Photogrammetric 3D Scene Model
Definition
A three-dimensional spatial reconstruction of a scene produced by photogrammetric processing of overlapping photographs, typically captured by drone. Treated by courts as a documentary exhibit subject to the same admissibility threshold as conventional photography; requires an expert witness who can attest to the method's accuracy.
- Output
- 3D spatial reconstruction from overlapping photographs
- Typical capture
- Drone-acquired imagery
- Legal treatment
- Documentary exhibit, same threshold as conventional photography
- Requirement
- Expert witness attesting to method accuracy
Common questions
Why does a photogrammetric model need expert testimony to be admitted?+
Because the model is a computed reconstruction rather than a direct photograph, a court typically wants someone qualified to explain the software's process and validate that the resulting measurements and geometry accurately represent the real scene.
What advantage does a drone-based photogrammetric model give over ground photographs alone?+
Overlapping aerial images capture the whole scene from many angles, letting the software generate a measurable, navigable 3D model that preserves spatial relationships a series of flat photographs cannot show as clearly.
Can measurements taken from the 3D model be relied on for distances at trial?+
Yes, provided the capture and processing followed a validated workflow with known accuracy limits, since photogrammetric models can support accurate metric measurements when properly calibrated and referenced.
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