Chapter 8
8.5
Topography Observations
Averaging Multiple Observations When you use the topography program to observe a previously observed point or a point already known to the SRX, you are shown the difference between the observation and the observation expected by SRX based on its data. For example, you may see a screen like the following, where an asterisk (*) indicates a value that exceeds the tolerances specified in the Tolerance menu.
Please refer to Figure 6 for more information about the values listed on the screen. The ΔSDist field shows the difference in slope distance AB and the distance AB'. The ΔAzmth field shows the difference between the azimuth from A to B and the azimuth to the observed point B'. The ΔVang field (not illustrated) shows the difference between the expected and observed vertical angles. The Pt-Pt SDist field (not illustrated) displays the slope distance between B and B'. Coordinate the SRX already knows
B
Actual observed position B'
Observation that SRX expects ΔSDist ΔAzmth A
Figure 6: Comparing previous data and current observation
After your observation follow these steps: 1.
Select the desired option in the Action field by pressing {} or {}.
The available options are as follows and are described in the following sections. (Some of these options may not be available if they are not relevant.)
8-12
SRX