That's a solid improvement, but I bet they could get better results with some other machine vision tricks. Diffuse on-axis lighting [1] would probably be a good

That's a solid improvement, but I bet they could get better results with some other machine vision tricks. Diffuse on-axis lighting [1] would probably be a good approach for this application; it's good at making subtle markings on flat surfaces stand out. [1] http://www.microscan.com/en-us/products/NERLITE-Machine-Vision-Lighting/Smart-Series-DOAL-Illuminators.aspx http://www.microscan.com/en-us/products/NERLITE-Machine-Visi...