SfM Point Cloud
Definition
A 3D point cloud derived from overlapping photographs using Structure from Motion photogrammetry. Achieves similar resolution to terrestrial LiDAR at close range but cannot penetrate vegetation canopy.
- Derived from
- Overlapping photographs via Structure from Motion
- Resolution
- Comparable to terrestrial LiDAR at close range
- Limitation
- Cannot penetrate vegetation canopy
- Output
- 3D point cloud
Common questions
Why can't an SfM point cloud see through vegetation the way some LiDAR can?+
SfM relies purely on visible-light photographs, so it can only reconstruct surfaces the camera actually sees; it lacks the penetrating pulses that airborne LiDAR uses to catch partial returns through canopy gaps to the ground below.
When would an investigator choose SfM over terrestrial LiDAR?+
SfM only needs a standard camera and overlapping photographs rather than a dedicated scanner, making it faster and cheaper to deploy for close-range scene documentation when canopy penetration is not required.
Related terms
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- Ground Classification
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- LiDAR
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- Micro-Topography
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- Point Cloud
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