Which coordinate system to select when importing Shapefiles into iCMTGIS PRO?

When loading geographic position data into a mapping software program, the program needs to know which coordinate system the position data refers to.

When you import such position data into iCMTGIS PRO, it will display a window for you to specify the datum, coordinate system and distance unit so that it can place the geographic Features (shapes) in the correct map location.

Often the set of Shapefiles that you get comes with a .prj (projection) file. If you include this file with the files you copy to the Documents folder for iCMTGIS PRO, then when you import the Shapefiles, the app will display the proper coordinate system information, and all you need to do is to confirm it. You might want to write down this information if you don’t already know it.

Suppose you knew the reference coordinate system beforehand, and you have set the coordinate system in iCMTGIS PRO to match it before importing the Shapefiles, then the imported data will be displayed using that coordinate system.

On the other hand, if the working coordinate system is different from that used by the Shapefiles, then after the Shapefiles have been imported, the data will be displayed using the working coordinate system.

In other words, when you specify the coordinate system during the import process, it is strictly for use in interpreting the imported data. It does not change the currently active coordinate system.

Therefore, if you did not know the coordinate system information of the Shapefiles, you should write down the information displayed by iCMTGIS PRO during the import process, so that you could switch to that system later, if you wish.

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