Reticle Cross-Line (Line Of Sight) - Sokkia C300 Operator's Manual

7.3 RETICLE CROSS-LINE (LINE OF SIGHT)

1) Set the instrument halfway between two points, A
and B, 30 to 50m apart. Take readings a1 and b1.
(Fig.7.5)
2) Set the instrument at a point 2 m from point A.
Take readings a
Leave the telescope sighted on point B.
Calculate
b ' = a
2
If b ' = b
2
normal and no adjustment is necessary.
When b
the cross-line as follows:
2
- (a - b
2 1 1
, the horizontal cross-line is
2
' and b
2 2
Fig.7.5
and b . (Fig.7.6)
2
Fig.7.6
)
are different, adjust
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