Drone photogrammetry: from the flight to a georeferenced 3D model.

What is photogrammetry?

Photogrammetry is the technique of measuring an object from photographs. When the same point appears on several images taken from different angles, its position in space can be computed, just as our two eyes do. Repeated over millions of points and hundreds or thousands of photos, this computation produces a dense point cloud, then a photorealistic textured 3D mesh.

Modern 3D photogrammetry is fully digital: software automatically matches common points between images, computes the position of each shot and rebuilds the geometry. The quality of the result depends above all on the quality of the capture: photo resolution, overlap between images and georeferencing.

Why use a drone?

The drone puts the camera where it matters: above roofs, in front of high facades, around a bell tower, above a plot of land or an entire village. Drone photogrammetry avoids cherry pickers and scaffolding, covers large areas in a few flights and combines with ground photography for interiors and details.

For large areas, our flight plans are computed by SmartWaypoints, our flight planning platform: altitude follows the terrain for a consistent resolution, and flights can be repeated to monitor a site over time.

How accurate is it?

A photogrammetric model is only accurate if it is properly tied to the ground. We set out control points measured by RTK GNSS to the centimetre. Some are used for georeferencing, the others as independent checks. The result: 1 to 3 cm accuracy, documented in an accuracy report, in your project's coordinate system (Lambert 93, CC 9 zones, WGS 84, UTM or local grid).

What a photogrammetric survey produces

• Point cloud (LAS / LAZ, E57, PLY) and textured 3D mesh (OBJ, FBX, glTF, 3D Tiles)
• Georeferenced orthophotos, DSM / DTM and contour lines
• Plans, sections, elevations and facade ortho-images
• Measurements, areas and volumes
• Publication in the Visuoz viewer to measure and share online

A controlled regulatory framework

Our flights are carried out by a certified remote pilot for all categories and scenarios (A1 / A2 / A3, STS-01 / STS-02, S1 / S2 / S3). We check restricted areas and handle the necessary declarations and authorisation requests; all you need to provide is the site owner's consent.