How to use vertical coordinate systems and geoids in Pix4Dmatic – Support

This article explains how to select the correct vertical coordinate reference system, geoid, or geoid height in Pix4Dmatic.

What is a geoid model: The geoid is defined based on the earth's gravity field and is used as the reference surface for heights. Beneath the continents, it can be considered as a continuation of the mean sea level surface.
For more information, see the Orthographic (geoid) vs. ellipsoidal heights article.

Pix4Dmatic supports global geoids (EGM84, EGM96, and EGM2008) and local geoids, for example, GEOID12B in the US and OSGM15 in the UK.

For local geoids that are not included in the Pix4Dmatic database, it is possible to specify the Geoid height value to convert between ellipsoidal and orthometric heights.

Video tutorial: How to use vertical coordinate systems and geoids in Pix4Dmatic

IN THIS ARTICLE

Selecting the vertical coordinate reference system
Selecting the geoid
Selecting the geoid height
List of supported geoids

Access: For more information on how to define the horizontal and vertical coordinate systems for images, GCPs, and outputs, see How to use coordinate systems in Pix4Dmatic article.

Selecting the vertical coordinate reference system

After selecting the Horizontal coordinate reference system, the list of Vertical coordinate reference systems is available.

Only Vertical coordinate reference systems within the area of use of the Horizontal coordinate reference system are listed.

Example: For GCPs in:

Horizontal coordinate reference system: NAD83 - EPSG:4269.
Vertical coordinate reference system: Ellipsoidal height.

Pix4Dmatic vertical coordinate system ellipsoid

Settings in Pix4Dmatic for GCPs in NAD83 - EPSG:4269 with ellipsoidal heights.

Selecting the geoid

Several geoid models are available in the Pix4Dmatic database. The full list is available in the List of supported geoids section.

The list of available geoids depends on the selected vertical coordinate reference frame.

Important: Before selecting the Geoid, it is necessary to select the correct Vertical coordinate reference system. Only geoids corresponding to a certain vertical coordinate reference system are listed in the Geoid drop-down menu.

Example: For GCPs in:

Horizontal coordinate reference system: NAD83 - EPSG:4269.
Vertical coordinate reference system: NAVD88 height - EPSG:5703.
Geoid: GEOID12B.

Settings in Pix4Dmatic for GCPs in NAD83 - EPSG:4269, NAVD88 height - EPSG:5703, and GEOID12B.

Selecting the geoid height

At the moment, the import of local geoids is not possible. As a workaround, it is possible to specify the Geoid height value, which represents the height between the base ellipsoid of the horizontal coordinate reference system and the desired geoid.

The Geoid height value is used to convert the image geolocation (WGS 84 ellipsoid or EGM96 geoid) into the desired project coordinate system.

Note: When relying only on the image geolocation (GCPs not used), using Geoid height is recommended for small areas where geoid and ellipsoid can be considered parallel in a small portion of terrain. This approach will introduce inaccuracies if the project area is large if there are significant variations between the ellipsoid and geoid.

When GCPs are used, the project is fitted to the position of GCPs, and the inaccuracies introduced by a single Geoid height value do not affect the reconstruction of the project.

Example: For GCPs in:

Horizontal coordinate reference system: CH1903+ / LV95 - EPSG:2056 (base ellipsoid Bessel 1841 - EPSG:7004).
Vertical coordinate reference system: LHN95 height - EPSG:5729.
Geoid: CHGeo2004 (not available).

In Switzerland, the National height network LHN95 is based on the CHGeo2004 geoid but is not available in Pix4Dmatic. Since the base ellipsoid for the horizontal coordinate system (CH1903+ / LV95 - EPSG:2056) is ellipsoid Bessel 1841 - EPSG:7004, the difference between the ellipsoid Bessel 1841 and CHGeo2004 geoid should be specified as the Geoid height value.

Pix4Dmatic vertical coordinate system geoid_height

Settings in Pix4Dmatic for GCPs in CH1903+ / LV95 - EPSG:2056, LHN95 height - EPSG:5729 and CHGeo2004 geoid.

List of supported geoids

Country or region	Vertical coordinate reference system	geoid	Note
Global	EGM96 height - EPSG:5773	EGM96	15' geoid
Global	EGM2008 height - EPSG:3855 MSL height - EPSG:5714	EGM2008	2.5' geoid
Austria	EVRF2000 Austria height - EPSG:9274	Austrian Geoid 2008
Australia	AHD height - EPSG:5711 AHD (Tasmania) height - EPSG:5712	AUSGeoid98
	AHD height - EPSG:5711 AHD (Tasmania) height - EPSG:5712	AUSGeoid09
	AHD height - EPSG:5711	AUSGeoid2020
Canada	CGVD28 height - EPSG:5713	CGG2000/HTv2.0
	CGVD2013(CGG2013) height - EPSG:6647	CGVD2013
	CGVD2013(CGG2013a) height - EPSG:9245	CGVD2013a
Denmark	DVR90 height - EPSG:5799	DVR90
Denmark	DNN height - EPSG:5733	DNN
Greenland	GVR2000 height - EPSG:8266	GVR2000
Greenland	GVR2016 height - EPSG:8267	GGEOID16
Faroe Islands	FVR09 height - EPSG:5317	FVR90
France	NGF-IGN69 height - EPSG:5720	RAF09
France	NGF-IGN69 height - EPSG:5720	RAF18
Corsica	NGF-IGN78 height - EPSG:5721	RAC09
Iceland	ISH2004 height - EPSG:8089	IceGeoid2011
Japan	JGD2011 height - EPSG:6695	GSIGEO2011 v2.1
Netherlands	NAP height - EPSG:5709	NLGEO2018
New Zealand	NZVD2009 height - EPSG:4440	NZGeoid2009
New Zealand	NZVD2016 height - EPSG:7839	NzGeoid2016
Slovakia	Baltic 1957 height - EPSG:8357	DVRM05	Only available to Baltic 1957 height
Spain	Alicante height - EPSG:5782	EGM08-REDNAP
Sweden	RH2000 height - EPSG:5613	SWEN17
UK	Belfast height - EPSG:5732 Douglas height - EPSG:5750 Lerwick height - EPSG:5742 Malin Head height - EPSG:5731 ODN (Offshore) height - EPSG:7707 ODN height - EPSG:5701 ODN Orkney height - EPSG:5740 St. Marys height - EPSG:5749 Stornoway height - EPSG:5746	OSGM15	Including Great Britain, Ireland, and North Ireland
US	NAVD88 height - EPSG:5703 NAVD88 height (ft) - EPSG:8228 NAVD88 height (ftUS) - EPSG:6360	GEOID99
	NAVD88 height - EPSG:5703 NAVD88 height (ft) - EPSG:8228 NAVD88 height (ftUS) - EPSG:6360	GEOID03
	NAVD88 height - EPSG:5703 NAVD88 height (ft) - EPSG:8228 NAVD88 height (ftUS) - EPSG:6360	GEOID09
	NAVD88 height - EPSG:5703 NAVD88 height (ft) - EPSG:8228 NAVD88 height (ftUS) - EPSG:6360 NMVD03 height - EPSG:6640 PRVD02 height - EPSG:6641 VIVD09 height - EPSG:6642 ASVD02 height - EPSG:6643 GUVD04 height - EPSG:6644	GEOID12A
	NAVD88 height - EPSG:5703 NAVD88 height (ft) - EPSG:8228 NAVD88 height (ftUS) - EPSG:6360 NMVD03 height - EPSG:6640 PRVD02 height - EPSG:6641 VIVD09 height - EPSG:6642 ASVD02 height - EPSG:6643 GUVD04 height - EPSG:6644	GEOID12B
	NAVD88 height - EPSG:5703 NAVD88 height (ft) - EPSG:8228 NAVD88 height (ftUS) - EPSG:6360 PRVD02 height - EPSG:6641 VIVD09 height - EPSG:6642	GEOID18

Selecting the vertical coordinate reference system

Selecting the geoid

Selecting the geoid height

List of supported geoids

Related articles

Article feedback (for troubleshooting, post here)