This week's new feature series is a tutorial on how to use the new coordinate system dialogs in MapViewer 8! If you've used Surfer 12, Didger 5, or Strater 4, the Assign Coordinate System dialog may look familiar, only with a few new perks added! In MapViewer 7, you could access the Map Projection options dialog by clicking the Map | Convert Projection, Map | Calibration, or Tools | Reproject Data File commands, or when importing or creating a map using files with an unknown projection. In MapViewer 8, the Assign Coordinate System dialog can also be accessed from several different places. Most often, the dialog will be accessed by clicking the Change button on the Coordinate System page of the Property Manager. However, this dialog may also be accessed by clicking the Map | Plot | Calibrate command, when adjusting the input or output coordinate system when reprojecting data files with the Home | Data | Reproject Data File(s) commands, or when importing or creating a map using files with an unknown projection.
Coordinate system dialogs
The image above shows the Assign Coordinate System dialog and the two dialogs that can be opened from it, the Define Unreferenced Coordinate System dialog and the Define Coordinate System dialog. Let's go over what each of the buttons in the Assign Coordinate System dialog does.
Search and Clear Search
Currently exclusive to MapViewer 8, don't spend time reading long lists of coordinate systems to find the one you want! Search for a specific coordinate system by typing text or EPSG codes into the Search for text or EPSG code search bar and clicking the Search button or by pressing the ENTER key on the keyboard. The dialog will display the number of results and list them in the coordinate system list. Click the Clear Search button to remove a search filter from the coordinate systems list and view all coordinate systems.
New Local System
Clicking the New Local System button opens the Define Unreferenced Coordinate System dialog. In this dialog, you can define your own custom local system. You can give the coordinate system a Name, select the unit of measure for the coordinate system, modify the Units per meter to create a unit of measure not in the Name list, and adjust the X and Y Offset. Click OK, and the coordinate system is added to the Custom list.
New Geographic System
Click the New Geographic System button to open the Define Coordinate System dialog. Here, you can define a new custom geographic system. Enter a Name, select a predefined Projection from the dropdown list, enter the projection Parameters, and specify a Datum. If desired, modify an existing Datum to create a custom one! Click OK, and the coordinate system is added to the Custom list.
The Define Coordinate System dialog also opens when you select a predefined coordinate system and click the Modify button. Use this dialog to make any desired modifications to an existing coordinate system. Give the new custom coordinate system a Name, and click OK to add the coordinate system to the Custom list.
Add to Favorites and Remove from Favorites
Select an existing coordinate system from the coordinate system list, and click the Add to Favorites button to add the coordinate system to the Favorites list. Save time by having your most used coordinate systems at your fingertips! You can add predefined or custom coordinate systems to the Favorites list! In fact, I recommend adding any custom coordinate systems you'd like to access for future projects to the Favorites list, so they're always readily available! Otherwise, the custom coordinate system is only available when the file using that coordinate system is open. Select a coordinate system in the Favorites list, and click the Remove from Favorites button to remove it from the Favorites list.
OK and Cancel
Click OK to apply any changes and close the dialog, and click Cancel to exit the dialog.
Now that we've discussed what each button does. Let's take a look at the coordinate system list to see what it contains!
Coordinate system list
The image above shows the coordinate system list. Double-click a section (or click the + sign) to expand the section and see what it contains! For example, to navigate to the Eckert IV Projection coordinate system, double-click Predefined, then Projected Systems, then World, and then click Eckert IV Projection. Below is a discussion of what is contained in each section of the list.
Local System contains the Unreferenced local system coordinate system. This option is appropriate if your map uses an arbitrary coordinate system that does not contain real world coordinates. The Unreferenced local system contains a Projection of None, a Datum of None, and a Warp of None.
The Predefined section lists all the predefined coordinate systems that MapViewer 8 supports, including templates ready to use to create custom coordinate systems! The Geographic (lat/lon) subsection contains unprojected latitude and longitude coordinate systems and datums. One of the options in this list may be appropriate if your data is in latitude and longitude format. The Projected Systems subsection contains many projected systems, many of which have their own subsections! In this list, you'll find commonly used coordinate systems such as UTM, State Plane, and other commonly used projected coordinate systems from around the world. Lastly, the Templates subsection contains predefined templates using nearly each of the supported projections! Click on a template, and click the Modify button to use the template to create a custom coordinate system. The new coordinate system will be added to the Custom section.
The Favorites section lists all the coordinate systems you have added to the Favorites list. Favorites are a great way to keep commonly used coordinate systems convenient to your workflow. Additionally, custom coordinate systems are only available when the file using that coordinate system is open. To always have access to the custom coordinate system, add it to your Favorites list!
Finally, the Custom section lists any custom coordinate system in use by a currently open file. Add it to the Favorites list so it's always available!
I hope you've enjoyed this guide to the coordinate system dialogs in MapViewer 8! Stop by next week for the conclusion of the MapViewer 8 new features series, a look at new options for legends!
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Eckert IV projection image from Wikimedia. The Creative Commons license can be viewed here.