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Data Frame coordinate system different from data projection

March 23 2009 | 1 comment
Categories: ArcGIS Methods, Map Elements

I'm starting a new mapping project using our corporate data (stored in UTM projection). The data frame for the map series will have a UTM projection but the data frame boundary will be geographical (i.e., a 2-degree lat/lon system). What are the procedures to set up this type of project? Are there any handy tips? I'm sure I'm not the only person who would like to see some procedures/advice on this subject. Many thanks.

Mapping Center Answer:

What you're looking for is a grid (we loosely shortened our internal term of "Map Grid" for the user interface) for your data frame.  In the help we called these reference systems*.  There are three kinds of grids or reference systems:

1.  Graticule (what you're asking for), which displays latitude and longitude coordinates.

2.  Measured Grid, which displays the coordinates of a coordinate system that you choose (could be UTM, or here in the U.S., State Plane).

3.  Reference Grid, which comes from a polygon dataset; typically these are custom or historical grids.

To add a grid to your data frame, open the data frame's properties and click on the Grids tab.  Click the New Grid button to launch the wizard (default option; if you've turned off Wizard mode in the Options dialog [Tools -> Options -> General tab], you'll see a style selector with the grids in your referenced styles).

You can have more than one grid on your data frame, so you could have a lat/lon grid (graticule), a UTM grid (measured grid), and the Tasmanian Map Boook Grid Index (reference grid) all on the same data frame.  Granted that would warrant a bit of design to decide how to differentiate them, and whether to show grid lines on the map, etc.

*The use of the terms grid and graticule is not universally agreed upon when it comes to defining whether a graticule is a special kind grid. Reference System turned out to be a conveniently neutral term.  Measured grid, as a term wasn't all that widely used when we found it years ago; but it concisely fit more situations than something like Standard Grid Coordinate Systems, which were easily confused because some are less standard, and there were already too few people who knew the differences between projected, geographic, and grid coordinate systems.


Rotating the frame posted by Guillaume Criloux on Aug 4 2009 2:53AM
If the frame limits are based on geographic coordinates (meridians and parallels), then you will have to rotate the frame provided that you want the map frame to be parallel to the paper sheet.
This angle named the grid convergence is to be calculated. Any hint to do it easily inside ArcMap ?

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