Convert Coordinate Systems
Summary
An EPSG-based (European Petroleum Survey Group) coordinate converter introduces industry-standard coordinate conversions to Micromine. Although we expect this new tool to become the main coordinate conversion method, we recognise that during the transition period, the duplicated options (which all do much the same thing) may be confusing for inexperienced users. This summary explains the differences between the conversion options.
The Survey menu icurrently includes three generations of coordinate conversions, which all use different algorithms and parameters:
Third generation
Released 2018
- Convert Coordinates Between | Setup
- Convert Coordinates Between | Coordinate Systems (Keyboard)
- Convert Coordinates Between | Coordinate Systems (File)
- Convert Coordinates Between | Coordinate Systems (Wireframe)
Second generation
Released 2010
- Convert Coordinates Between | Coordinate Systems
First generation
Released c.1998
- Convert Coordinates Between | Geographic and (U)TM
- Convert Coordinates Between | Datum (Molodensky)
We recommend always using the third generation coordinate conversion because it:
- Supports all forms of coordinate conversion.
- Is easier to set up than the second-generation version.
- Has no limitations on the number of available coordinate systems.
- Is the only conversion method to support shift grids (also known as difference grids or distortion grids) for high-precision datum conversions.
However, should you need to use one of the older methods, this matrix will help you to decide how to proceed.
|
Conversion / Generation |
Generation 3 |
Generation 2 |
Generation 1 |
|
Geographic to/from Projected |
|
|
(a) |
|
Geographic to/from Local Grid |
|
|
|
|
Datum conversion (legacy) |
|
(c) |
(b) |
|
Datum conversion (high precision) |
|
|
|
|
Supported |
Limited |
Not supported |
(a) Geographic and (U)TM only supports Transverse Mercator (TM)-based coordinate systems. User must supply TM parameters.
(b) Datum (Molodensky) uses low-precision algorithm and parameters. Still the state of the art in some regions.
(c) Coordinate Systems uses medium- to low-precision algorithms. User must supply parameters, which can be confusing for inexperienced users, and hard to obtain.
Modern geospatial data are defined in numerous coordinate systems from around the world, which can complicate the process of combining them into a single view. A typical example involves converting government data (in latitude/longitude coordinates) to the working coordinate system of your project; another is converting historic data on an old geodetic datum to a modern geocentric datum.
Micromine’s Coordinate System Conversion options support virtually any pair of coordinate systems. Most conversions are between recognised coordinate systems, and Micromine uses the EPSG (European Petroleum Survey Group) database to supply the parameters for well over 5000 coordinate systems and their conversions. Micromine also supports the high-precision distortion grid methods (also known as shift or difference grids) required by modern datums.
To convert between coordinate systems, select the Coordinate Transform tab.
The process takes place in two stages:
- Define the conversion by choosing the origin and destination coordinate systems. This happens only once, and typically takes just a few seconds.
- Use it to convert your coordinates.
Once the conversion is defined, you can convert DATA (and related) files, wireframes, interactively via the relevant dialogs. This setup-once, use-many-times philosophy hides the conversion details and ensures that you always use the same parameters every time you run that conversion.