Leica NA720 User Manual page 19

Compensator
Backsight/Fore-
sight/Intermediate
sight
NA720/724/728/730/730 plus, Description of the System
a
008788_001
The compensator in the instrument is responsible for compensating the vertical axis
tilt enabling an exactly horizontal aiming.
008809_001
For determining the height difference (∆H) between the ground points A and B the
back sight (R) is measured first followed by the forward sight (V). Additional points
relating to A are measured as intermediate sight (S).
b
a) Plumb line
b) Line of sight
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