Enhanced Raster Blending Techniques in ArcMap

Idea created by 1_ryan.clark on May 24, 2011
    Image processing tools like Photoshop, GIMP, or even some GIS Software like Global Mapper (http://www.globalmapper.com/) allows you to blend raster overlays in a variety of different ways. See http://emptyeasel.com/2008/10/31/explaining-blending-modes-in-photoshop-and-gimp-multiply-divide-overlay-screen/ for more information on these blending options.

    These types of blending can help to create much better cartographic products where the basemap is actually a combination of a few raster layers. Transparency (the only blending option that ArcGIS provides), generally produces a much less visually appealing image. 

    A good example of a situation where this is useful is for blending topographic basemap (from USGS Quadrangles) with a shaded relief map.