Loading Data from two sources with different projection
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Global Mapper UserTrusted User
Hi there
In Switzerland we changed the coordinate system lately. So we have to deal with different systems all the time.
I have vector data with the projection "PROJ_DESC=Swiss Grid / CH1903 / meters PROJ_DATUM=SWISS GRID (CH1903)" and another source with data with the projection "PROJ_DESC=Swiss Grid (LV95) / CH1903+ / meters PROJ_DATUM=SWISS GRID (CH1903+)"
When I load the two sources in the respective projection I get a small shift in the position.
What is Global Mapper doing? It seems that there is a transformation because the x/y-coordinates are totally different in the two sources.
How can you explain the small shift in my case x 0.8m y 0.15m?
Do I oversee something?
Thank you.
Rainer
In Switzerland we changed the coordinate system lately. So we have to deal with different systems all the time.
I have vector data with the projection "PROJ_DESC=Swiss Grid / CH1903 / meters PROJ_DATUM=SWISS GRID (CH1903)" and another source with data with the projection "PROJ_DESC=Swiss Grid (LV95) / CH1903+ / meters PROJ_DATUM=SWISS GRID (CH1903+)"
When I load the two sources in the respective projection I get a small shift in the position.
What is Global Mapper doing? It seems that there is a transformation because the x/y-coordinates are totally different in the two sources.
How can you explain the small shift in my case x 0.8m y 0.15m?
Do I oversee something?
Thank you.
Rainer
Answers
-
I am no expert of Swiss coordinates, but does this help? https://www.swisstopo.admin.ch/en/knowledge-facts/surveying-geodesy/new-coordinates/key-information.html
It suggests that there an expected shift with a maximum difference of 3m between the old LV03 and new LV95 coordinate systems.
-
geomannie said:I am no expert of Swiss coordinates, but does this help? https://www.swisstopo.admin.ch/en/knowledge-facts/surveying-geodesy/new-coordinates/key-information.html
It suggests that there an expected shift with a maximum difference of 3m between the old LV03 and new LV95 coordinate systems.
Thanks Rainer
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