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assigning color breaks in color ramps to specific elevations

October 24 2009 | 0 comments
Categories: Symbology

Have a hillshade that combines both bathymetric and topographic data similar to your Crater Lake example. Unfortunately the Crater Lake color ramp does not quite fit the data I'm working with and I would like to break the color ramp between bathymetry blues and topographic greens at exactly sea level in the DEM. Is there a way to exactly define this break in the color ramp? I've attached screen shots of both the DEM and hillshade if it helps.


Mapping Center Answer:

The best way to deal with this is to create a separate DEM and hillshade for the area of the lake which you will then place OVER the DEM for the whole area. Then you can symbolize the lake rasters using a blue color ramp for the DEM and you will symbolize the DEM for the whole area using a hypsometric tint for elevation.

One other thing - I note that I am seeing something called "relief inversion" in the graphics you sent -- that is, the valleys appear to be hills and the hills appear to be valleys. This will happen when you do not illuminate for the west. You may want to re-create the hillshade to correct this problem.

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