RealityCapture custom Ground Plane compatibility

Sometimes, after aligning images in RealityCapture, your model may be misaligned with the ground plane, i.e., not properly oriented or aligned with the grid.

One possible solution is to set the Camera Prior pose > Absolute pose to "Unknown" for images lacking highly accurate GPS geotags and then rerun the alignment process.  Low accurate GPS geotags will often occur when using a drone that doesn't have RTK or capturing areas that may have high GNSS interference.

If rerunning the alignment step doesn't resolve the issue, you might consider setting more, or even all, images to "Unknown."  For future captures, it's recommended to take an orbit of oblique photos around your subject that also captures the real-world ground.  So, for example, if you're trying to capture the roof of a building, it's a good idea to take an orbital photograph of the entire building from a greater distance, ensuring that the ground is also included in the shots.

Another approach to resolve the issue is to manually define the Ground Plane in RealityCapture by using Tools > Set Ground Plane.  However, this method will orient the model in a way that is incompatible with georeferencing in both RealityCapture and Nira.app.

If you choose to use a custom Ground Plane in RealityCapture, be sure to set the Coordinate system to local:1 - Euclidean before exporting or uploading to Nira.

When using the Nira upload feature in RealityCapture, disable "Use UTM Zone..." and click "No" when asked to use a UTM coordinate system.