Ldr relay switch with 555

Been experimenting with using a 555 to switch a relay depending on light levels. Been a long time since I played with circuits like this! The idea is the switch a relay depending on light levels to operate a motor to open and close blinds. I don't want it to react too quickly to sudden changes in light level, this is what I've come up with so far. The bottom potentiometer represents the ldr. The top one tunes how the circuit switches. I don't want it to react too quickly to sudden changes in light level, the capacitor across the ldr does this, (sort of), it slows the reaction to switching the relay on but not when switching it off if light levels suddenly increase. Any ideas how to slow the reaction to switching off?

published 10 years ago