This paper presents the recent developments of ARGOS, a GNC experimental facility at Politecnico of Milano, at the premises of the Aerospace Science and Technology Department (DAER). The purpose of the facility is the testing of novel image-based Guidance, Navigation and Control (GNC) algorithms for autonomous navigation in proximity of a known or unknown uncooperative target. The facility calibration is presented, along with the set-up for the a moon landing and debris fly-around scenario, as representatives of the facility possibilities. In the paper the capability of reproducing realistic and high fidelity images in different operating conditions is verified, by means of a validation process based on synthetic ground truth images.