White balance is the single camera setting that decides whether the people in your shot look like real humans or boiled lobsters. It’s also the setting most easily ruined by Auto mode. Here’s what it does, why it matters, and how to set it on purpose.
What white balance actually does
A camera sensor doesn’t know what “white” is. Tungsten bulbs are orange; daylight is bluish; an overcast sky is bluer still. Without correction, a white shirt under tungsten light reads as orange on the sensor.
White balance tells the camera: “the light here is this colour - please assume that’s neutral white.” The camera then shifts the whole image to make a true white object render as white.
In numbers, white balance is expressed in Kelvin (K) - the colour temperature of the light source.
A quick Kelvin cheat sheet
| Light source | Kelvin |
|---|---|
| Candle / sunrise | 1800 - 2500K |
| Tungsten / incandescent bulb | 2800 - 3200K |
| Halogen / warm LED | 3000 - 3500K |
| Fluorescent (cool white) | 4000 - 4500K |
| Direct midday sun | 5200 - 5600K |
| Camera flash / 5500K LED | ~5500K |
| Overcast sky | 6000 - 7000K |
| Open shade, blue hour | 7000K+ |
When the camera is set to 5500K, it’s expecting daylight. If the actual light is tungsten (3200K), the sensor will record everything as too orange and the camera does nothing to fix it.
Why Auto White Balance fails on set
Auto WB looks at the scene and guesses. In a single frame, that’s fine. Across a scene, it’s a disaster:
- The actor turns their head and AWB shifts 200K.
- A car drives past with its headlights on and AWB jumps 600K.
- You cut between two takes and the wall colour changes.
For filmmaking and video, lock white balance to a specific Kelvin number. Use AWB only for fast, run-and-gun shooting where consistency doesn’t matter.
How to actually set white balance
You have three real options on most cameras:
1. Pick a preset
Tungsten, Daylight, Fluorescent, Cloudy, Shade. Fast, lazy, and usually wrong by a few hundred Kelvin.
2. Custom Kelvin (the right answer)
Switch the camera to manual / Kelvin mode and dial in the actual colour temperature of the light. To do this you need to know the Kelvin value - which is where a white balance meter app like KEV comes in. See the step-by-step guide.
3. Custom WB with a grey card
Point the camera at a properly lit grey card (or true-white sheet), press the custom WB button, and the camera computes the neutral point itself. Works well; needs the card in the actual scene light.
White balance vs tint
Kelvin is only half the story. The other axis is tint - the magenta/green shift. Fluorescents and cheap LEDs push the image green; some daylight pushes it magenta. Cinema cameras let you correct both; consumer cameras usually only let you set Kelvin.
A working setup
- Switch your camera off Auto WB.
- Open KEV and meter the dominant light.
- Read the Kelvin (and tint, if shown).
- Enter that Kelvin in the camera’s custom WB.
- Lock it. Don’t change it shot-to-shot unless the light changes.
That’s a deliberate, repeatable white balance you can match across cameras, locations and edit rooms - and it’ll save you hours in post.