Top panels: CMD using Gaia photometric filters (left) and using OmegaCAM filters (right). The black points show the one-degree region from the ONC center and the red points the inner 0.2° region. Clearly, the Gaia photometry in bp and rp filters is affected by the central crowding. Bottom panel: RA and Dec plot showing the one-degree region and the 0.2° central selection (red points). In all panels, the black points are the C1 and 2-σC2 selected objects.