Photogrammetry in land surveying
Photogrammetry is a measurement technique using photos to calculate distances, volumes, and shapes. By combining images from different viewpoints, accurate 2D maps and 3D models of terrains, buildings, and structures are created.
Within land surveying, photogrammetry is often used to map large areas quickly and efficiently, with a level of detail that was previously only achievable through intensive field work.
What is photogrammetry?
Photogrammetry uses cameras, often mounted on drones, to collect overlapping images. These images are then processed using software into measurable datasets, such as:
- scaled orthophotos
- 3D point clouds
- digital terrain and elevation models
⚠️ Important: photogrammetry works above the water surface.
For underwater measurements, bathymetry is used, which is a different measurement technique using sonar.
The added value of photogrammetry
Accuracy and detail
Photogrammetry provides highly detailed measurement data, suitable for analysis, design, and monitoring. Complex shapes and hard-to-reach areas are fully captured.
Efficiency and speed
Large sites or construction projects can be surveyed in a short time, keeping time on-site limited and allowing projects to progress faster.
Versatile applications
Photogrammetry is used for land surveys, volume calculations, site monitoring, facade measurements, cartography, and urban planning applications, among others.
Environmentally friendly
The method is non-invasive and ideal for ecologically sensitive areas, as physical disruption is kept to a minimum.
Photogrammetry versus other measurement techniques
Photogrammetry is not always the best solution. Depending on the project, another technique may be more suitable:
- Bathymetry → for underwater bottom measurements
- 3D laser scanning → for high accuracy indoors or with complex structures
- Classic land surveying → for legal boundary determination
In practice, these techniques are often combined.
Typical applications of photogrammetry
- Volume determination of stockpiles and earthworks
- Facade measurements without scaffolding
- Urban planning and cartography
- Monitoring of infrastructure such as bridges and roads
- Documentation of heritage and archaeological sites
Photogrammetry in practice
Photogrammetry provides raw measurement data that is subsequently processed into usable output. The quality of the final result depends not only on the images but also on:
- flight planning
- overlap and resolution
- ground control points
- processing and interpretation
Therefore, photogrammetry within land surveying is more than just “a drone flight.”
Want to know more?
Would you like to know if photogrammetry is suitable for your project, or when another measurement method would be a better fit?
Please feel free to contact us for further information or advice.