Dear Even,

Sorry, I was using PROJ 8.2.1 as I didn’t expect the PROJ behaviour had changed 
since that version (see updated command results below).

We use the ETRF2000 realisation like most other NMAs, as this is recommended by 
EUREF for georeferencing, not ETRF2014! Therefore, ETRS89 should not be 
transformed to ETRF2014 with a null transformation. The correct transformation 
routes are:

  *   RD -> Amersfoort -> ETRF2000 -> ITRF2000 -> ITRF2014
  *   NAP -> ETRF2000 -> ITRF2000 -> ITRF2014

I expected this could be achieved by changing the Amersfoort-ETRS89 
transformation to Amersfoort-ETRF2000 “instead” in EPSG. I don’t understand 
what advantage a transformation to the ETRS89 datum ensemble “in addition” to a 
transformation to the specific ETRF2000 realisation in EPSG would give.

In PROJ 9.1.1. RDNAP to ITRF2014:
echo 128410.0957 445806.4960 -0.4754 2023.00 | cs2cs epsg:7415 epsg:7912 -d 9
Gives:
52.000004918 5.000008844 43.0018 2023.00
This should be:
52.000005512 5.000008256 43.0197 2023.00
Like RDNAP via ETRF2000 to ITRF2014:
echo 128410.0957 445806.4960 -0.4754 2023.00 | cs2cs epsg:7415 epsg:7931 -d 9 | 
cs2cs epsg:7931 epsg:7912 -d 9

In PROJ 9.1.1. RDNAP to WGS84:
echo 128410.0957 445806.4960 -0.4754 2023.00 | cs2cs epsg:7415 epsg:4326 -d 9
Gives:
51.999999889 5.000000153 -0.4754 2023.00
This should be:
52.000000000 5.000000000 43.0000 2023.00
Like RDNAP via ETRF2000 to WGS84:
echo 128410.0957 445806.4960 -0.4754 2023.00 | cs2cs epsg:7415 epsg:7931 -d 9 | 
cs2cs epsg:7931 epsg:4326 -d 9

Kind regards, Jochem





Disclaimer:
De inhoud van deze e-mail is vertrouwelijk en uitsluitend bestemd voor de 
geadresseerde(n).
Gebruik, openbaarmaking, vermenigvuldiging, verspreiding en/of verstrekking van 
deze informatie aan derden is niet toegestaan.
Op al onze producten en diensten zijn onze algemene leveringsvoorwaarden van 
toepassing
[https://www.kadaster.nl/algemene-leveringsvoorwaarden].

Disclaimer:
This email and any files transmitted with it are confidential and intended 
solely for the use of the individual or entity to whom they are addressed.
If you are not the intended recipient, you are notified that disclosing, 
copying, distributing or taking any action in reliance on the contents of this 
information is strictly prohibited.
Our general terms and conditions of delivery apply to all our products and 
services
[https://www.kadaster.com/general-terms-and-conditions].
_______________________________________________
PROJ mailing list
[email protected]
https://lists.osgeo.org/mailman/listinfo/proj

Reply via email to