Loading Data from two sources with different projection

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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

geomannie

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.

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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.

The "Federal Office of Topography swisstopo" provides a tool for translation. That works fine. I expected that GlobalMapper does the same but obviously not.

Thanks Rainer