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<p class="MsoNormal"><span lang="EN-GB" style="font-size:11.0pt;font-family:"Arial",sans-serif">Some transformations that used to give correct results (e.g. in PROJ 9.7.1) do no longer give results according to the official transformation (Amersfoort to ETRS89
(9)) of the Dutch national authority in PROJ 9.8.0. <o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-GB" style="font-size:11.0pt;font-family:"Arial",sans-serif"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-GB" style="font-size:11.0pt;font-family:"Arial",sans-serif">I suspect it has to do with the introduction of national realisations of ETRS89 in EPSG. Complicating factor is that EPSG erroneously removed the superseded label
from some outdated transformations (Amersfoort to ETRS89 (5) and Amersfoort to ETRS89 (6)). However, these old transformations have a lower accuracy than the official one, so I think PROJ should be able to still find the official transformation.
<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-GB" style="font-size:11.0pt;font-family:"Arial",sans-serif"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-GB" style="font-size:11.0pt;font-family:"Arial",sans-serif">Why can’t PROJ find it? Is there something else wrong in EPSG, preventing PROJ to find the official transformation? Or is this an issue in PROJ 9.8.0?<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-GB" style="font-size:11.0pt;font-family:"Arial",sans-serif"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-GB" style="font-size:11.0pt;font-family:"Arial",sans-serif">Jochem<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-GB" style="font-size:11.0pt;font-family:"Arial",sans-serif"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-GB" style="font-size:11.0pt;font-family:"Arial",sans-serif"><o:p> </o:p></span></p>
<p class="MsoNormal"><b><span lang="EN-GB" style="font-size:11.0pt;font-family:"Arial",sans-serif">Example 1: Forward<o:p></o:p></span></b></p>
<p class="MsoNormal"><span lang="EN-GB" style="font-size:11.0pt;font-family:"Arial",sans-serif">From the national ETRS89 realisation to the national projected CRS, PROJ uses the correct transformation Amersfoort to ETRS89 (9):<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-GB" style="font-family:Consolas">projinfo EPSG:11037 EPSG:28992 --spatial-test intersects -o proj --hide-ballpark<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-GB" style="font-size:11.0pt;font-family:"Arial",sans-serif"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-GB" style="font-size:11.0pt;font-family:"Arial",sans-serif">But from ETRF2000 and the ETRS89 ensemble PROJ doesn’t use the official transformation of the national authority anymore:<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-GB" style="font-family:Consolas">projinfo EPSG:9067 EPSG:28992 --spatial-test intersects -o proj --hide-ballpark
<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-GB" style="font-family:Consolas">projinfo EPSG:4258 EPSG:28992 --spatial-test intersects -o proj --hide-ballpark
<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-GB"><o:p> </o:p></span></p>
<p class="MsoNormal"><b><span lang="EN-GB" style="font-size:11.0pt;font-family:"Arial",sans-serif">Example 2: Reverse<o:p></o:p></span></b></p>
<p class="MsoNormal"><span lang="EN-GB" style="font-size:11.0pt;font-family:"Arial",sans-serif">From the national projected CRS to the national ETRS89 realisation, PROJ uses the correct transformation Amersfoort to ETRS89 (9):<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-GB" style="font-family:Consolas">projinfo EPSG:28992 EPSG:11037 --spatial-test intersects -o proj --hide-ballpark<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-GB" style="font-size:11.0pt;font-family:"Arial",sans-serif"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-GB" style="font-size:11.0pt;font-family:"Arial",sans-serif">But to ETRF2000 and the ETRS89 ensemble PROJ doesn’t use the official transformation of the national authority anymore:<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-GB" style="font-family:Consolas">projinfo EPSG:28992 EPSG:9067 --spatial-test intersects -o proj --hide-ballpark
<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-GB" style="font-family:Consolas">projinfo EPSG:28992 EPSG:4258 --spatial-test intersects -o proj --hide-ballpark<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-GB"><o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-GB" style="font-family:Consolas"><o:p> </o:p></span></p>
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