You do not need to do anything special to import a georeferenced image file into Surfer. Click Home | New Map | Base, select the TIF file and click Open. If the image is georeferenced and the georeferencing file is in the same directory as the image file, it will import in the correct map coordinates.
To export a GeoTIF with the a TFW world file from Surfer, you can:
- Click File | Export.
- Change the Save as type to TIF Tagged Image, give your file a name, and click Save.
- In the Export Options dialog, on the Spatial References page,
- Choose the Map corresponding to your desired output coordinate system from the Coordinate System list.
- Check the check box next to ESRI World File.
- Click OK and the TIF and TFW files are exported.
Updated October 4, 2018