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.
“I shoot RAW, so it doesn’t matter” - mostly wrong
This is the most common misconception about white balance, and it is half true.
In a RAW file, the white balance you set is stored as metadata. The sensor data underneath is untouched, so you can slide Kelvin anywhere in Lightroom, Capture One or Resolve afterwards with no quality penalty. That part is real.
Here is what it does not save you from:
- Video. Almost nobody shoots RAW video. ProRes, H.264, H.265 and most log formats bake white balance into the file. Get it wrong and you are correcting an already-processed image.
- Consistency. Fixing one frame is trivial. Fixing 400 frames that each drifted a little because AWB was on is a colour-matching job, not a slider move.
- Your judgement on set. If the monitor is 800K off, you light to the wrong reference. Contrast and gel choices get made against a false image.
- Tint. RAW converters give you a tint slider, but you have to know what neutral was. Nothing in the file records what the light actually did.
- Clipping. A badly wrong white balance can push one channel into clipping before the others. Blue skies under a tungsten setting are the usual casualty, and no slider brings a clipped channel back.
Shoot RAW and set white balance properly. The RAW file is insurance, not a substitute.
White balance by situation
| Scene | Start at | Watch for |
|---|---|---|
| Midday sun | 5500K | Skin picks up green from grass and foliage bounce |
| Overcast | 6500K | Flat light; warming slightly reads as more flattering |
| Open shade | 7000 - 7500K | Lit by blue sky, much cooler than people expect |
| Golden hour | 3200 - 4500K, falling fast | Re-meter every few minutes or the look drifts |
| Blue hour | 8000K+ | Setting it “correctly” removes the blue you came for |
| Tungsten interior | 2800 - 3200K | Bulbs vary; a dimmed bulb drops several hundred K |
| Fluorescent office | 4000 - 4500K | Heavy green tint - Kelvin alone will not fix it |
| Mixed window and interior | Meter the key | A 4000K spread is normal; gel or accept one skewing |
| Snow | 6000 - 7000K | Snow is a giant blue-sky reflector; auto goes cold |
| Concert / stage | Locked, manual | Coloured wash lights make AWB useless |
These are starting points, not answers. The reason to meter is that the actual number in the actual room is routinely several hundred Kelvin off the textbook value.
Warming and cooling on purpose
Correct white balance renders neutrals neutral. That is a technical target, not always an aesthetic one.
Once you have the metered number, deliberate offsets become repeatable:
- +200 to +400K over metered: warms skin, flatters most people, reads as sunlight even indoors.
- -200 to -400K: cools the image, useful for night interiors, moonlight and anything meant to feel clinical.
- Split the difference in mixed light: with a 3200K key and a 5600K window, setting 4200K leaves the key gently warm and the window gently cool - often more pleasant than neutralising either.
The point is that a deliberate offset from a known value is a look you can reproduce tomorrow. An unknown offset from an unknown value is just a mistake you happened to like.
Getting two cameras to match
Multi-camera work is where white balance stops being cosmetic. Two bodies on Auto WB will not match, and no amount of grading fully rescues them.
- Meter the key once.
- Enter the same Kelvin and the same tint on both bodies manually.
- Shoot the same grey card on both, back to back, at the head of the card.
- Compare the two on a waveform or vectorscope, not by eye on the camera screen.
- If one body reads consistently warm, offset it in-camera rather than fixing it later - Canon and Sony sensors genuinely differ at the same nominal Kelvin.
That grey card frame at the head of every setup costs five seconds and is the single most useful thing you can hand a colourist.
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.