Everyone obsesses over getting to hagia sophia at 9am opening but honestly the afternoon light streaming through those massive windows is way better for seeing the byzantine mosaics. Plus you're not fighting german tour groups who've been caffeinated since dawn

The golden light hits the apse mosaics around 4pm and makes the whole space glow. You can actually take photos of the mihrab without random elbows in the frame. Counterintuitive but works perfectly for us non-morning people who'd rather sleep off the previous night's raki