Maybe you’d like something that looks more like it was chisled from stone, like this… ![]() Maybe you’d like to see actual shadows thrown by precipitous cliffs. They remind you a little too much of Google maps Terrain layer. You think the mountains look like they were extruded in plastic. (Although occasionally it is the pièce de résistance…)īut perhaps you don’t like the glossy, shiny quality of that hillshade above. Much of the time what we can get out of GIS software meets our needs for a hillshade, which, after all, is not the final map but a merely a layer of the map. This can do a lot to lighten up the darkest shadows, or to turn the hillshade into a ghostly wash that merely suggests relief without dominating everything else on the map. ![]() You can tweak the brightness and contrast in your GIS software, or stretch the histogram to your liking. ![]() (They do not, typically, however, calculate actual thrown shadows.) (60°, 337° and 1X, in this case.) They do some geometrical calculations to figure out the intensity of incident light on all the pieces of the landscape, and then produce a greyscale image. ![]() Hillshading algorithms typically take three parameters: the elevation of the sun, the azimuth (direction) of the sun, and the vertical exaggeration of the landscape. The hillshade by itself (left), and blended with hypsometric tinting (right) The shaded relief images (also often called a hillshade) that GIS software produces are pretty good.
0 Comments
Leave a Reply. |