FOCUS 35 TOTAL STATION USER GUIDE
4 –
Setup
76
Instrument height measurement
The measured distance (Hm) is corrected for the slope of the measurement to obtain a vertical
measurement to the bottom mark (Hc). The constant from the bottom mark to the top mark
(0.158 m/0.518 ft) is added to the Hc to obtain the vertical instrument height from the ground mark
to the trunnion axis (Ih). For more information, refer to the Spectra Precision Survey Pro
documentation.
Alternatively, to obtain an accurate measurement to the top mark (Ih), you can manually measure
the slope distance from the ground to the bottom mark (Hm). To calculate the total instrument
height (Ih), insert the measured slope distance (Hm) into the formula below:
0.158m
(0.518ft)
Hm
Hc
Ih