Plot shows the ratio of detected to detectable sources in the 1.2″ resolution image as a function of flux density, based on the 6″ resolution LoTSS deep field catalogue. Sources from the 6″ resolution LOFAR deep field ELAIS-N1 catalogue are considered detectable if their peak intensity exceeds 5.5 times the RMS at the same coordinates in our 1.2″ resolution ELAIS-N1 image. The blue dots demonstrate this ratio. Uncertainties are estimated using the $\sqrt{N}$ method and propagated accordingly.