Collect Orthometric Height in Field Maps and Projected Coordinate Systems in Field Maps

[BrandonWotachek]

Has anyone "cracked the code" on how to get the orthometric height attribute exported from a point feature collected in Field Maps?  I have read articles high and low on this subject but cannot figure out a successful way to get this to work.  I have seen some post and articles but the solutions are pages long.  This should be an easy out of the box solution/option. I am using an external GPS receiver and would like to record Z-values in NAVD1988(ft).  I see it records Altitude as ellipsoidal height, but I do not want that, nor can I think of why anyone recording Z-value would want that over orthometric height.  Additionally, I cannot get Field Maps to take a coordinate system other than WGS84, which I think would help me in recording orthometric height.  I can create another one in my profile within Field Maps, but in order to use the the esri "canned basemaps that you must have your project set-up to WGS84.  I have attempted to create my own simple basemap in my desired projection and bring that into Field Maps, but have had no luck, FieldMaps still says the map and profile coordinate system do not match.  Basemaps in ArcMap can be projected on the fly, why not in Field Maps?  For a new field collection app, Field Maps seems like it is not ready for "Prime Time".   I have other issues I could list, but I have found work arounds for those.   I would really like to use esri for a field collection app,  but may need to go to another companies app.  From a user who has been using Trimble TerraSync, Field Maps does not have near the functionality of TerraSync.  Granted TerraSync is now a software dinosaur, but has great functions and options for collection.

[ThomasHoman]

Hi Brandon,

Have you checked out the requirements for high accuracy FieldMaps  use? https://doc.arcgis.com/en/field-maps/ios/help/high-accuracy-data-collection.htm 

From what I am seeing, FieldMaps only uses the GPS ellipsoid height and has no knowledge of the geoid model concept, or the ability to apply it, to get to Orthometric height so must be handled in post collection processing and are very specific to the area you are working in. In the US the NGS handles is the caretake of the US data https://geodesy.noaa.gov/GEOID/ with others responsible for their respective jurisdictions.

TerraSync, being a Trimble product and an extension of their survey history, probably has full knowledge of the various geoid models out there and can apply them to field measurements. I still use Trimble TSC2's for field work and when setting up the job the geoid model to be used must be selected so I know exactly where you are coming from.

This would be a great idea and I would certainly upvote it!

Edit - It appears that there is already an idea in for this. https://community.esri.com/t5/arcgis-field-maps-ideas/measure-the-orthometric-height-in-field-maps/i... 

I hope this helps.

Respectfully,

Tom

[BrandonWotachek]

Tom,

Thanks for your input.  I had already reviewed the links you included above, including the work arounds.  I am not a fan of the work arounds when I know there is other software out there that can do what I need.  The fact that Field Maps does not understand Geoid and Orthometric Height is a big problem in my eyes.  If a field user has a high accuracy external GPS receiver, the option to collect accurate data should be an option in Field Maps and one should not have to post process ellipsoidal heights to get orthometric heights.  Not everyone is happy with "approximate".  I understand that one should not be collecting any sort of Z value with a phone or tablets internal GPS, but I feel esri should provide solutions for those of us that want to collect such data without using the full suite of a survey product such as Trimble Access.  I am not expecting an esri version of Trimble Access, but an app a little more robust would be nice.  I am hoping esri will improve Field Maps.  If anyone can recommend another Android app that works with a Juniper Geode GPS receiver and can work with projected coordinate systems and record orthometric height, please let me know.

[ColinLawrence]

Hi @BrandonWotachek ,

Support for vertical transformations within the app is on the Field Map's team road map; the underlying runtime must support this before it can be brought in. As you might imagine this is a complicated task to build into a mobile app.

There are methods to view the ortho heights within the popup (attributes) of a feature but does require post processing to bring this into the feature geometry. It sounds like you are aware of these tools. Direct support within the app in the future will certainly simplify this workflow. 

Regards,

Colin

[DanielleRose]

Hello Colin,

Do you happen to know time frame? We need orthometric height and vertical accuracy reported for our project so trying to figure out the best route for us going forward. Not sure if we should postpone or find an alternate software.

[ColinLawrence]

Its on the near to mid-term scale in terms of our roadmap. This is still a little murky due to the underlying dependencies. I apologize I cannot give a more specific time at this point. 

Regards,

Colin

[JMGhosh]

Hey @ColinLawrence , 

Has this functionality been added to Field Maps? I'm still having an issue with not seeing the Ortho height in Field Maps. If it hasn't been added yet, is there a timeline as to when we might see this added? 

Thanks, 

James

[DannySmith12]

Hi @JMGhosh ,

Wanted to add to the discussion. In Field Maps, one needs to create a calculated arcade expression, assure it is showing in the pop-up table (it will not by default), have GPS Metadata fields added (ArcGIS Pro tool) and Z enabled on the web layer. After creating an extra blank field called Ortho height for example with double numeric format, create the calculated arcade expression in a web map and also in Field Maps. The script is at the bottom. I have not tested this as I am running in ArcGIS Enterprise 10.9.1 and calculated arcade expressions aren't available in this version. It is available in 11.0 but we are not venturing there yet. Let me know if this works. 

// change to false if feet desired
var useMeters = true;

var geom = Geometry($feature);

if(!IsEmpty(geom)){
  var elevation = geom.Z;
  if(useMeters){
      return elevation;
  }
  else {
    return Round(elevation * 3.2808,3);
  }
}
else {
  return null;
}

[JMGhosh]

Hi @DannySmith12 

Thanks for the reply. This is actually a workaround I currently use. But I was hoping that ESRI would implement a more straightforward approach to where this becomes part of the metadata fields and populated automatically as data collection is taking place. 

Thanks again!

James

[DannySmith12]

@JMGhosh Yeah that would be ideal! Quick question regarding your workflow. Did you ever have issues with the new ortho height data populating in field maps pop-up, but not in the web map?