Vertical datum transformation error

[paulmartec]

Hello all.  I am aware this issue has been previously raised on an old thread which has advised me to create a new one.  I am now desperate to change the geoid on a large data set for a client.  I have posted on the old thread, have emailed Agisoft support, have messaged Alexeley personally and have received nothing.  Industry requires better service than this from Agisoft and issues like this where the software if not performing should not be left for a community driven forum to try and deal with.  Not good enough Agisoft and this experience does influence recommendations of the product over others who offer much superior customer service.  I am disappointed to say the least and now have an aggrieved client.

I am unable to set a custom geoid as the known error keeps populating.  I have followed the knowledge articles, changed the file name and downloaded the relevant .tiff to the appropriate folder.

So two questions for Agisoft,

1) How is this error corrected please
2) What is a reasonable timeframe to receive customer support?

Regards,

Paul

[Paulo]

Hello Paul,

I was able to create the following compound CS incorporating the AHD height as follows:

Code: [Select]

COMPD_CS["GDA2020 / MGA zone 54 + AHD height",
PROJCS["GDA2020 / MGA zone 54",
GEOGCS["GDA2020",
DATUM["Geocentric Datum of Australia 2020",
SPHEROID["GRS 1980",6378137,298.257222101,
AUTHORITY["EPSG","7019"]],
TOWGS84[0,0,0,0,0,0,0],
AUTHORITY["EPSG","1168"]],
PRIMEM["Greenwich",0,
AUTHORITY["EPSG","8901"]],
UNIT["degree",0.01745329251994328,
AUTHORITY["EPSG","9102"]],
AUTHORITY["EPSG","7844"]],
PROJECTION["Transverse_Mercator",
AUTHORITY["EPSG","9807"]],
PARAMETER["latitude_of_origin",0],
PARAMETER["central_meridian",141],
PARAMETER["scale_factor",0.9996],
PARAMETER["false_easting",500000],
PARAMETER["false_northing",10000000],
UNIT["metre",1,
AUTHORITY["EPSG","9001"]],
AUTHORITY["EPSG","7854"]],
VERT_CS["AHD height",
VERT_DATUM["Australian Height Datum",2005,
AUTHORITY["EPSG","5111"]],
UNIT["metre",1,
AUTHORITY["EPSG","9001"]],
AUTHORITY["EPSG","5711"]]]
then in Metashape I placed 1 point and converted between 'GDA2020 / MGA zone 54 + AHD height' and 'GDA2020 (EPSG::7844)' and got correct Geoid height correction as confirmed by looking at geoid AUSGeoid2020_20170908_win.tif file in Global mapper. Note that same tif file should appear in Datum Transformation Settings window under Geoid height entry. See attached screen copy....

Maybe you have problem with your tif file?

[paulmartec]

Thank you Paul.  I don’t have any coding experience and am looking to rely upon the method of creating a custom user set up.  I don’t understand how you have achieved your result I’m sorry.  The suggested workflow is simple in theory, select and download required geiod If available (which it is), download it and store in Agisoft geoid file on computer, load up as custom datum.  That’s what I’m after please.

[paulmartec]

Sorry, Paul.  I used the .tiff as per Agisoft download page.

[Paulo]

Yes Paul,

it seems that downloaded Tif from Geoid page refers to GDA94 datum instead of GDA2020... The following link https://drive.google.com/file/d/1CkqvROr2kSTf8ltsPXTeAsGTKGTfYblH/view?usp=sharing contains the AusGeoid2020 with correct reference datum... It should work...with attached prj file...

[paulmartec]

Thank you Paul, I see.  I’ll try that .tiff and report back.  Many thanks.

[paulmartec]

It looks like your Dropbox file is locked Paul.

[Paulo]

Paul,

I gave you access thru your Gmail a while ago ....

[paulmartec]

Oh ok, I’ll go in that way.  Many thanks.

[paulmartec]

That loaded up without an issue thanks Paul!