A detection segment for use in a device for printing on containers includes an image-capturing device that optically detects a container feature and a sensor interface that interfaces with a sensor that uses a code provided on a retaining-and-centering unit that holds a container to determine a rotational position of that container. A computer connects to the image-capturing device and the sensor unit. The computer determines an alignment variable based on the code and the detected container feature and then forwards this alignment variable to a printer segment on a printer module.