for calibration is a checkerboard of white and black waved around.