Legacy survey r-band (uppers panels) and Wise W1 3.4 µm (lower panels) magnitude versus the 0.5–2 keV (left panels) and 2–10 keV (right panels) X-ray flux for the eFEDS hard sample. Sources classified as being extragalactic (green symbols) and Galactic (purple symbols) are shown separately. As a comparison the data for the AEGIS-XD survey (Nandra et al. 2015) are shown (small black symbols), which cover slightly different bands in the optical–IR, specifically Subaru R_c and Spitzer IRAC 3.6 µm.