{HEAD ~ Shutter gain} according to {TAIL ~ the present invention} accordingly can be increased monotonically from zero to a user settable shutter gain level threshold 
according to
{ HEAD ~ Shutter gain } according to { TAIL ~ the present invention } accordingly can be increased monotonically from zero to a user settable shutter gain level threshold
HEAD HEAD HEAD HEAD HEAD HEAD REL REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH