How do I add Reference Systems (CRS) to Cartographica?

Cartographica has extensive internal capabilities to project and reproject data between different coordinate systems, and comes with a substantial database of commonly-used Coordinate Reference Systems (also known as Spatial Reference Systems and often called Projections).

However, there are times when the CRS that you need is just not available from the set built in to Cartographica.   In these cases, you can easily add new CRS into the User Defined section of Cartographica in order to easily use these reference systems later.

The first chore is finding the CRS in a format that Cartographica can handle.   Fortunately, Cartographica can accept definitions in OGC WKT format, Proj4 format, or most ESRI .PRJ files.    We will concentrate on using the ESRI .PRJ files, as they have the easiest workflow.

Often, you can find the particular CRS you are looking for from online resources, such as the fine site SpatialReference.org.

Here are the basic steps to adding a new CRS to your copy of Cartographica using .PRJ files:

1. Go to SpatialReference.org (or obtain the PRJ file from another source, such as an existing SHP file) 
2. Find a reference system that fits your needs (take care to look for specific zones and units)
3. From the detail page, click on the .PRJ File link, which will download the .PRJ file to your hard drive
4. In Cartographica, select the layer you need to change, and choose Map > Project Map,  Layer > Set Layer's Projection... or Layer > Reproject Layer... depending on what you are trying to do
5. Now drag the .PRJ file that you downloaded in step 3 into the list on the left of the Projection panel.  Cartographica will show it's acceptance with the familiar green + as you drag it in and will add the SRS to the User Defined section
6. You may now select your new CRS and click Set to make the change you desire

Once it's added to the User Defined section, it will remain there until removed using the (-) button.