# To measure by angle offset

In a conventional survey, there are three angle offset methods that you can use to observe a point that is inaccessible:

- The Angle offset method holds the horizontal distance from the first observation, and combines this with the horizontal angle and vertical angle from the second observation to create an observation to the offset location.
- The V.Angle offset method holds the horizontal distance and horizontal angle from the first observation, and combines this with the vertical angle from the second observation to create an observation to the offset location.
- The H.Angle offset method holds the slope distance and vertical angle from the first observation, and combines this with the horizontal angle from the second observation to create an observation to the offset location.

All raw observables from the first and second observations are stored in the job file as HA, VA, and SD records and can be exported.

1. Tap and select Measure / Measure topo.
2. Enter the Point name and, if required, the Code.

3. In the Method field, select Angle offset, H. Angle Offset, or V. Angle Offset.

   When using the H.Angle offset measurement method, the target height from the first observation is applied to the horizontal angle offset observation.

   When using Angle offset or V.Angle offset measurement methods you do not need to enter the Target height. The offset measurements are to the offset location and the target height is not used in any computations. To ensure that a target height is not applied to the observation, a target height of 0 (zero) is automatically stored to the software database.

4. If you are using Autolock technology, tap Options and select the Autolock off for offsets check box to automatically disable Autolock for the offset measurement and then re‑enable it after the measurement.
5. Aim the instrument at the target, prism or, if using DR mode, at the object to be measured.

6. Tap Measure.

   The first observation is displayed.

7. Turn to the offset location and then tap Measure. The two observations are combined into one.
8. If you selected the View before storage check box in the survey style, the observation adjusted for the offset distance appears. Tap Store.