A sensor device and method of employment is provided. The home node includes a local interconnect, a node controller coupled between the local interconnect and the node interconnect, a home system memory, a memory directory including a plurality of entries, and a memory controller coupled to the local interconnect, the home system memory and the memory directory. An image of the printed test pattern is analyzed to determine a first camera pixel separation between two features printed with the first printhead, which is used to determine a camera scale factor. The PDC portion has a phase-to-digital transfer function that exhibits certain imperfections. When the exposure device is attached to the housing, the light-shielding member is bent by the exposure device into the groove.