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exporting a color hillshade or DRG semi-transparent over hillshade

December 03 2011 | 1 comment
Categories: Map Data

Hello,

Back in the commandline ArcInfo days there was a GRIDCOMPOSITE command that allowed you to combine two rasters and maintain any transparency settings. With this you could create a color hillshaded raster datasets or custom 3D topomaps.

It is easy enough to bring a dem and hillshade into ArcMap and make the hillshade semi-transparent within the ArcMap document.

You can then export the data view as a GeoTiff with world file. However, that limits you to the visible extent of your dataview.

You can also export a layout and then georeference the result.

However, these are clunky solutions. How can I combine two rasters into one maintaining color and symbology settings like I could in ArcInfo 7?.

I want to create a custom 3D topo raster dataset with the topo layer laid semi-transparently over a hillshade. I'd also like to be able to create custom color hillshade images as a single file.

Thanks.

Mapping Center Answer:

The way to do this in the past would have been the color model conversion functions in Spatial Analyst's map algebra, but those did were not included in ArcGIS version 10.

So, the solution if you are using 9.3 is to use the Single Output Map Algebra tool or include SOMA in a model and that should work for you. Here is a link to the 9.3 online help topic for An overview of the Color Model tools.

Or there is a python script that a user has written to do this - you can use that in 10: http://forums.arcgis.com/threads/17459-.

Additional clarification needed posted by Kurt Menke on Dec 6 2011 11:19AM
So this tool lets one convert an RGB raster to HSV but that would still just leave me with two rasters right? How would I combine two rasters at that point to get a color hillshade raster or a 3d topographic map?

Would the use of Mosaic Datasets work? I really know nothing about them.

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