One of CalTopo’s core features has always been the ability to blend multiple map layers together. Until now, that’s been done by creating a layer stack and varying the opacity of each layer to suit. This works, but shaded relief has always been a weak point. In order to keep the relief layer from washing out the rest of the map, I had to crank up the exaggeration. This meant you could use less relief and get less washout, but it reduced the layer’s ability to capture small details.
Professional mapmakers solve this problem by using more advanced techniques than opacity based layer stacking. One of those is to do a multiply blend, where each pixel on the map is multiplied by the intensity of the hillshade, on a 0-1 scale. This darkens the image a bit, but does a much better job of preserving it. The photo below is the same image of Shasta with multiply blend relief shading . . .