When I create contours in Pix4D I am creating them as 1-foot contours both DSM and DTM and export in a .dxf format. I bring the contours into Microstation V8. I then bring in the orthomosaic created from the same Pix4D project. However, each time I do, Microstation shows the contours offset from the imagery. This is not the case if I bring the same data into GIS (they line up perfect). I also tried bringing the data into Global Mapper and the data was offset even worse. Global Mapper also indicated that the contour data had no projection assigned to it. However, the imagery does have a projection. I’m thinking that each software is trying to reproject the contour data into whatever coordinate system is set by the ortho but not doing a very good job of it. Any thoughts?
Hello Henry,
The contour lines that are generated by Pix4D are georeferenced and they refer to the selected output coordinate system, the same as the rest of the Pix4D outputs.
What kind of offset do you observe? Is it horizontal, vertical or in both directions?
Are you using the .dxf file for the Microstation V8 and the GIS software? Or are you maybe using the shapefile for GIS?
Could you please post here the quality report of the project and share with us the contour lines and the DSM/DTM files?
Regards,
I am actually having this same issue. When importing the orthomosaic into Civil3D it comes in properly located just as every other file produced from Pix4D. However, when I try importing the ortho and the dsm.tif file into an ArcGIS map, they come into the incorrect area horizontally. The contours for the dsm/dtm (shape file), come in the appropriate location. I have noticed that after importing the files there is an associated file in the file directory that is a .ovr file type.
Any guidance would be very much appreciated as I can’t really find anything online about this.
Thanks,
AJ Johnson
HI AJ. This sounds like a coordinate system issue. Can you double-check what the data is referenced to and ensure that you have the correct settings in ArcGIS?
Hey Holden (and everyone else for that matter),
I did have everything correct in ArcMap. The issue came from the Pix4D exported file. Though it was projected in the proper coordinate system, the spelling/abbreviations were slightly different than what ArcMap recognized. I decided to use the project tool on the raster image, selected what should have been the same coordinate system, and just like that, it moved into the correct location.
For additional context, the Coordinate system I am using as recognized by ArcMap is NAD_1983_(2011)_IaRCS_zone_5 while the exported information from PiX4D is NAD_1983_2011_IaRCS_zone_5. Just missing the parenthesis seems to have caused the issue.
Hope this helps someone out there.
Thanks,
AJ Johnson
Thanks for sharing. Yeah, that can happen. That’s why I recommend working with EPSG numbers or PRJ files in PIX4Dmapper to avoid these super subtle differences. Good on you for catching that. Thanks for letting us all know.