The spectral image may be a three dimensional image that provides spectral intensity values for each of a number of wavelengths at each of a number of {HEAD ~ positions} within {TAIL ~ a two dimensional image plane} 
The spectral image may be a three dimensional image that provides spectral intensity values for each of a number of wavelengths at each of a number of { HEAD ~ positions } within { TAIL ~ a two dimensional image plane }
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL