Release rate Ṙ for an example pixel derived from an LED flat with a subsequent series of dark exposures. The data points show the persistence signal P in the dark images with the bias pedestal (1024 ADU) subtracted and normalised by the exposure time and initial signal S . The horizontal error bars mark the beginning and end of each dark exposure. The best-fit power law (A = −1.215, B = −1.829) is shown in blue.