Spectra Precision Survey Pro v4.6 Ranger User Manual - Manual (Page 246)

User’s Manual – GPS Mode
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Coordinate System Database
Survey Pro uses a Coordinate System Database file (*.CSD) to store
the map projection and datum transformation parameters for many
different coordinate systems around the world. Also, horizontal and
vertical localization adjustments can be stored as site records in the
database. Below is a list of the terminology used to describe the
different records in the coordinate system database.
• Zone: Is the basic record type. A zone record specifies the
type of map projection and its parameters. Usually there is a
datum, ellipsoid, and geoid record from the database already
attached to the zone.
• Site: Is a zone record with a horizontal and/or vertical
localization adjustment added. Localizations are usually used
to correct GPS positions starting from an autonomous base.
They can be computed from control points or from manual
input of parameters. Coordinate systems with Ground
Coordinates set are also site records. A Ground Coordinates
site record may or may not have a horizontal and/or vertical
localization adjustment.
• Zone Group: Is a collection of zone and/or site records used
to keep the database organized and user selection easier.
• Datum: Is a type of datum transformation and its
parameters. There is always an ellipsoid record from the
database already attached to the datum.
• Ellipsoid: Are the two parameters specifying the ellipsoid of
the datum.
• Geoid: Is a geoid model and its associated data file.