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I have a layer of plot features in ArcGIS 9.3 that I want the UTM coordinates for. So I used the Feature to Point tool and then added XY coordinates to each point. I then viewed the Attribute table and noticed the coordinates don't make sense.

Here is the information about my map/projection:

Projected Coordinate System:    NAD_1983_StatePlane_North_Carolina_FIPS_3200_Feet
Projection: Lambert_Conformal_Conic
False_Easting:  2000000.00261667
False_Northing: 0.00000000
Central_Meridian:   -79.00000000
Standard_Parallel_1:    34.33333333
Standard_Parallel_2:    36.16666667
Latitude_Of_Origin: 33.75000000
Linear Unit:    Foot_US

Geographic Coordinate System:   GCS_North_American_1983
Datum:  D_North_American_1983
Prime Meridian:     Greenwich
Angular Unit:   Degree

I realize the units are in feet (and I ultimately want meters for UTM), so I converted my X and Y to meters by multiplying each value by 0.3048 in an excel spreadsheet.

The resulting units end up in the Pacific Ocean (they're supposed to be in NC in the U.S.).

Examples of my coordinates (from ArcGIS, so they're in feet):

X Coord              Y Coord
2008821.00994000000  823231.18663500000
2008796.70771000000  823457.50968900000

...converted to meters:

X Coord      Y Coord
612288.6438  250920.8657
612281.2365  250989.849

What am I missing here?

I'm an ArcGIS novice.

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  • You need to reproject to obtain meters in UTM. Multiplying by 3.something should just shift values into the Atlantic (you seem to have multiplied by 0.3...)
    – Vince
    Dec 3 '15 at 20:17
  • The units are US survey feet, not international foot, so you'd have to divide by 3.28083333333333 instead. As Vince says, you'll want to use the Project Tool to create a new feature class in UTM.
    – mkennedy
    Dec 3 '15 at 20:18
  • @mkennedy: Multiplying by 0.3048 and dividing by 3.2808 should give roughly the same values because they are just the inverse of each other. Dec 3 '15 at 20:20
  • Well, yeah, roughly. The inverse of the value I gave is 0.3048006096. When you're working with coordinates that have 6-7 digits to the left of the decimal place, the difference between US survey feet and "international" feet matters. For your eastings, 1.2 meters.
    – mkennedy
    Dec 3 '15 at 20:26
  • @mkennedy: that's a fair point, but not the root of my issue. My points are approximately 3500000m too far to the south and 70000m too far to the west Dec 3 '15 at 20:30
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ArcToolbox > Data Management Tools > Projections and Transformations > Feature > Project

  • Select feature of choice from layers list and drag to "Input Database or Feature Class" field in Project window

  • For "Output Coordinate System" field: Select > Projected Coordinate Systems > UTM > (projection of choice)

    • (MAKE SURE YOU SELECT THE PROPER ZONE!)

Then I had to open up the Attribute table for my new feature layer and change the x and y point coordinates to meters.

  • Right click columns > Calculate Geometry > (select meters)

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