Leica TS11 User Manual page 74

TS11/TS15, Operation
Caution
ATR/lock
If using the long range measurement mode (> 1000 m, > 3300 ft) to prisms, and an
object passes within 30 m of the EDM as the measurement is triggered, the distance
measurement may be similarly effected due to the strength of the laser signal.
Very short distances can also be measured reflectorless in Prism mode to well
reflecting natural targets. The distances are corrected with the additive constant
defined for the active reflector.
Due to laser safety regulations and measuring accuracy, using the Long Range Reflec-
torless EDM is only allowed to prisms that are more than 1000 m (3300 ft) away.
Accurate measurements to prisms should be made in Prism mode.
When a distance measurement is triggered, the EDM measures to the object which is
in the beam path at that moment. If a temporary obstruction, for example a passing
vehicle, heavy rain, fog or snow is between the instrument and the point to be meas-
ured, the EDM may measure to the obstruction.
Do not measure with two instruments to the same target simultaneously to avoid
getting mixed return signals.
Instruments equipped with an ATR sensor permit automatic angle and distance meas-
urements to prisms. The prism is sighted with the optical sight. After initiating a
distance measurement, the instrument sights the prism centre automatically. Vertical
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