How you do call certain CCTs of the lights?

rngwn · 2019-04-05T13:40:34.000Z

I have been looking for the dividing lines between “neutral white”, “daylight”, “pure white”, “cool white” and “cold white” to no avail.

On fluorescent lamps, we call 3000k “warm white”, 3500k “neutral white”, 4000k “cool white”, 5000k+ “daylight” (with some vendors might call 5000k “sunlight”/”natural white”, and 6500k “cool daylight”)

For LEDs, the vendors usually call 4000k “neutral white”/”natural white” and 6000k+ “cool white”

Things start to get confusing for me on the CCTs between 4000k-6000k where the terms starts to mixed up.

- Some may call 5000k “natural white” or even “neutral white”

- 5000k and 5700k may also be called “pure white” (which sometimes chinese seller also use “pure white” to describe 6000k LEDs)

5700k may also be called “daylight balanced” on some of the fluorescent bulbs.

I would like to ask you all how do you name the CCT as “neutral white” “daylight” “cool white” etc. Particularly for the CCTs in the range of 4000k-6000k.

twisted_raven · 2019-04-05T14:10:28.000Z

There’s no right or wrong in it, it’s all just subjective. I think anywhere between 6000k and 4000k could be considered neutral-ish and appear white depending on how well your eyes are adjusted to the CCT at that time.

Direct midday sunlight is around 5500-5700k, while diffused daylight is around 6500k. Direct sunlight at mornings and evenings is more around 4-5000k.

In flashlights, I consider 5000k pretty damn neutral, anything 6000k or above cool white, and anything 4000k or under warm white.

Scallywag · 2019-04-05T14:17:44.000Z

In the interior lighting world, 2700K-3500K is "soft white", warmer is "warm white", ~4000K-4100K is "cool white", and 5000K+ is "daylight". This dates back to the CFL days, and is still used for the LED bulbs. Also 8000K-12000K for car headlights was called "blue" ;)

Around here, warm white is usually anything below 4000K. Neutral white is disupted territory, but usually 4000K-5000K (And typically not much cooler than 5000K at all). Cooler than that is cool white.

adam7027 · 2019-04-05T18:31:06.000Z

I would consider these:

up to 1500K: lava red
1500K to 2500K: (based on taste, any word with the meaning ‘very’ goes here…) warm white
2500K to 3300K: warm white
3300K to 4000K: soft white
4000K to 4500K: warm neutral white
4500K to 4800K: true neutral white
4800K to 5500K: cool neutral white
5500K to 6500K: cool white
6500K to 8000K: cold white
8000K to 10000K: (based on taste, any word with the meaning ‘very’ goes here…) cold white
10000K and upwards: sky blue

These titles are only suitable, if the examined light source has enough CRI (90, preferably 95+), otherwise, I would simplify the above:
4000K to 5000K is neutral white, and anything outside this is correspondingly warm/soft or cool/cold white.

Neutral white is a roughly determined condition, when all parts in the visible spectrum gets a proportionally close intensity to each other (for me, this also means, that I don’t like to call a below 75 CRI light neutral - especially for the already high deep blue spike, which is fairly common among those at 5000K).

I’d call high CRI cool white as pure white as well.

Also, daylight is a very vague title:
overcast day (sun covered by various thickness clouds) is 6000K to 8000K
clear sky is around 10000K or rather more
sunlight without air (e.g. viewed on the Moon) is 5700K,
midday sunlight with air on 0m above sea level is maybe around 4800K
late afternoon sunlight is mostly 3500-4000K-ish
sunset is not more than about 2200K