Good question, the difference is between dawn/dusk and sunset/sunrise. Let me explain;
After sunrise and after sunset are based on the exact moment the sun crosses the horizon.
So:
- After sunrise = from the moment the sun rises until it sets
- After sunset = from the moment the sun sets until it rises again
That’s purely based on the sun being above or below the horizon, being 0°.
Daytime is slightly different. That one is based on civil twilight (civiele schemering in Dutch 
). Homey defines daytime as the period between dawn and dusk, where dawn is when the sun is 6° below the horizon in the morning, and dusk is when it’s 6° below the horizon in the evening.
That means:
- Daytime starts a bit before the actual sunrise
- Daytime ends a bit after the actual sunset
So “daytime” is always slightly longer than the period between sunrise and sunset.
In practice:
If you want something to follow the exact sun-up / sun-down moment, use sunrise/sunset.
If you want it to follow when there’s already (or still) natural light outside, daytime is usually the better choice.
I hope that explains it!
