Quick Tips for Using COLUMBUS

UTM and TM Coords

• Calculating UTM or TM coordinates following a 2D/3D Geodetic adjustment
  
  
• Calculating UTM (Universal Transverse Mercator) or TM coordinates from Geodetic coordinates and Geodetic coordinates from UTM (or TM) coordinates
  
  
• Creating a custom Transverse Mercator (TM) Projection not supported directly in COLUMBUS

Calculating UTM or TM coordinates following a 2D/3D Geodetic adjustment

For the quickest way to calculate UTM or TM coordinates following a 2D/3D geodetic adjustment, do the following:

1. Load your network into COLUMBUS.

2. Set up your UTM or TM Zone, if not already done (from the Options | Projection Zones | UTM Zone Setup).

3. Perform your network adjustment (see the Quick Tip topic, Network adjustment in six steps).

4. From the Results menu, select the Adjusted Network View. This will set the context for using the current adjusted geodetic coordinates.

5. From the Tools menu, select Transformation | UTM <--> Geo.

6. Click the Compute button and select the stations you wish to transform by clicking on the station name(s).

7. To keep the newly computed coordinates into memory (so they can be saved to a COLUMBUS input file, exported or used in another area of COLUMBUS), click the Keep button.

Hint: Before exiting COLUMBUS, save the station data to a COLUMBUS data file for future use.

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Calculating UTM (Universal Transverse Mercator) or TM coordinates from Geodetic coordinates and Geodetic coordinates from UTM (or TM) coordinates

To calculate UTM (or TM) coordinates from/to geodetic coordinates, do the following:

1. Run COLUMBUS.

2. From the File menu, select New.

3. From the Options menu, select Datums and select the datum to be active.

4. From the Options menu, select Projection Zones | UTM Zone Setup.

5. Enter the Central Meridian, Scale Factor, False Easting and False Northing.

6. Click OK.

7. From the Data menu, select Stations.
   • For Geodetic to UTM (or TM):
     1. Select the Geodetic grid and enter the geodetic coordinates for each station.
     2. Click Keep and Exit.
     3. From the View menu, select either 2D Geodetic or 3D Geodetic.

   • For UTM (or TM) to Geodetic:
     1. Select the UTM grid and enter the UTM (or TM) coordinates for each station.
     2. Click Keep and Exit.
     3. From the View menu, select 2D or 3D UTM.

8. From the Tools menu, select Transformation | UTM <--> Geo..

9. Click the Compute button and select the stations you wish to transform by clicking on the station name(s).

10. To keep the newly computed coordinates into memory (so they can be saved to a COLUMBUS input file, exported or used in another area of COLUMBUS), click the Keep button.

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Creating a custom Transverse Mercator (TM) Projection not supported directly in COLUMBUS

Use this option if your TM projection does not have its origin at the equator.

COLUMBUS can support just about any Transverse Mercator Projection. You simply need to set up the custom zone parameters in the Projection Zones | State Plane Zones dialog.

1. Run COLUMBUS.

2. From the File menu, select New.

3. From the Options menu, select Projection Zones | State Plane Zones.

4. From near the top of the list, select UD Transverse Mercator (user-defined Transverse Mercator).

5. Click OK. A new dialog box will appear in which you must enter the parameters for the projection.
   • Latitudes should always be positive in the northern hemisphere.
   • Longitudes are positive in the eastern hemisphere.

   Click on the Help button for more information.

6. Click OK.

The customized TM zone is now configured and active. To use this zone, follow the data entry and computational steps described in the Quick Tips - State Plane Coords page.