General tips:

  • Camera. Use a digital camera with reasonably high resolution. The resolution affects the quality of the processing result.
  • Camera position:
    • Avoid large camera inclinations from the horizontal plane (more than 45 degrees). Otherwise, the image frame space will not be used effectively concerning the target object.
    • The camera track should be parallel to the surface of the object during shooting.
    • Flying closer to the object of interest will improve the quality of the reconstructed surface and texture.

  • The number of photos. More than required is better than not enough. Excessive images can be disabled during processing.
  • Markers. If the drone does not have a high-precision receiver onboard, it is recommended to add markers measured with topographic instruments when preparing for data capture. The markers can be used for alignment optimization and referencing tasks.
  • Weather. It is recommended to plan the data capture process for a cloudy day. Direct sunlight leads to patches on most of the surfaces; the light patches which have moved across the target object during the shooting process will create difficulties for reconstruction algorithms.


How to shoot a building?

  • Capturing scenarios. 

The following figures illustrate CORRECT capturing scenarios:

Facade
Interior


The following figures  illustrate  INCORRECT capturing scenarios:

Facade
Interior
  • How to shoot the corners of a building? At the corners of a facade, when moving from one wall to another, it is recommended to take photos with more-than-average overlap to ensure the maximum number of connecting points for the walls forming the corner.
  • Avoid reflections and highlights. If the facade material is characterised with a large reflection coefficient (siding, polished stone, steel, etc.), it is recommended to use a circular polarizing filter to avoid reflections and highlights.
  • Identical details on the object. The pictures below show the left and the right parts of a building, respectively. Increasing the number of unique elements (it might be worth adding markers to the facade) and maintaining a high overlap ratio will help to fix the issue when the different parts of a building look similar as in the photos below:



How to shoot an isolated object?

  • Capturing scenarios. The following figures illustrate incorrect and correct capturing scenarios for such isolated objects as statues and monuments:
Incorrect
Correct
  • Apply masks. To achieve good reconstruction results, it is recommended to Mask all irrelevant elements on the source photos (background, accidental foreground, moving objects, etc.).