Kelvin, briefly

Color temperature describes where a white sits between warm and cool, in kelvin. Anchors worth memorizing: candlelight ≈1,900K. Tungsten stage lamps ≈3,200K. Daylight ≈5,600K. Lower = warmer, higher = cooler (yes, backwards from intuition — it's the physics of heated bodies). Correction gels exist to move between these worlds: CTO (orange) warms daylight down toward tungsten; CTB (blue) cools tungsten up toward daylight. This is why “warm white” at last call feels like a fireplace and full daylight white feels like getting arrested: you're moving the room thousands of kelvin.