Under processor control, the color measurement may be made at {HEAD ~ a predetermined height} and {TAIL ~ angle} 
Under processor control , the color measurement may be made at { HEAD ~ a predetermined height } and { TAIL ~ angle }
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH TAIL TAIL TAIL TAIL TAIL