Distance Measurement; Returned Signal Checking - Sokkia im-101 Operator's Manual

12.DISTANCE MEASUREMENT

Perform the following settings as preparation for distance measurement.
• Distance measurement mode
• Target type
• Prism constant correction value
• Atmospheric correction factor
• EDM ALC
"33.1 Observation Conditions - Angle/Tilt"/"33.2 Observation Conditions - Dist"

Caution
• When using the Laser-pointer function, be sure to turn OFF the output laser after distance measurement is
completed. Even if distance measurement is canceled, the Laser-pointer function is still operating and the
laser beam continues to be emitted. (After turning ON the Laser-pointer, the laser beam is emitted for 5
minutes, and then automatically switches OFF. But in the Status screen and when target symbol (ex. ) is not
displayed in the OBS mode, the laser beam is not automatically turned off.)

• Make sure that the target setting on the instrument matches the type of target used. iM automatically adjusts
the intensity of the laser beam and switches the distance measurement display range to match the type of
target used. If the target does not correspond to the target settings, accurate measurement results cannot be
obtained.
• Accurate measurement results cannot be obtained if the objective lens is dirty. Dust it off with the lens brush
first, to remove minute particles. Then, after providing a little condensation by breathing on the lens, wipe it
off with the silicon cloth.
• During reflectorless measurement, if an object obstructs the light beam used for measurement or an object
is positioned with a high reflective factor (metal or white surface) behind the target, accurate measurement
results may not be received.
• Scintillation may affect the accuracy of distance measurement results. Should this occur, repeat
measurement several times and use the averaged value of the obtained results.

12.1 Returned Signal Checking

Check to make sure that sufficient reflected light is returned by the reflective prism sighted by the telescope.
Checking the returned signal is particularly useful when performing long distance measurements.

Caution
• The laser beam is emitted during returned signal checking.

• When the light intensity is sufficient even though the center of the reflective prism and the reticle are slightly
misaligned (short distance etc.), "*" will be displayed in some cases, but in fact, accurate measurement is
impossible. Therefore make sure that the target center is sighted correctly.
PROCEDURE
1. Allocate the [S-LEV] softkey to the OBS mode screen.
"33.12 Allocating Key Functions"
2. Accurately sight the target.
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