Offset Measurement; Single-Distance Offset Measurement - Sokkia 30R Series Operator's Manual

17. OFFSET MEASUREMENT

Offset measurements are performed in order to find a point where a target cannot
be installed directly or to find the distance and angle to a point which cannot be
sighted.
• It is possible to find the distance and angle to a point you wish to measure
(target point) by installing the target at a location (offset point) a little distance
from the target point and measuring the distance and angle from the surveying
point to the offset point.
• The target point can be found in the three ways explained below.
17.1

Single-distance Offset Measurement

Finding it by entering the horizontal distance from the target point to the offset
point.
• When the offset point is positioned to the left or right of the target point, make
sure the angle formed by lines connecting the offset point to the target point and
to the instrument station is almost 90°.
• When the offset point is positioned in front of or behind the target point, install
the offset point on a line linking the instrument station with the target point.
PROCEDURE
1. Set the offset point close to the
target point and measure the
distance between them, then set
up a prism on the offset point.
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