CO3D Image Quality Calibration

Abstract. The launch of the four CO3D satellites took place on 25th July 2025. One of the goals of the mission is to generate a worldwide, accurate and low-cost Digital Surface Model (DSM) at a resolution and relative height accuracy of 1m. This 3D performance relies on well-controlled image quality: the radiometry and resolution ensure a performant matching between the stereo images, and the geometry guarantees an accurate altimetry. The Image Quality In-Orbit Test (IOT) phase has permitted to tune the on-board parameters before starting the massive acquisitions. Dedicated acquisition modes were used on calibration sites spread throughout the world. Thanks to the agility of the satellite, celestial acquisitions are possible and support the radiometry and resolution calibrations. This paper does not include the in-orbit performances due to confidentiality agreement.