The invention contemplates {HEAD ~ a precisely adjustable threaded mechanism}, as for focus adjustment of an aerial camera lens, wherein {TAIL ~ inner and outer threaded members} are normally in circumferentially continuous radially stressed play free engagement to the extent of requiring a characteristic maximum torque for their rotary adjustment 
The invention contemplates { HEAD ~ a precisely adjustable threaded mechanism } , as for focus adjustment of an aerial camera lens , wherein { TAIL ~ inner and outer threaded members } are normally in circumferentially continuous radially stressed play free engagement to the extent of requiring a characteristic maximum torque for their rotary adjustment
OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH