Abstract: Apparatus for inspecting transparent containers having sidewall portions of differing optical properties that includes a pair of discrete light sources for directing light energy through the adjacent essentially discrete portions of the containers having the differing optical properties. A camera receives light energy directed through the container from both of the light sources as a single image of the entire portion of the container illuminated by both light sources. Commercial variations are detected as a function of variations in light intensity at the camera. The camera includes an array sensor that receives light energy transmitted through both of the container portions, and is scanned at increments of container rotation so as to develop an electronic image of the entire portion of the container illuminated by the light sources.