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Empty area

Hi guys,


After merging project together and solved some accuracy errors with MTP, I get empty area on my building roof.


Can someone explaining that ?


Thank you! 


Hello Benjamin, 


  • How did you merge the sub-projects?
  • Did you add MTPs before merging?
  • Were the points visible in the sub-project before merging? 


The recommended procedure to merge two projects is:

  1. Create sub project A
  2. Process step 1.
  3. Add 6-10 Manual Tie Points , for example, pp1, pp2, pp3, pp4, pp5…
  4. Mark each Manual Tie Point on at least 3 images and Reoptimize
  5. Create sub project B
  6. Process step 1.
  7. Add the same 6-10 Manual Tie Points created in the sub project A and give them the same names as in the sub project A (pp1, pp2, pp3, pp4, pp5…)
  8. Mark each Manual tie point on at least 3 images and Reoptimize
  9. Merge the projects by creating a new project: 202558529
    The software will ask if the Manual Tie Points with the same name are the same in the two projects, click YES
  10. Process the steps 2 and 3 if desired.

Best Regards, 


Thank you for your response and explanations.

To merge sub-projects (1 aerial, 1 terrestrial),  I created identical MTP on both, and created a new project to merge them.



Roof points was visible only on aerial project (obviously…)

But on the terrestrial project I annotated the sky (carve option), and due to a bad accuracy, I think it erase some points from the Aerial project… 


So I think this issue is due to my annotations…


Maybe It’s better to merge projects together in a first time and then use the annotation option…