One tap, two numbers
A colour cast is the light, not the subject. The picker reads the colour under your tap and solves the warmth (blue against yellow) and tint (green against magenta) that make that colour neutral. Those two numbers are written into the sliders below it, where you can read and move them, and undo takes them back.
- Warmth −100 to 100: left is cooler, right is warmer.
- Tint −100 to 100: left is greener, right is more magenta — the fix for fluorescent and some LED light.
- Saturation −100 to 100: −100 is black and white.
- Vibrance 0 to 100: dull colours move most, strong colours barely, skin tones least.
If the light rather than the colour is wrong, start with Auto fix a photo or Brighten a photo; Auto also reads a cast on the midtones. Named looks, hue mixers and object recolouring are not part of this tool.
Questions about colour
- What should I tap?
- Something that was really grey or white in the room: a wall, paper, a grey T-shirt, an overcast sky, the white of a fridge. Not a highlight that has blown to pure white and not a deep shadow — the picker refuses those, because they carry no evidence about the light. It reads a small square, not one pixel, so grain does not decide it.
- My indoor photos are yellow. Will this fix them?
- That is exactly the case it is for. A tungsten or warm LED bulb makes white walls yellow-orange; one tap on the wall writes a negative warmth (cooler) and a small tint, and the wall comes back neutral. Both numbers stay in the sliders, so you can warm it back a little if the room should feel warm.
- Can I make it black and white?
- Yes — Saturation all the way left is black and white. The white-balance pick still matters first, because a colour cast changes how the greys come out.
