DEM Grayscale Visualization

//DEM grayscale
//VERSION=3
return colorBlend(DEM, [-12000,-9000,-5000,-1000,-500,-200,-50,-20,-10,0,10,30,50,200,300,400,500,1000,3000,5000,7000,9000], [
[0.000, 0.000, 0.000],
[0.098, 0.098, 0.098],
[0.216, 0.216, 0.216],
[0.243, 0.243, 0.243],
[0.275, 0.275, 0.275],
[0.294, 0.294, 0.294],
[0.314, 0.314, 0.314],
[0.333, 0.333, 0.333],
[0.353, 0.353, 0.353],
[0.392, 0.392, 0.392],
[0.431, 0.431, 0.431],
[0.510, 0.510, 0.510],
[0.549, 0.549, 0.549],
[0.627, 0.627, 0.627],
[0.706, 0.706, 0.706],
[0.784, 0.784, 0.784],
[0.843, 0.843, 0.843],
[0.882, 0.882, 0.882],
[0.922, 0.922, 0.922],
[0.961, 0.961, 0.961],
[0.980, 0.980, 0.980],
[1.000, 1.000, 1.000]])