Coordinate Systems in Oasis montaj

Oasis montaj contains a powerful "on-the-fly" projection engine that provides the ability for maps to have several views, each view containing a different coordinate system. In addition, dynamic links between maps and data are maintained, even if different coordinate systems are used.

What Is a Coordinate System?

A coordinate system is a systematic construction of features on a plane surface (a map) to represent corresponding features on a spherical surface (the earth). Coordinate Systems include actual objects (highways, coastlines) as well as constructs (meridians, political boundaries).

How Can I Use Coordinate Systems?

When you are using Oasis montaj, you will be able to display and dynamically link any number of maps regardless of their coordinate system. These maps must have a coordinate system information already defined.

Oasis montaj has simplified the mapping coordinate system process by a redesigned Coordinate System tool. The new one-step process makes creating, editing, or viewing coordinate systems easier. The Coordinate System tool supports ESRI projection files (*.prj), and the projection tables are being periodically updated to the most recent EPSG version.

A map coordinate system defines how geographic coordinates on the earth (longitude and latitude in some datum) are located on a flat mat sheet. When dealing with map coordinate systems, it is important to be aware that the geographic map location (X,Y) of any information is either in an implied or a known map coordinate system. If you do nothing to define the coordinate systems in your data, Oasis montaj will assume that all locations (X,Y) are in the same map coordinate system, which is unknown.

Oasis montaj features "smart projections", which enables the system to project data "on the fly" as it is displayed. This ability enables maps to have several views – each containing a different set of projection coordinates.

Map coordinate systems can be defined for any pair of channels in a database, for a grid coordinate system, and for a data view in a map. In most cases, all that is required is to define the coordinate system of the "X" and "Y" channels of an original database. This coordinate system will then be passed on to grids when data is gridded, and map views will inherit this coordinate system when they are created. Coordinate systems for data channels, grids, and views can also be viewed and modified at any time. However, the modification of map coordinate systems does require specific and accurate knowledge of the specific coordinate system information.