SAGA Relief Shading

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    Method

    Relief shading gives a DEM a more "3D" look. To use relief shading in SAGA, follow the steps outlined below:

  1. Ensure that you have your DEM open in SAGA. Create a Map view of the DEM by double clicking on it in the 'Data tab. Without the relief shading the DEM looks like the image below.

  2. SAGA relief shading1.png


  3. In the Modules tab of the workspace section, expand the "Terrain Analysis - Lighting, Visibility" option and select "Analytical Hillshading".

  4. Frame


  5. In the options section, select the Grid System that the DEM belongs to (check this in the Data tab of the workspace). In the Elevation option select the DEM.<br< The other options can be left at the defaults, but can be changed if desired.

  6. SAGA relief shading3.png


  7. Select the Execute option.
  8. After a few seconds (or minutes depending on the size of the grid), a tone should sound and the process is complete.
  9. In the Data tab, a new grid should appear called Analytical Hillshading'.

  10. SAGA relief shading4.png


  11. Add this layer to the Map containing the DEM, this can be done by double clicking on the Analytical Hillshading dataset in the Data tab, and then selecting the map containing your DEM.

  12. SAGA relief shading5.png


  13. In the Map window, the Hillshading grid should display on top of the DEM

  14. SAGA relief shading6.png


  15. In order to see the original DEM, select the Analytical Hillshading Grid in the Data tab, and then set a transparency in the Settings tab. Hit apply.

  16. SAGA relief shading7.png


    The DEM should now appear as a relief shaded DEM.

    SAGA relief shading8.png


  17. The "Analytical Hillshading" grid can be saved as a separate layer for future use. To do this, select the Analytical Hillshading grid in the data tab, right-click on this grid and select Save-As. Give the grid a sensible name, for example the original DEM name and "_relief", in the example above the relief shading grid for "DEM_M01" was saved as "DEM_M01_relief".