To evaluate the impact of coincidence loss due to overlapping detection events from multiple incident primary electrons, we performed numerical simulations in which 9 independent arrays of virtual counts were generated sampling a random temporal distribution of electron arrival on the pixel within a one second interval, defined by an incident electron flux on a pixel. The 9 independent arrays of incident electrons simulated a cluster of adjacent pixels. Each was sampled at the internal count rate, and the coincidence of counts across all nine was assessed per second. Each coincident pair of events within a pixel or between pixels in a cluster contributed to the count of lost electrons. That process was sampled in a thousand trials, each with a random temporal distribution of electron counts per pixel (Supplementary Script 1). Averages and standard deviations were calculated and plotted for the measured e -/pix/s and the corresponding lost count of e -/pix/s (Figure , Supplementary Figures ).