Measure the orthometric height in Field Maps

05-18-2021 04:47 AM
New Contributor II

What the Field-Maps App is doing:

Right now our measurement crews connect their GNSS-antenna to their iPad (iPad Pro 11”, 2nd generation running iOs 14.3) and add points to our web-feature-layer. The height, which the app is saving is known as “Height Above Ellipsoid”. Germany (and other European countries) use another height called the “Normalhöhennull” (orthometric height). The Field-Maps app can display the “Normalhöhennull” but it will only save the (for us useless) “HAE”.

What is the problem:

If we want to measure the height of the GNSS-antenna, we always need to open the app of the antenna manufacturer, copy the (orthometric) height, and then we paste it into a field of the feature layer we specifically created for this purpose. This adds human error to the process, which is unfortunate. Another workaround would be post processing the data, but that would need a person who does that, and would probably add calculation error, so we would like to have it shown correctly in the first place.

How this will help us:

In the past few months we’ve invested in a lot of hardware (e.g. GNSS-Antennas, iPads, etc.) with the goal to simplify the process of our measurements, but with the wrong height it is more of an obstacle than a relief to use it. At the moment the data that the measuring crews are gathering, needs to be fixed by an ArcGIS Pro operator before it can be further processed and analysed by our CAD or laboratory staff. This adds big delays to our workflow.

Why this is important:

We as a German authority must work with our official German standards especially when we are measuring things. The “Normalhöhennull” is the standard for every German authority, office, department and university. I would say, that every time someone is measuring the height somewhere in Germany, it will most certainly need to be the “Normalhöhennull” because it is the national standard since 1992. Because of that not only our authority has this problem, but everyone who wants to measure the height in Germany using Field Maps.


Same problem for us in the Netherlands. We use NAP (New Amserdams Peil) here. This is comparable to "Normalhöhennull" in Germany. Now we are actually forced to work with other software to make accurate height measurements and working with an accurate GNSS antenna in combination with Field Maps has no added value for us.


Here is a list of people having the same struggle and their workarounds.

Is it possible to collect accurate Z coordinate va... - Esri Community

Orthometric Heights (MSL) and GNSS Configuration o... - Esri Community

Solved: Cordinate systems and transformations with collect... - Esri Community

I really think there should not be the need for a workaround, because the GNSS antennas already pass the orthometric height to the Field Maps / Collector App

Status changed to: In Product Plan

@DougMorgenthaler I see this was changed to in product plan, have there been any updates on this? I am trying to use an EOS Arrow Gold receiver to collect orthometric heights. Field Maps is reading the ortho height in the GPS receiver monitor but not recording them to the attribute tables. Seems pretty weird that it would be able to read it and interpret it but not record it?


@data_dog EOS has a work around for getting those ortho values saved as the z-geometry value.

Eos Tools Pro: How to Configure Orthometric Heights - Eos (

ArcGIS Collector (v18.1.0): How to Record Survey-Grade Orthometric Heights - Eos (


But yes, I wish would do more to get this built in. Note that the arcade expression for the display of z geometry wasn't working in the web viewers, but worked fine in field apps.


Bad Elf and it's Flex unit does this too now, if your looking at cheaper alternatives to the EOS Arrow Gold.



@KyleLandonthe EOS is through a university, I'm doing research so I just need it to work for now. I had been following both of those tutorials already actually two days ago when I started this process and got to the point of the arcade expression where it is glitched and does not work and will not let you save it. At this point I'm already configuring a QGIS server to just do it homebrew and skip all the AGOL stuff.