Referencing your elevation data in an accurate measurement is just as important as collecting your elevation data with high accuracy equipment. Many GIS users prefer to use a geoid file that is accurate in their respective locations around the world.
Collector for ArcGIS, by default, will populate the altitude metadata field with a Height Above Ellipsoid (HAE) elevation value. The latest Trimble Mobile Manager app, currently only available on Android, will now allow you to select a geoid file to be used as the output GNSS reference frame that can then be consumed by Collector for ArcGIS to display Mean Sea Levels (MSL) elevation values. An attribute expression in the Collector pop-up can be used to view MSL values in real-time while in the field and a field calculation with arcade in ArcGIS Pro can be used to populate the MSL elevation value into an attribute field of the feature service.
This tech video will walk you through the steps of checking to see if your database or feature service is 3D enabled, configuring the Collector pop up with an attribute expression to view the real-time MSL elevation values, and how to populate the MSL elevation values into an attribute field of the feature service.
Note-There is a Collector Classic available in the respective app stores that doesn’t support the 3D geometry capturing and will only populate an elevation value in HAE into an attribute field. You can check out Alison Walker’s previous blog post on Mean Sea Level Elevation Data Using Esri’s Collector App on how to convert the HAE elevation data on a 2D feature service into an attribute field to MSL values.
For more information on Trimble Mobile Manager and Collector integration, check out these Trimble blog posts.
Orthometric Heights with Trimble GNSS and Esri Collector: Overview
Orthometric Heights with Trimble GNSS and Esri Collector: Configuration in the Office
Orthometric Heights with Trimble GNSS and Esri Collector: Configuration in the Field
Orthometric Heights with Trimble GNSS and Esri Collector: Collecting Data