The second example below uses a LDR (light dependent resistor) to indicatesome desired light level. The LDR has a large dynimic range and varies inresistance from less than 100 ohms on a cloudy day to over a megohm in totaldarkness. A 2K pot was used to adjust the window range for usual room lightconditions. This setup might also be used to indicate sunrise/sunset conditions.
Light Level Indicator Circuit Diagram
The proto board picture below shows the circuit wired to measure lightlevel using a LDR and 2K potentiometer. The green (window) LED is litindicating the light level is about right to take the picture.
Light Level Indicator Circuit Diagram
The proto board picture below shows the circuit wired to measure lightlevel using a LDR and 2K potentiometer. The green (window) LED is litindicating the light level is about right to take the picture.
