rbanick · January 22, 2018 22:23
diff --git a/Creating Hillshades in QGIS b/Creating Hillshades in QGIS
 QGIS Hillshades are not hard, but they're often a little screwy. That's because units of measurement for elevation and x/y are often different. So, for instance, your DEM may be projected in WGS84 and hence have decimal degree units. But the DEM elevation units are often in meters. You need to account for this in the "scale" setting of QGIS.

 The basic rule of thumb is this:

 If everything is in meters, use scale factor 1.0 (default).
 If x/y is in degree and z in meters, use scale factor 111120.
 If x/y degree and z is feet, use scale factor 370400.

 So, in QGIS 2.6, go to Raster --> Analysis --> DEM (Terrain Modules)
 Load up your data, name the new file, and leave all the settings the same EXCEPT for scale. In most cases (SRTM data) you'll then rename scale to 111120.


 *Please note* that 111120 is for equatorial countries. It works fine for near equatorial countries as well. For countries farther away you'll have to recalculate the value yourself. You can find the relevant equations in the first answer here: http://gis.stackexchange.com/questions/95337/scale-and-z-factor-have-no-effect-on-hillshade-analysis-in-qgis

 More info:
 http://anitagraser.com/2012/01/19/a-guide-to-beautiful-reliefs-in-qgis/
 http://niketnarang.wordpress.com/2012/06/11/creating-a-hill-shade-from-dem-using-qgis/
	QGIS Hillshades are not hard, but they're often a little screwy. That's because units of measurement for elevation and x/y are often different. So, for instance, your DEM may be projected in WGS84 and hence have decimal degree units. But the DEM elevation units are often in meters. You need to account for this in the "scale" setting of QGIS.

	The basic rule of thumb is this:

	If everything is in meters, use scale factor 1.0 (default).
	If x/y is in degree and z in meters, use scale factor 111120.
	If x/y degree and z is feet, use scale factor 370400.

	So, in QGIS 2.6, go to Raster --> Analysis --> DEM (Terrain Modules)
	Load up your data, name the new file, and leave all the settings the same EXCEPT for scale. In most cases (SRTM data) you'll then rename scale to 111120.


	Please note that 111120 is for equatorial countries. It works fine for near equatorial countries as well. For countries farther away you'll have to recalculate the value yourself. You can find the relevant equations in the first answer here: http://gis.stackexchange.com/questions/95337/scale-and-z-factor-have-no-effect-on-hillshade-analysis-in-qgis

	More info:
	http://anitagraser.com/2012/01/19/a-guide-to-beautiful-reliefs-in-qgis/
	http://niketnarang.wordpress.com/2012/06/11/creating-a-hill-shade-from-dem-using-qgis/