Photo exposure timer

The circuit working principle of the device is shown in Figure 5. AN in the circuit is the start button. After the power is turned on, the exposure lamp H is off. Press the button AN and the lighting lamp H will light up immediately. After a period of time, H will automatically go out. The circuit has 4 timing values, and the timing time is determined by 1.1RC, where R is the resistance value of the four gears R1-R4. C should use tantalum electrolytic capacitors to improve its timing accuracy. According to the values ​​shown in the figure, the timing value of gear 1 is 0.11s; the timing value of gear 2 is 1.1s; the timing value of gear 3 is 5.6s; and the timing value of gear 4 is 11s. You can determine it according to your actual needs.