I am using a Trimble R2 with a VRS subscription to achieve cm horizontal accuracy and would like the ability to apply a geoid to achieve realtime elevations.
I had the same question Joey as our shop is Collector-tracked. Our solution (for now) has been a geoprocessing script running in the background against current Geoid data (spatial join + uniqueid-join + field calcs basically) . I found this thread helpful for importing the Geoid data into an ESRI format (Import NGS Geoid Model to ArcGIS GRID). Our current process isn't instantaneous and we're considering different time intervals (cost/benefit), but after testing against NGS monuments we decided to run with it for the time being.
Also, currently we have ProjectZ tool as a workaround if you want to have new point features with orthometric height. You will collect point feature with GNSS metadata, including Altitude (ellipsoid height). Then you covert it into point feature with Z value at the orthometric height using ProjectcZ tool. The tool leverages vertical datum transformation capabilities in ArcMap and ArcGIS Pro: collector-tools/CollectorUtils at master · Esri/collector-tools · GitHub
This is not realtime but it can work for some user cases.
I recently collected x,y, and altitude values in the Collector app using the GNSS metadata fields. I would like to use the ProjectZ tool to convert my altitudes into orthometric height, but I am not sure what to enter for the input coordinate system for x and y and the input coordinate system for z. Are these 3 GNSS metadata fields in WGS 1984?
The X, Y, Z values in the GNSS metadata fields are raw data from your GNSS receiver. You will use whatever coordinate system your receiver or correction service uses to collect this data. For example, if you use a NAD83 2011 base station, the "Input Coordinate System" would be NAD 1983 2011. I hope this helps!
