GeoMax Zoom95 Series - Zenith, Crosshairs, and Error Definitions; Zenith and Crosshairs Definitions; Line-of-Sight Error (Horizontal Collimation); Vertical Index Error Definition

Point on the plumb line above the observer.
Glass plate within the telescope with reticle.
TS0X_005
c
The line-of-sight error (c) is the deviation from the perpendicu-
lar between the tilting axis and line of sight. This could be elimi-
nated by measuring in both faces.
i
TS0X_006
With a horizontal line of sight the vertical circle reading should
be exactly 90°(100 gon). The deviation from this value is
termed the Vertical index error (i).
Zenith
Crosshairs
Line-of-sight error (hori-
zontal collimation)
Vertical index error
68 Glossary