Spectra Geospatial Focus 35, Руководство пользователя

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6 Instrument Technology
Correction for Trunnion Axis
The trunnion axis tilt error is the deviation of the trunnion axis of the telescope from its required position
at right angles to the plumb axis of the instrument.
In the FOCUS 35 Total Station, perform a pre-measurement trunnion axis tilt test to determine the
trunnion axis tilt error. Angular measurements are observed in both instrument faces, the trunnion axis
tilt error is calculated, and the respective correction value is stored in the instrument. The trunnion axis
tilt correction value is then applied as a correction to the horizontal angle value.
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Carry out a trunnion axis tilt test in the following situations:
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Whenever the instrument may have been roughly handled during transport.
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When the ambient temperature differs by more than 10 °C (18 °F) from the previous collimation test.
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Immediately prior to high precision angle measurements in one face.
Averaging Measurements to Reduce Sighting Errors
The FOCUS 35 Total Station automatically reduces sighting errors caused by the misalignment of the
instrument to the target or by pole movement during measurement.
The following techniques can be used:
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Use LockNGo Tracker. When LockNGo Tracker is enabled, the instrument automatically locks onto
and tracks the target. Manual sighting errors are reduced.
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Automatically average angles during distance measurement. When measuring in Standard mode,
the instrument takes angle measurements while measuring the distance. Angles returned to the
instrument at 200 Hz, are averaged over this period to obtain an averaged angle measurement.
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Use average measurement methods in the field software.
FOCUS 35 Total Station User Guide | 89