RMSE Accuracy Report

Reconstruction accuracy: For each target, the tagged pixel positions across multiple camera images are triangulated through the reconstruction's camera models to produce a 3D position. This is converted to the survey CRS via proper geodetic conversion (ENU→ECEF→lat/lon→projected). The residual (dH, dZ) is the difference between this triangulated position and the GNSS survey coordinate. Reconstruction accuracy reflects the internal geometric quality of the photogrammetric solution, not the orthophoto.

Orthophoto accuracy: Target positions were tagged in the orthophoto and compared to GNSS survey coordinates. The residual (dH) is the horizontal distance between the tagged orthophoto position and the survey coordinate.

GCP (Ground Control Points) were used in ODM's bundle adjustment — the reconstruction was optimized to fit them. Their residuals indicate control fit quality. CHK (Check Points) were withheld from the bundle adjustment — their residuals are an independent measure of accuracy.