obtaining quantized two dimensional image data including {HEAD ~ an object} to be in {TAIL ~ focus} with respect to an optical system by imaging the object through the optical system 
to be in
obtaining quantized two dimensional image data including { HEAD ~ an object } to be in { TAIL ~ focus } with respect to an optical system by imaging the object through the optical system
OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD REL REL REL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH