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I started creating a map in ArcMap by adding vector shapefiles. All of my vectors have data sources as:

Data Type:  Shapefile Feature Class 
Geometry Type:  Line

Projected Coordinate System:    NAD_1983_StatePlane_North_Carolina_FIPS_3200
Projection: Lambert_Conformal_Conic
False_Easting:  609601.22000000
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:    Meter

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

When I bring in a raster image downloaded from a North Carolina imagery earth-explorer database, the raster image looks a few hundred miles off from where it should be. The data source of the raster images is:

Spatial Reference: NAD_1983_2011_StatePlane_North_Carolina_FIPS_3200_Ft_US
Linear Unit: Foot_US (0.304801)
Angular Unit: Degree (0.01745329519943295)
Datum: D_NAD_1983_2011

When I add the raster, I get the Geographic Coordinate Systems Warning, saying that the data source of the raster ("GC_NAD_1983_2011") is different from the one used in the data frame. When I go in the Transformations options in the same dialogue box, and try to "Convert from GCS_NAD_1983_2011" to just "GCS_North_American_1983", there is no method available under the Using: dropdown, meaning I can't transform. What can I do to rectify this? How can I change the actual datum of the raster?

migrated from stackoverflow.com Jan 21 '16 at 15:08

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  • For future reference, Geographic Information Systems is generally a faster resource for getting application-specific questions like this answered more quickly. StackOverflow is more for programming questions (like if you want to write a python script to line up your data!) – Erica Jan 21 '16 at 3:02
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You can have two different projections that share the same datum. In this case, ArcMap can't really use a datum transformation because, well, there's nothing to transform -- they're both already NAD83.

Add the raster data into a new, empty map and use the ArcGIS Project tool (found in the Data Management / Projections and Transformations toolbox). You can put it into the exact same projection as your original data (NAD83 North Carolina State Plane, meters) and everything should line up correctly.

(Note: Don't use Define Projection unless your source data doesn't have ANY projection. It will overwrite a projection, not transform. See here for an Esri blog post about the difference.)

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