TPE Web uses elevation data for calculations involving terrain and the relative heights of locations and subjects.
TPE Web provides several elevation data sources to choose from. These sources differ in their coverage, resolution, and the underlying data they use, so one source may provide better results than another in a particular location.
In this article, we’ll look at the elevation data sources available in TPE Web, how they differ, and what to consider when choosing between them.
Digital elevation models
TPE Web uses digital elevation models (DEMs) to obtain elevation data for locations around the world.
Different DEMs provide elevation data at different resolutions. Higher-resolution data can represent smaller terrain features in greater detail, while lower-resolution data provides a more generalized representation of the terrain. Some DEMs are single source, i.e. all the data they provide was collected using the same means. Other models are a synthesis of multiple underlying sources and so may vary in resolution and accuracy depending on the region you’re using. Generally, moderate latitudes and more populated areas enjoy higher resolution and higher accuracy coverage than extreme latitudes or remote areas.
TPE Web provides several elevation data sources, depending on your subscription plan. We’ll look at the available options below.
Elevation data sources in TPE Web
The elevation data sources available in TPE Web depend on your subscription plan.
| Data Source | Availability | Description |
|---|---|---|
| AWS Terrarium | Free, Supporter, PRO, and MAX | AWS Terrarium provides worldwide elevation data compiled from a number of public datasets. The underlying source and resolution vary by location, with higher-resolution regional data available in some areas. |
| Copernicus DEM (30 m) | PRO and MAX | Copernicus DEM provides worldwide elevation data at approximately 30-meter resolution. It is a digital surface model, which means that elevations may reflect features such as vegetation and buildings as well as the underlying terrain. |
| Mapbox Terrain-DEM | MAX | Mapbox Terrain-DEM provides worldwide elevation data compiled from multiple sources. The underlying source and resolution vary by location, allowing higher-resolution regional data to be incorporated where available. |
| Mapterhorn | MAX | Mapterhorn combines worldwide 30-meter elevation coverage with higher-resolution regional data where available. In many areas, it incorporates elevation data at resolutions of 10 meters, 5 meters, 1 meter, or better. |
| Google Elevation | PRO and MAX* | Google Elevation provides elevation data from Google’s elevation service. Unlike the other elevation sources, it is only available when you’re using one of the Google map types in TPE Web. |
*In accordance with licensing terms, Google Elevation is available only while a Google map is displayed.
Which elevation data source should I use?
For most purposes, the default elevation data source available with your subscription should provide suitable results. However, different sources may report different elevations for the same location, so it’s worth comparing them when accurate elevation data is important to your planning.
If you have a MAX subscription, Mapterhorn is a good default choice. It provides higher-resolution elevation data in many areas and will generally be the best place to start.
PRO subscribers can also compare AWS Terrarium with Copernicus DEM or Google Elevation. Google Elevation is available whenever you’re using a Google map.
Whichever source you choose, remember that elevation models have limitations. If precise elevation is important for a planned shot, consider comparing multiple sources and verifying the elevation independently.
The list of available elevation data sources depends on the latitude of the map pins and your subscription level.
Changing the elevation data source
To change the elevation data source, click the elevation displayed at the top of the map.
- Click the Elevation above Sea Level to change the data source
In the Elevation source dialog, select the data source you want to use. Sources that aren’t included with your current subscription are labeled PRO or MAX.
The elevation shown for the primary and secondary pins will update using the selected data source. If you’re using a Google map, you can also select Google Elevation.
Comparing elevation data sources: the Coonowrin example
No elevation data source will be the most accurate in every location. It pays to experiment and compare different sources when elevation accuracy is important.
A good example is Coonowrin in the Glass House Mountains, Queensland, Australia. As you might know, the Anglophone name for this peak is Crookneck – yes, that’s what our company is named after!
The official height of Coonowrin is 377 m. However, the elevation reported for the summit in TPE varies depending on the selected elevation data source.
In this example, Mapterhorn reports an elevation of +365 m, while AWS Terrarium reports only +264 m. Google Elevation reports +219 m for the same location – even less accurate.
The summit is a relatively thin ancient magma plug of a long-dormant volcano, making it the type of terrain feature that can be difficult to represent accurately in digital elevation data.
In this case, you cannot rely on the available elevation data sources for an accurate value. The safest advice is to survey the site yourself and measure the elevation angle using the Augmented Reality view in TPE for iOS or with a clinometer. Typically, you don’t need the actual elevation for photo planning purposes – just the elevation angle.
Sea-level Lock
Some data sources, such as AWS Terrarium, include not only terrestrial elevation but also bathymetry (water depth). Unfortunately, there’s no efficient mechanism to distinguish programmatically between land that lies below sea level and the bottom of a lake.
As a result, TPE offers a “ sea-level lock ” (see screenshot above), meaning that negative elevation values are clamped to a minimum of zero (+0m). For general purpose use, we recommend you leave this engaged to avoid negative elevations.
There are not very many areas of land that lie below sea level – you’ll likely be very well aware if you’re visiting one. In those cases, remember to disengage the sea level lock. Click the Elevation badge to adjust this setting, or if Geodetics is enabled, you can adjust it from the righthand panel.
