FIG 4 illustrates {HEAD ~ a graph} representing distorted radii 405 as {TAIL ~ a function} of the half view angle compared with undistorted radii 410 
FIG 4 illustrates { HEAD ~ a graph } representing distorted radii 405 as { TAIL ~ a function } of the half view angle compared with undistorted radii 410
OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH