Vertical exaggeration and z-unit conversion of layers

There are two main reasons why you might need to use vertical exaggeration on feature layers.

The first is that geographic data is typically collected and represented in a coordinate system that has the same x,y units. However, when heights, depths, or elevations are recorded for features or surfaces, the z-units are not always the same as the x,y units of the coordinate system. For example, a set of well features might be stored in UTM meters but have a well depth attribute in feet. To represent the wells correctly in 3D, the z-values must be converted to UTM meters. Otherwise, when you extrude the wells in a 3D view, they will appear to be three times as deep as they really are.

The second reason is purely for representation. In areas with flat topography, for example, it may be advantageous to exaggerate the surface to highlight the subtle physical features that are there.

To convert the vertical units, or z-units, for feature layers, set the z-unit conversion layer property for the feature layer. Both ArcGlobe and ArcScene support this property.

To set a conversion factor for the height of a layer, do the following:

Steps:
  1. Right-click the layer in the table of contents and click Properties.
  2. Click the Elevation tab and go to the Elevation from features section to find the settings for Factor to convert layer elevation values to meters or a custom value.
  3. Click the Conversion Factor drop-down arrow and click one of the predefined types of conversion. You can select from:
    • feet to meters
    • custom
  4. If the standard conversion is used the value is displayed but not editable. You can type your own alternate value by selecting custom.
  5. Click OK.
TipTip:
  • The converstion factor option will not be enabled for 2D feature layers.
  • In ArcGlobe, only elevation and floating layers can have vertical exaggeration set. Draped layers will always be placed on the surface of the globe.

6/11/2012