Spectra Precision Focus 6, User Manual

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2
Setting up the Instrument
34
Spectra Precision Focus 6 5" Total Station User Guide
•
When measuring a short distance, incline the prism slightly so that the EDM
can ignore unnecessary reflections on the prism surface, as shown below.
•
Hold the prism securely in place and do not move while taking measurements.
Note – In Prism mode, to avoid false measurements on objects other than the prism or
reflector-sheet, targets that are less reflective than the prism or reflector sheet are not
measured. Even if you start a measurement, measured values are not displayed. To
measure less reflective objects, use the N-Prism (Reflectorless) mode.
Measurement in reflectorless (N-Prism) mode
The Focus 6 5" total station enables reflectorless measurements up to 300 m (984 feet).
The intensity of the reflection from the target determines the distance the Focus 6 5’’
total station can measure in this mode. The color and condition of the target surface
also affect the measurable distance, even if the targeted objects are the same. Some
less-reflective targets may not be measured.
The following table describes some examples of targets and approximate measuring
distances:
Measurable distances may be shorter or measurement intervals may be longer if either
of the following conditions apply:
•
the angle of the laser against the target is small
•
the surface of the target is wet
In direct sunlight, the measurable distance may be shorter. In this case, try to throw a
shadow on the target.
Targets with completely flat surfaces, such as mirrors, cannot be measured unless the
beam and the target are perpendicular to each other.
Target You can measure approximately...
Traffic signs, reflectors 500 meters (1640 feet)
Paper (white), veneer (new) 300 meters (990 feet)
Wall (brightly painted), brick 100 to 200 meters (330 to 660 feet)
Not completely square to
the sighting axis
Completely square to
the sighting axis
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