The Elevation Layer allows you to view the elevation of your map by use of either our digital surface model (DSM) or our digital terrain model (DTM). Most users will use our digital surface model which is the default and will display heights of all objects within the map. Additional tools within the layer will allow you to explore your data even more deeply through a perspective of the elevation and depth of each area of the map.
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Getting the Elevation Layer
The elevation data on your map is taken from geospatial information embedded in your images and automatically generated when you process your imagery into a map. By default, the elevation information is expressed in the WGS 84 Global Reference system.
Using the Elevation Layer
By using the Elevation layer and toolbox, you can adjust the contrast to highlight variability within your map.
To get started, make sure you have selected the Map Analysis section, and select the Elevation layer from the side panel at the left. You will see the digital surface model (DSM) projecting the height of your map.
When you open your map from the dashboard, it will automatically be brought to the orthomosaic map. Choose Elevation layer from the options underneath the "Map" tab.
This will also update the panel in the top left showing a histogram of the elevations of the data, and the data itself. By clicking on the arrow next to the Elevation Layer you can expand your elevation Toolbox.
Expand your elevation options by clicking on the arrow next to the Elevation layer.
Intensity
You can also select different intensities of the shadows, from Low to Max, to emphasize depth:
Adjust Opacity:
Range of Values
The elevation histogram has a few different values. Using the bottom sliding bar, you can change the values presented on the map. The map will automatically update.
Adjust the range of the elevation presented using the handles at the bottom of the histogram.
The top row of numbers is the area of the total map that falls within the range specified using the scale bar at the bottom. The number at the top of the histogram presents the area of the map that falls within the range specified by handles at the bottom.
Important notice for maps processed before April 18, 2019
Prior to April 18, 2019, DroneDeploy used relative elevation data when processing maps, rather than the absolute elevation. This means that for older maps processed before this date, elevations are not expressed relative to WGS 84 global elevation but rather expressed as feet or meters above or below the takeoff point of the drone. If you would like to adjust the elevations of these older maps to match those of newer maps, you can do so by using the Elevation Calibration tool.
Elevation Profile
Using the Distance tool within the Annotation & Measurement Toolbox, you can display the cross-section or elevation profile of your map.
The elevation profile is useful to:
- Measure the height of certain features
- Measure the slope of the line segment (height change / distance)
- See if an area is flat/bumpy/sloped
- See the elevation at a given cursor point
Steps to display the elevation profile:
- Create a line using the distance tool.
- Click on the line so you see the cross arrows.
- View the elevation profile in the map panel at the left.
The vertical height and cross-section under the line are also included in the Elevation Profile which is useful for a full view of the elevation layout of your site.
Elevation at Cursor Point
The elevation of a specific point on your map is shown at the bottom left corner of the map itself. Simply space your cursor over any point on the map and you will see the elevation of that point.
Exporting the Elevation Map
After making sure you have the appropriate limits set in the histogram, you can export the elevation data by selecting the Elevation Layer within the Export tool.
You will see several formats to choose from, including Contours and Raw Elevation Values (DEM), if you are in the Individual or Enterprise subscriptions.
Click on Export, select the Elevation Layer and choose the right file format that you want to export.
It is important to note that the DEM export will be based on the elevation profile set in DroneDeploy.
Learn more about the different file formats available for export in our guide Data Export Formats.
Viewing, Exporting and Measuring Against Terrain (DTMs)
The elevation data captured by a drone includes all surfaces it sees, including trees, equipment and other structures. This elevation is called the Digital Surface Model and is available to all users that are able to view the elevation layer.
However, if customers want to remove these obstructions so that they can understand the terrain beneath when designing a project, estimating the earthmoving required, or measuring volumes of materials on site, they can now do this within the dashboard by using the Digital Terrain Model (DTM) for elevation.
A comparison of the elevation of the Digital Surface Model which takes into account buildings, trees and equipment vs. our Digital Terrain Model which allows viewers to view the elevation omitting these objects.
Example of how a conveyor is not displayed within the Digital Terrain Model.
Viewing the DTM Layer
To view the DTM layer instead of the default DSM, turn on the elevation layer and then toggle on “Terrain only”. You can also change the opacity of the layer by drilling down to the Elevation page.
Using DTMs as Volume Measurements
In the majority of cases, customers should use the regular DSM elevation to make volume measurements. However, some customers may want to measure the volumes of stockpiles and exclude conveyors and equipment that are on top of the piles.
For mining customers, we use a special DTM algorithm designed to preserve the stockpile in the DTM but remove conveyors and other equipment. These customers should select “Digital Terrain Model” as the surface when making volume measurements so that they can exclude conveyors and other equipment.
By changing the surface from the Digital Surface Model to the Digital Terrain Model a user is able to exclude a conveyor from his measurement.
Exporting the DTM in App
You can now export the DTM layer in the DroneDeploy dashboard like any other export. To export the DTM layer, simply click the Export button at the bottom of the explore page. If the DTM layer is already turned on, it will be selected by default, but if not, you will be able to select it from the dropdown if it’s available. DTMs can be exported in the following formats: JPG, PDF, Geotiff, raw values, DXF, SHP.
