What causes Camera Location error?

[iaerobotics]

The final optimized chunk with imported laser scan and generated point cloud is shown in attached image screen.   What did you define as your camera position accuracy?

Not really sure. I don't enter any accuracy other than "Highest/High/Medium/etc) in the alignment drop down.

This is my workflow - the same one I used with the old unit that produced errors in the mm range.

I create a new project
I ADD FOLDER and add all the images
I remove the images from takeoff and calibration and the return to land images
I select "Align Photos" with the following options - SEE ATTACHED IMAGE
When that is done I "Build Point cloud"
When that is done I "build DEM"
When that is done I build orthomosaic
When that is done I export and load into GLobalmapper with the Point Cloud and they lined up perfectly...

With this new unitl its all over the place and I have to rectify the ortho based on the lidar like I used to have to with older previous lidar units.

I am ok doing more, and importing more accurate pitch/roll/yaw data if I have to but even with that on my end I did not get nearly the results you did or the results I used to get with images from the previous unit doing the exact same thing.

[Paulo]

Once again,

you did not check the angle box in reference pane... That is why there is a rotational effect in your alignment as all camera airborne control is on a  line (one line pass).

And modify camera accuracy, selecting them and using right click context menu. This tells the program to use higher weights on camera positions to reflect their ppk accuracy. You do not need to import external file as the exif values for positions and angles are already the ppk ones...

If you need consulting, do contact me by PM.

[iaerobotics]

Once again,

you did not check the angle box in reference pane... That is why there is a rotational effect in your alignment as all camera airborne control is on a  line (one line pass).

And modify camera accuracy, selecting them and using right click context menu. This tells the program to use higher weights on camera positions to reflect their ppk accuracy. You do not need to import external file as the exif values for positions and angles are already the ppk ones...

If you need consulting, do contact me by PM.

I did check the rotation box and process, I just did not screen shot that one. It makes a slight improvement but not much at all.

However, you did strike on an item that did work. By changing the accuracy to .005 it now produces error in the mm range and aligns with the point cloud like the previous units images allowed.

Now, I still don't know why I have to change the accuracy on the images from this new unitl when the other one produced results in the mm of error range with it left default at 10m but this is a small thing and we will do this to future projects.

Thanks again for working through this with me. Although we didnt get to the root cause, we got to a solution that will work for us moving forward. Appreciate all the time and help!

[Paulo]

Hi iaerobotics,

is it possible that somehow the old unit wrote, apart from the ppk image position and orientation, the position accuracies into the image XMP metadata? as in attachment...Then the position accuracies would be read during image import by Metashape as long if you have set this option in preferences/Advanced tab menu...In your case the ppk accuracies in the cm or sub cm level...

[iaerobotics]

Hi iaerobotics,

is it possible that somehow the old unit wrote, apart from the ppk image position and orientation, the position accuracies into the image XMP metadata? as in attachment...Then the position accuracies would be read during image import by Metashape as long if you have set this option in preferences/Advanced tab menu...In your case the ppk accuracies in the cm or sub cm level...

I thought of that but I went back and looked at the projects from the previous unit and accuracy was all set to 10m. I still think the lever arm settings or something is different and the geolocation is not ac accurate on the images as the last unit and because of that Metashape has an issue with it until we tell if manually the images are highly accurate. ??