We would like to analyze in the field of precision agriculture the performance of a lot of hybrids that are planted in lines with no border between them. For this we need to make boundary or a border for each hybrid when the plants are in their early stages so we can use this border template to detect the exact location of hybrids later on.

For this we've made an ortophotoplan (RGB) that has <1cm accuracy and defined polygon shapefiles in QGIS that we've exported as shapefile and then imported in Pix4D Mapper (Desktop) in the Index branch, but the drawn boundaries are shifted from the place they where in QGIS (or to the left or to the right).

Do you know what we could have done wrong?

Or is there another way to make boundaries that we can use?

The purpose of the boundaries is to be imported later on when the plants are developed and you can no longer distinguish where one hybrid starts and where it ends so we can be sure we're indeed analyzing the right hybrid and not stepping in the area of the next one (because the area covered by one hybrid is very small and there are maybe a few dozens types crammed into a single space with no visual border between them).

I want to mention that all the maps used to make the boundaries are cm level accurate and that we would like to import the boundaries to different maps that are cm level accurate (rgb ortophotoplans, multispectral maps, thermal maps).

Can you please help us figure out how to make the boundaries fall into the right place accurately across all types of maps?

  • When QGIS creates a shapefile, it puts the coordinate reference system in a .qpj file instead of the ESRI standard .prj format. Some GIS software doesn't know how to read the .qpj file, so the data loads with the wrong CRS. In these cases you have to set the CRS manually when you load the layer into that software. – csk Mar 15 '19 at 16:26
  • Is there any workaround this? – Alex Lungu Mar 15 '19 at 17:37
  • It sounds like the qpj file has more details than the prj file, as explained here in the QGIS manual. Software packages that can't read the qpj file, are missing some of the information that QGIS has access to. My suggestion is to try a simple coordinate system, eg EPSG:4326. It's a geographic coordinate system, so there's fewer details needed to specify it. – csk Mar 15 '19 at 17:57

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