Indoor photos look orange because the light is orange: incandescent and warm-white LED bulbs burn at roughly 2700–3200K, your camera’s auto white balance assumed daylight (~5500K), and the difference lands on the sensor as a warm cast. The fix is the warmth slider moved negative — typically −20 to −40 — which pushes red down and blue up by exactly the axis the cast lives on.

The Kelvin explanation, without the physics degree

Color temperature describes which way a light source leans on the orange↔blue axis. Counterintuitively, low Kelvin numbers mean warm (orange) light:

Light source	Approx. temperature	Cast in a daylight-balanced photo
Candle	~1800–2000K	Deep orange
Incandescent / warm-white LED	~2700–3000K	Orange — the usual culprit
Halogen	~3000–3200K	Warm orange
Office fluorescent / cool-white LED	~4000–5000K	Mildly warm, often greenish
Direct daylight	~5500–6500K	Neutral — what AWB expects
Overcast sky	~6500–7500K	Slightly cool/blue
Open shade	~7000–8000K	Noticeably blue

Auto white balance works by guessing “the brightest thing is probably white” — reliable outdoors, where scene content averages near neutral. Indoors under one dominant bulb, the guess fails both ways: either the camera locks onto daylight and records the orange faithfully, or it half-corrects and leaves a muddy in-between.

The fix: warmth, and how much

In the editor, warmth is a channel rebalance — at −50 it shifts red −20 and blue +20 per pixel (the exact math is in the slider formulas). Practical amounts:

• Mild cast (mixed daylight, “soft white” LEDs): −10 to −20
• Typical living-room incandescent: −20 to −40
• Heavy cast (halogens, candle-lit, restaurant): −40 to −70 — at which point watch for gray skin and clipped blues

The correct stopping point is a known white in the frame — a plate, a shirt, a wall — looking neutral rather than blue. If whites go cold, you’ve traded an orange cast for a blue one.

The cases warmth can’t fix

Two honest limits. Mixed lighting — warm lamp plus window daylight — has no single correct warmth; correct for the light falling on your subject and let the background go its own way. Fluorescent green — many cheap fluorescents cast green-orange rather than pure orange, and warmth moves only the orange-blue axis. If a photo stays sickly after warmth bottoms out, the cast isn’t orange and no amount of warmth will remove it.

For the broader problem-to-slider map — haze, flatness, washed-out color — see which adjustment fixes which problem; for the exact per-pixel warmth math, the slider formulas document it in order.

Frequently asked questions

Why do my photos look yellow or orange under indoor lighting?

Because the light genuinely is orange. Incandescent and 'warm white' LED bulbs emit light around 2700–3200K — strongly red-weighted — while your camera's auto white balance was tuned for ~5500K daylight. The camera records the orange light faithfully and renders neutral objects orange. Outdoors your eyes and the sensor correct for it; indoors, with a single warm source, nothing corrects it.

How do I fix orange indoor photos?

Pull the warmth slider negative — start around −20 and work toward −40 for strongly orange shots. In PhotoFilter, warmth −50 shifts the red channel −20 and blue +20 per pixel, which is a direct counter-rotation of the tungsten cast. Stop when whites look neutral, not blue; overshooting just relocates the cast. Open the editor, drop the photo, drag warmth left while watching a known-white object in the frame.

What color temperature is indoor lighting?

Household incandescent and 'warm white' LED: 2700–3000K. Halogen: ~3000–3200K. 'Cool white' LED and office fluorescent: ~4000–5000K. Overcast daylight: ~6500–7500K; open shade can reach 8000K, which is why shade photos go the other way — blue. The lower the Kelvin number, the warmer (more orange) the light.

Why is my photo still orange after lowering warmth?

Two common causes. First, mixed lighting — a warm lamp plus daylight from a window means no single warmth value is correct for the whole frame; correct for the subject's light and accept the rest. Second, fluorescent casts aren't pure orange — cheap fluorescents skew green-orange, and warmth fixes the orange axis only. A residual green tint needs the kind of tint/magenta channel this editor deliberately doesn't fake; re-shoot or live with a slight cast.

Should I fix white balance in camera or in editing?

In camera when you can — a correct white balance at capture preserves maximum channel data, while post correction discards part of the red channel to rebalance. Shooting RAW makes post white balance nearly free. For JPEGs already shot orange, warmth correction in editing is the fix you have, and at −20 to −40 the quality cost is invisible at normal viewing sizes.