Saint-Élie: 625 hectares without a GNSS station within twenty kilometres
3.5 cm orthophoto of 625 hectares around an inland village, registered on a base and five control points measured by precise point positioning, with no reference station in range.
Background
Saint-Élie is an inland municipality of French Guiana, in the forest south of Sinnamary. For its development projects and the monitoring of its land holdings, the municipality wanted an orthophoto map of the village and of some 600 hectares around it. The nearest station of the permanent GNSS network is more than twenty kilometres away, too far for reliable real-time correction.
What we did
For the acquisition of 28 August 2024, six points were measured by precise satellite positioning: the location of our base station, observed for 45 minutes, and five control points, observed for 30 minutes each. The base then corrected the drone throughout the flights: 120 m height, 80% forward and 70% side overlap, north-south lines at 14 m/s. The 5,211 photos give a 3.5 cm per pixel orthophoto; the position error is 1.77 cm on the cameras and 2.22 cm on the control points. The mission report includes the six GNSS measurement reports.
In the mission log
625-hectare orthophoto around the village of Saint-Élie
Acquisition on 28 August 2024: 5,211 photos and a 3.5 cm orthophoto, registered on a base station and five control points measured by precise point positioning (PPP), with no permanent GNSS network station within 20 km.
- 625 ha
- 3,5 cm per pixel
Gallery
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97310 Kourou
French Guiana
Route des Trois-Îlets
97229 Les Trois-Îlets
Martinique
20030-041 Rio de Janeiro – RJ
Brazil