High‐contrast TV images of living cells are recorded from a light microscope. The video line signal is converted to binary and used to gate a 12.5‐MHz clock driving a counter. After completion of each video frame the accumulated counts (proportional to the dark image area) are written onto a stack (FIFO) before the counter is reset. Thus, area information is actualized at a rate of 50 values per second and can be read out at speeds suitable for computer interfacing and (after D/A conversion) oscilloscope displays or paper chart recording. With two counting channels the time course of two areas of distinctly different gray shades can be recorded at once.