Processing area import to wrong location

Hello,

i have a shp file with polygon in CAD software but if i import this area to pix4d, its is in the wrong location (like 50-100 m shift).

Do you know why this is happening?

Thanks

Hi,

This is usually occurring when the coordinate systems of the layers are different. Please make sure that the correct coordinate system was selected for the shapefiles.

Best,
Teodora

I set the same coordinate system for the shapefile and project in Pix4d. It can cause some transformation error?

Hi,

Could you first please overlay the shapefile on the orthomosaic by using QGIS? Is the same shift occurring also in this software?

Cheers,
Teodora

No.

QGIS

Detail of shift in pix4D

If you get me the URL for WMS i can use same base map like in Pix4D for this check.

Hi,

We use MapBox as a basemap layer.

I tried to replicate the issue by creating a polygon in QGIS and it seems that it got imported in the right place in Pix4Dmapper:


I used the same coordinate system (EPSG 32632) and got the result that I expected. However, this might not always be the case, depending on the coordinate system. I would strongly suggest checking the coordinate system definition, as some of them might be updated in AutoCAD and not in Pix4Dmapper or vice-versa (we usually adopt the definitions from the external database from https://spatialreference.org/).

Cheers,
Teodora

Hmm, and do you have some idea how to place my shp to correct position?

Hi,

I will recommend you to move the shapefile in QGIS (source: Can't move polygons in QGIS - Geographic Information Systems Stack Exchange)

  1. You need to ensure that the polygon is in Toggle Editing mode.

  1. Go to Edit > Move feature.

  1. Go to the polygon and move it in the desired direction by using the left-click.

I hope this helps.

Best,
Teodora

But in QGIS position is fine. The shift is after import to Pix4D.

Hi,

You cannot shift it in Pix4Dmapper. The only solution is to do it externally so that it is placed correctly during the importing in Pix4Dmapper.

Maybe other users have better ideas…?

Cheers,
Teodora