Custom geographic transformations are performed in ArcGIS Desktop to transform map data from one geographic coordinate system (GCS) or datum to another. If the map you intend to publish includes a custom geographic transformation, you should ensure that any files needed by the transformation are accessible to ArcGIS Server.
Follow these steps when publishing a map with a custom transformation:
- Run the Create Custom Geographic Transformation geoprocessing tool in ArcMap or in ArcGIS Pro. The output of this tool is a .gtf file saved in the ESRI\<ArcGIS product>\ArcToolbox\CustomTransformations folder in your user profile's Application Data folder. This folder is created by the tool if it doesn't exist. If the Application Data folder is read-only or hidden, the output is created in ArcToolbox\CustomTransformations under the user's temp folder.
- If your transformation needs any supporting files, such as a Grid Shift Binary (.gsb) file, copy them into the pedata folder in your ArcGIS Desktop install drive. Alternately, if you have installed the ArcGIS Coordinate Systems Data component, copy your files into the CoordinateSystemsData > pedata folder. In either case, browse to the subfolder of pedata, named for the method you used to create the custom transformation (for example, ntv2) and paste your copied files there.
- If you copied any supporting files to the Desktop pedata folder in step 2, copy them again into the pedata folder in the ArcGIS Server installation directory. As before, find the folder within pedata corresponding to your transformation method and paste the files there.
- When preparing a map for publication, make sure the custom transformation is in use within the map. If the map contains layers that use both the input and output geographic coordinate systems from the custom transformation, make sure the transformation is active:
If you do not plan to have layers that use your custom transformation's input and output GCS in the same map, add a layer that uses the GCS that will not be in the final map, set the custom transformation, then remove the layer. The transformation will then be stored with the map.
- In ArcMap, right-click on your Data Frame in the Table of Contents panel, then open its Properties. Select the Coordinate System tab, then click the Transformations button. Verify your custom transformation is selected.
- In ArcGIS Pro, right-click on your Map in the Contents panel, open its Properties, then click Transformation. Verify your custom transformation is selected.
- When your map is ready, publish it. If you're using ArcMap, you can publish a map service to ArcGIS Server; if you're using ArcGIS Pro, you can share a web map to an ArcGIS Enterprise portal, powered by a map service published to a federated ArcGIS Server site. The specifications of your custom transformation will be stored with the map service.
Your map service or web map will include the custom geographic transformation applied to your GIS data. This includes real-time processing as you zoom and pan the map.