Lab II: Point Database Conversions

Lab II Section I: Point Database Conversions - Manual Conversions

Objective:

Use the interactive spreadsheet (Point Database Conversions) to convert a list of coordinates from Geodetic Lat/Long to Universal Transverse Mercator.

The Point Database Conversion function of the Geographic Calculator is designed to handle coordinate conversions in batch mode (i.e. convert many coordinates at once). This exercise will familiarize the user with the basic workings of the Point Database Conversion area.

There are three points to convert. They are stated in Geodetic Lat/Long. They must be converted to Universal Transverse Mercator grid values.

Point 1

44 16 18.72 N

69 46 19.90 W

Point 2

44 18 59.83 N

69 46 43.49 W

Point 3

44 13 36.96 N

69 46 08.11 W

Follow these steps to complete a conversion of these coordinates in the Point Database Conversions area:

Open the Geographic Calculator.
Click on the Point Database Conversions tab to open the interface.
Go to the Point Database Conversions grid.
Right click on the box next to the box marked “C1”.
From the options that appear, click Insert column. This will prompt you to enter a title for the box. The default setting is “C2”.
Click OK. This will create another vertical column titled “C2”.

Hint: It is often beneficial to use meaningful column names to avoid later confusion.

Repeat this process to create another box titled "C3" and "C4".
Select your Input Coordinate System by going to the Source Coordinate System area and clicking on the Define Coordinate System control button.
A dialog box will appear. Select the following parameters:

Group:

Geodetic Latitude/Longitude

System:

Latitude/Longitude

Datum:

WGS84

Select the units for your input coordinate system by going to the Source Coordinate System area and clicking on the Units (center) control button.
A dialog box will appear. Select the following parameter:

Angular Unit:

DEGREES

Select the format for your input points by going to the Source Coordinate System area and clicking on the Format control button.
A dialog box will appear. Select the following parameter:

Input Format:

DD MM SS.

(All other information on this page controls the output display)

Select your Output Coordinate System by going to the Destination Coordinate System area and clicking on the Define Coordinate System control button.
A dialog box will appear. Select the following parameters:

Group:	Universal Transverse Mercator
System:	Zone 19S (72W to 66W)
Datum:	WGS84
Linear Unit:	METERS

Select the units for your output coordinate system by going to the Destination Coordinate System area and clicking on the Units (center) control button.
A dialog box will appear. Select the following parameter:

Linear Unit:

METERS

Select the format for your output points by going to the Destination Coordinate System area and clicking on the Format control button.
A dialog box will appear. Select the following parameter:

Decimal Precision:

Now that the source and destination coordinate systems have been defined you can set up your Conversion Settings.

Initialise the Conversion Settings for your conversion by going to the Point Database Conversion area and clicking on the Conversion Settings control button.
A dialog will appear. Select the following parameters:

Latitude:	C1
Longitude:	C2
North/South:	C3
East/West:	C4

The columns are now ready to have coordinates entered for conversion. Enter the Source coordinates into the columns C1 (North values) and C2 (East values). Enter all three coordinates listed below. Horizontal rows will appear as each set is entered (R1, R2, R3, ...). (Note: The values may appear to be truncated in the cells of the spreadsheet. The columns widths may be increased by dragging a column boundary with the mouse pointer to the desired width—note the position of the pointer between C1 and C2 in the image below. Formatting options (text schemes) are discussed in more detail in the next section)