Looking for Elevations in US Survey Feet

I have looked around the forum and docs and cant seem to find any info on the topic. My lat and long are great…but I can’t figure out the elevations. Example, my base station in Tampa, FL (a FDOT NTRIP) is locked in and elevation says -12.xxxm and my rover says -3.xxxm

WHAT THE HECK am I doing wrong here? Or how do I get it to read US Survey Feet?

Reachview outputs is looking for height above ellipsoid. Your NTRIP service is outputting from thir website
What is the established datum for FPRN?

Before August 2, 2014:
NAD(83)-(CORS96)-(Epoch 2002.0000).

After August 2, 2014:
NAD(83)-(2011)-(Epoch 2010.0000).

The FDOT maintains and publishes universal coordinates (geocentric polar and Cartesian) for the Florida Permanent Reference Network (FPRN) as we must deal with one coordinate system for the entire state. We leave it up to the end user to translate our universal coordinates into whichever State Plane (SP), Universal Transverse Mercator (UTM), or other projection that is appropriate for his or her use. Today, virtually all vendor-supplied GPS processor packages come with projection translators that can be tailored to one’s particular needs. The National Geodetic Survey (NGS) also makes available translators at their web site for producing state plane coordinates from geocentric coordinates such as those published for the FPRN.

The old and new FPRN geocentric coordinates are based on the same ellipsoid which is GRS1980. This is the ellipsoid on which all North America Datum of 1983 (NAD83) coordinates are based. Therefore you can use the same projection translator for the old and new FPRN universal coordinates for your comparison at specific locations. The FDOT does not have the resources to provide specific projection comparisons for specific sites as each site (be it FPRN station or other control) can have multiple projection coordinates associated with it. We leave that exercise of producing projected plane coordinates up to the end user.

You need another app to display survey ft in realtime (Mobile Topo Pro among others)


I am looking for mobile topo app as you suggested and I can not find one. Do you have a link to one?

Mobile topographer pro in app store

I will keep looking but I typed in exactly what you wrote and only two apps pop up and neither are it.

ahh…not on ipad. I found it for Android

Checkout Mapit GIS (pro also).

But why is this? Emlid rover has 9m higher difference?

Because the BASE is set at a fixed -12.xxxm below the ellipsoid… and his particular location of measurement is -3.xxxm below the ellipsoid?

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