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Conventional Observations

These are measurements performed with a total station. The total station consists of a theodolite that measures angles and a built-in electronic distance meter.

With a total station, we can measure horizontal direction, slope distance, and vertical angle.

Below we see what the various symbols on the screen mean:

  • Horizontal direction
  • Distance and horizontal direction
  • Distance, horizontal direction and vertical angle

Manual edits:

  • Angle is modified
  • Angle is excluded
  • Distance is modified
  • Distance is excluded

Conventional Station

A station in Gemini is the setup point for a measured half set. Station points can be a benchmark (known point) or a point determined with control (adjustment point), for example free station.

Example of free station setup

One set in Gemini Terrain = one station = one half set.

A station contains instrument number and instrument height, correction code, pressure and temperature. These are therefore common to all observations in this station.

Rules for Set Measurement

We import observations in a common structure via the field book module. Then Gemini will interpret the observation pattern automatically as the default setting. This means that all formats are in principle supported by the interpretation.

Note

We must have an equal number of sights in each set.

If we have not measured sets or for other reasons do not want to interpret the pattern for set measurement, we can choose this. For example, sights for station establishment, depending on how these are performed, can "disturb" the interpretation.

Supported Patterns

Measurement method ABC…ABC

(Series, first telescope position I for all observations, then telescope position II)

Example: A1B1C1 A2B2C2

Stations in Gemini:

Station1: A1B1C1D1 Station2: A2B2C2D2

Can have more than 2 series.

Measurement method ABC…CBA

(Series reversed)

Example: A1B1C1D1 D2C2B2A2

Stations in Gemini: Station1: A1B1C1 Station2: C2B2A2

Measurement method ABC/ABC

(Telescope position change for each observation, telescope position I/telescope position II to first point, telescope position I/telescope position II to second point and so on)

Example: A1A2B1B2C1C2 There can be more than two telescope position changes.

Stations in Gemini: Station1: A1B1C1 Station2: A2B2C2

Measurement method ABC/ABC

(Series with telescope position change)

Example: A1A2B1B2C1C2 A3A4B3B4C3C4 Can have more than 2 series.

Stations in Gemini: Station1: A1B1C1 Station2: A2B2C2 Station3: A3B3C3 Station4: A4B4C4

Measurement method ABC/ABC

(Series with telescope position change reversed)

Example: A1A2B1B2C1C2 C3C4B3B4A3A4 Can have more than 2 series.

Stations in Gemini: Station1: A1B1C1 Station2: A2B2C2 Station3: C3B3A3 Station4: C4B4A4

If we import observations without automation, all observations in a setup will end up on the same station ID. We can then perform the set interpretation manually and use other functions to organize the measurements.

We refer to the dialog help for conventional observations for further description.