An evaluation value which includes at least one of a luminance and a high frequency component of {TAIL ~ the images} obtained by the imaging units at {HEAD ~ the predetermined time interval} is calculated 
An evaluation value which includes at least one of a luminance and a high frequency component of { TAIL ~ the images } obtained by the imaging units at { HEAD ~ the predetermined time interval } is calculated
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH