[Qgis-user] Z-coordinates in CRS

[Greg Troxel]

Guy Meyvaert via QGIS-User <qgis-user at lists.osgeo.org> writes:

> Dear,
>
> We are struggling with the Z-coordinates.
> In Qgis we use Mergin Maps plugin with a self developed database.
> We connect the Mergin Maps App on our Phone or Tablet to a GPS-system (Emlid RX or RS3)

You're being very vague about what you are doing.  This makes it
unreasonable for anyone to try to help you, and it makes your post not
that useful for others.

You left out:

  - what geometry type are you using

  - (related) how are you storing height

  - how do you store the data and what does it look like when you get it
    back to gsis.  Include 'ogrinfo' output of a sample point and if all
    your data is protected by NDA go out and measure a geodetic control
    point in a public place.  (You should be doing that anyway to check
    your system.)

  - how are you dealing with ARP to mark offset
    + and also APC to ARP

  - are you doing differential GNSS and what is the datum of the
    reference system

> We have tried everything, also with a recalculation using
> python-scripts.

You did not describe everything in your email!

> We are a little bit desperate because our client needs the exact
> height (TAW) of the measured elements.

You probably need a consultant then!