In this example we add a coordinate system to the Favorite Coordinate Systems list.
We open any drawing or image. We do this to gain access to the coordinate picker button in the Component tab of the Info pane that will provide menu access to the Favorites choice we need to launch the Favorite Coordinate Systems dialog. If we want to specify a new favorite but not actually change the coordinate system of any component we can specify the favorite and then exit the process without changing the coordinate system of the drawing or image that was opened.
For this example we will open the image of Florida terrain elevation data used in the Example: Change Projection of an Image topic. We will follow a process of choosing a new projection like that shown in the example topic.
With the focus on the opened Florida image, in the Component tab of the Info pane click the coordinate system picker button for the Florida layer and click Reproject Component.
In the Reproject Component dialog we click the coordinate system picker to launch the dropdown menu:
In the menu, we choose Favorites , to launch the Favorites dialog that allows us to manage our favorite coordinate systems. The dialog opens with the two, factory default favorite coordinate systems in the list.
We click the Add button to add a new favorite coordinate system to the list. That launches the full Coordinate System dialog that allows us to choose from thousands of systems or to create a custom system.
We click the Custom tab since the coordinate system we want to save as a favorite will be an Orthographic projection centered on Florida.
Since we would like our saved favorite to have a more memorable name than "Custom Coordinate System" we enter the Name of Florida Orthographic. For a Base we choose World Geodetic 1984 (WGS84). We enter the Center latitude of 29 and the Center longitude of -82, the lat/lon of Ocala, Florida, which we reckon to be close enough to the center for how we will be using this projection. We press OK.
Back in the Favorites dialog we see that the new coordinate system has been added to the list of favorites. We press OK.
That brings us back to the Reproject Component dialog
At this point we have added another favorite coordinate system to our Favorites list. If we do not want to change the projection of the Florida terrain data set, we simply press the Close button. If we would like to reproject the image, we proceed with this topic.
We again click the coordinate system picker button.
In the resulting menu we now see the Florida Orthographic custom projection we added to our favorites. We click that to choose it.
Like magic, the Florida Orthographic coordinate system is specified as the New coordinate system. To change the projection and copy the data into a new component using the changed projection we press Add Component.
That creates a new image, called Florida 2 and an accompanying table in the Project. We can double-click open the new Florida 2 image.
We see the new image is as yet not styled. That's easy to fix as shown in the Example: Change Projection of an Image topic.
The new image shows the terrain a bit narrower, a typical effect of Orthographic centered upon Florida given that the original Latitude / Longitude projection shows the terrain a bit wider than it would look when seen in real life from space.
Synonyms - Cartographers favor the term projection while programmers seem to prefer coordinate system. This documentation uses the two terms interchangeably, with the term projection tending to be used more in GIS or display contexts and the term coordinate system tending to be used more when discussing programming, SQL or standards.
Info Pane: Component
Assign Initial Coordinate System
Base Coordinate System
Favorite Coordinate Systems
Favorite Base Coordinate Systems
Example: Convert a 0 to 360 Degree Projection - We often encounter data, both images and drawings, using latitude and longitude degrees that appears to be in Latitude / Longitude projection but which has longitude values from 0 degrees to 360 degrees and latitude values from 0 degrees to 180 degrees, instead of the usual arrangement of -180 degrees to 180 degrees for longitude centered on the Prime Meridian, and -90 degrees to 90 degrees for latitude centered on the Equator. This example shows how to utilize such data by assigning the correct projection.
Example: Change Projection of an Image - Use the Reproject Component command to change the projection of an image, raster data showing terrain elevations in a region of Florida, from Latitude / Longitude to Orthographic centered on Florida.
Reprojection Creates a New Image - Why changing the projection of an image creates a new image.
About Coordinate Systems