Is the light on a Lutron dimmer?
If so, you could set it to, say 50%, add a motion sensor and set it to come on to 100% when motion is detected, then back to 50% when not.
You could also have it slowly dim to 0, say for 10 minutes after you reach the 4 hour mark instead of just abruptly shutting its off.
You could also, with a motion sensor, have it turn on to 100% when motion is detected between sunset and sunrise.
