Abstract: Saw mill for machine vision detection of undesirable features in the wood in shingles being cut from billets and automated optimized saw operation are disclosed. The saw mill includes a transport system that carries the billet through a butt-trimming saw, past a machine vision station, into an transition station for changing direction of travel of the billet and aligning the billet for travel into the subsequent gang rip saw station. The machine vision station determines any defects in the billet, grades the billet according to order-specific parameters, determines the optimal saw cut to maximize the value of the shingle, and sends control data to the gang rip saw controller, to position the saw blades for the optimal saw cut(s) for the shingle. A sorting system receives instructions from the visual imaging system and automatically shunts the product coming from the gang rip saw station into the appropriate container.