Tripod Data Systems SURVEY PRO User Manual page 229

• Pick from Data Base. Select this choice to use a datum from
the coordinate system database.
• Custom Molodensky. Select this choice to enter a custom
three-parameter datum transformation.
•
Custom Similarity. Select this choice to enter a custom seven-
parameter datum transformation.
3. Select the Azimuth type for the new map projection zone. Choices
are:
•
North Azimuth. Select this choice to have a north azimuth grid.
• South Azimuth. This choice to have a south azimuth grid.
4. Select the Grid direction for positive coordinates in the new map
projection zone. Choices for grid direction are:
• North\East Grid. Select this choice to have coordinates increase
positive in the north and east directions.
• South\West Grid. Select this choice to have coordinates
increase positive in the south and west directions.
Note: The geodetic calculation engine and the Survey Pro coordinate
geometry engine are separate components. While the geodetic engine
can properly handle southwest grid systems, Survey Pro can only
operate on a northeast grid system. However, since a southwest grid
with a south azimuth is a mirror image of a northeast grid with a
north azimuth, Survey Pro can handle this configuration with the
following work around: You must set the Azimuth Type to North
Azimuth on the Units card of the Job, Settings screen. You then treat
north as south and east as west, and the coordinates will be correct
for a southwest grid and south azimuth zone.
5. Tap Next to enter the zone parameters for the new map
projection.
6. Key in the five or six parameters for your new map projection
zone.
7. If your zone is Oblique Mercator Angle, the next screen is used to
pick the Origin and Azimuth values.
GPS Coordinates in Survey Pro
219