Tests for the validity of Omega. We confirm that the code successfully produces fundamental particle orbits, such as the ones mentioned in Sect. 2.1. In each picture we have the BH situated at the axes origin and with gray is its event horizon. In (a) we have in red the photon ring produced numerically by the code and on top of it, in the black dashed circle, its theoretically expected position. In (b) we see in blue the ISCO produced numerically and on top of it, in the black dotted circle, its theoretically expected position. In (c) we set the BH mass M = 0 (with light gray showing where its horizon would have been) and examine the trajectory of a photon. With any BH mass M >  0, the photon would have to infall and cross the event horizon, but with no BH mass present, the spacetime is Minkowski and the photon travels in a straight line.