What colour temperature is subjectively closest to "pure white"?

[thedoc007]

Re: What colour temperature is subjectively "pure white"?

Subjectively, I much prefer cooler tints. Anything below 5000k looks off to me...a white sheet of paper doesn't look white any more, it is that simple. I don't care how it "feels", I just want white to look white. As phrased, it is a silly question (though it has generated some interesting comments), because to know what the subjective "pure white" color is, all you have to do is some testing on your own. No one else can tell you what your preference will be, or what color temperature you will perceive as "pure white". For me, 5500-6500k is ideal. I originally bought into the idea that it wasn't good for home lighting, but after buying several different color bulbs, and trying them out, I have changed my mind. My ideal setup is similar to how saabluster designed the Rev Captor...a couple bright 6500k bulbs, and one dimmer 3700k bulb to boost the CRI.

 

[TEEJ]

There is no "color" label that is actually meaningful other than as a range.

What we CALL red, or blue or green, etc, is simply a concept, not an exact value.

For example, real colors are actually infinitely varied, and the wavelength rather than the "temperature" would be a more accurate way to describe what we CALL "color".

There are a range of wavelengths that we might consider to be be "red" for example. Which is the "real red"?

They ALL are, but, based upon our societal influences, each of us will CONSIDER a particular wavelength RANGE to be "the most red", etc.


For example, we might look at a color, and describe it as sort of a yellowish green. Why do we not have a NAME for that color, the way we have for yellow, or green? Its because we just happened to name only a few colors, and could have just as easily labelled yellowish green as yellow, or green, or blue, or ishcabible, etc.

In Greek times for example, violet was how they described some people's hair, as they had fewer names for colors, so, black hair was called violet. This makes sense, as when you look at a color chart, violet DOES tail off to what we might call black....but they didn't have black as a color label yet...it was violet. IE: Black was violet. If we asked "what's the "true violet", what would they have said? The color of a Greek maiden's hair?







We have arbitrarily labeled part of the spectrum as being "a color". We even talk about "how many colors" are in a rainbow, etc. ALL the colors are in a rainbow, but, we artificially made up "break points" that divide the infinite number of colors into groups.

These groups do not actually exist in any physical sense of the word, other than by human consensus...and, different groups of humans have broken them down differently, so there are "colors" that people from different regions, etc, can argue about.....but, its all about the labels they each ascribed to parts of the spectrum.

To FURTHER attempt to use a color TEMPERATURE scale to describe a COLOR is going to be even more vague, as its not really about color as much as about the color at a particular time of the day for instance.


IE: There is no "color temperature" that = "pure white".

 

[markr6]

Re: What colour temperature is subjectively "pure white"?

I like the displays at home depot. I think they use CFLs which I don't use, but still gives you a good general idea.

 

[AnAppleSnail]

Yes, but that's just the sensory contrast of going from one situation to another. If you stick in one enviroment, then there should be a colour temperature that's closest to what most people would consider pure white (as you imply yourself afterwards).

Millennia of experience deny a constant environment. Sunlight ranges from 3000 to 7000K CCT, depending on conditions (Sunset, overcast, noonday, etc). You're looking for something that's not possible.

Look for a light source between 3000K and 5000K (Higher CCT for work-like tasks, lower for relaxing tasks), with good color perception card results. R9 is a weak point for LEDs and arc lamps - It's a delicious red. The blues are weak for hot filaments.

 

[SemiMan]

Lots of conjecture on this thread but the LRC did a study and found within the study group that almost without exception people picked 4000k as white +/- a few hundred k after adaptation.

 

[ElectronGuru]

I did my own study and found it to be 4300, within the range above:

http://www.candlepowerforums.com/vb/showthread.php?232038-Flashlight-Tint-Color-Reference

 

[fyrstormer]

4300K is significantly warmer than pure white to my eyes. 6000K is pure white to me, but I prefer 5000K because I like just a teensy bit more yellow in my light.

 

[recDNA]

4300K is significantly warmer than pure white to my eyes. 6000K is pure white to me, but I prefer 5000K because I like just a teensy bit more yellow in my light.

That's my preference as well. I don't enjoy brownish yellow light. Some people clearly do. Ideally you want a complete spectrum but led's cannot do that as I understand it. One thing I know. I find greenish light intolerable but I'm told some hunters prefer it.

 

[SemiMan]

The study was not about preference but about what light when dark adapted looked most "white".

In terms of preference under the black body ... Was the preferred color point at all CCTs in another study.

 

[markr6]

4300K is significantly warmer than pure white to my eyes. 6000K is pure white to me, but I prefer 5000K because I like just a teensy bit more yellow in my light.

Can't believe what I'm hearing?!?! :hairpull: It's amazing how different everyone is on this subject. Also can't believe peoples eyes can be so different from another.

But consider just my own eyes. When look out of just my left eye, it's like looking thru a warming filter. Just my right eye is like cooling filter. Very strange. This is more apparent when outside looking at landscapes, trees, sky, the road, etc. The difference is even more exaggeated with sunglasses on.

 

[Bullzeyebill]

Have you considered a cataract issue with one eye? I recently had cataract surgery on L eye, and now everything is brighter.

Bill

 

[fyrstormer]

Can't believe what I'm hearing?!?! :hairpull: It's amazing how different everyone is on this subject. Also can't believe peoples eyes can be so different from another.

But consider just my own eyes. When look out of just my left eye, it's like looking thru a warming filter. Just my right eye is like cooling filter. Very strange. This is more apparent when outside looking at landscapes, trees, sky, the road, etc. The difference is even more exaggeated with sunglasses on.

Oh, but they are. Everyone's retinas have different densities of red, green, and blue cones, and everyone's brains are more or less sensitive to inputs on those three channels. Some women have four-color vision, too, because they have two types of green cones, each one coded-for on one of their two X chromosomes.

 

[SemiMan]

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[markr6]

Have you considered a cataract issue with one eye? I recently had cataract surgery on L eye, and now everything is brighter.

Bill

No, but I did have a thorough exam just 2 weeks ago and everything was fine. I vaguely remember doing the standard test optomologists do when I was a kid, looking thru a book with "hidden" numbers in various colors. I think he said there was a very slight issue distinguishing certain colors, but haven't had a problem. Could have something to do with color temperatures...who knows.

 

[KITROBASKIN]

Re: What colour temperature is subjectively "pure white"?

Thanks to felixnauta for bringing this thread to the present.

The word 'subjective' allows some flexibility here. I used to consider the white-is-white standard to be the be-all-end-all of tint preference. Now I use another subjective metric:

Going outside when the light of the sun has the most pleasing cast (for me it is about 1/2 to 1 1/2 hours after sunrise) and finding an area of exposed dirt on the ground that is in partial shade (but one can also use the shadow made from your body). Now, shine your lights on the shadowed part of the dirt near dirt that is lit by the sun. Green plants and other objects don't look quite so 'off' as the medium brown dirt we have here, under the light of a flashlight.

Cool white looks washed out and dull. Warm white and 'neutral' XML2's look yellow. The SkyLumen SL-1 XML2 dedomed neutral looks kind of bluish green. The ZebraLight SC62d is close to the sun's tint but a little grey with maybe a tiny smidge of green. What looks the closest to early morning sun? For me it is the MBI HF Nichia 219A.

At night, it is the dirt around where I live that is the most distractingly off color under the light of a flashlight, and the Nichia makes the dirt look darker and 'richer'. But the sunlight test really shows how nice the Nichia is. I'm wondering how the 219B ~5000K looks?

 

[markr6]

Re: What colour temperature is subjectively "pure white"?

I'm wondering how the 219B ~5000K looks?

I like the 219B in my L10C. It's on the cool side though. While I think it makes colors more accurate, I prefer the warmness (slight red tint) of the 219A. And I would say the 218B is pretty close to the SC62d.

 

[fyrstormer]

Yet anytime testing is done except for the obvious outliers most people test surprisingly similar.

If you really believe that, you need to look up the definition of "confirmation bias". Even scientists are susceptible to it, but when common people like us get our hands on the data, confirmation bias basically bulldozes anything resembling an accurate interpretation of the data. I don't know how many times I've seen someone start a thread on CPF about an article that "proves" their own personal preference is the default for humanity, whether it's warm-tinted white light or red night-vision light or whatever. The arguments ALWAYS go something like this: "I just read an article stating that humans are 'programmed'/'adapted'/'designed' to prefer a certain type of light. Don't argue with me, it's totally true! Look, I have numbers! Do you have numbers? No? Well, that proves my preference is based on fact and other people's preferences are based on opinions." Arguments like that aren't even logical enough to be wrong.

Thank you and goodnight.

 

[SemiMan]

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[thedoc007]

Scientific studies can only result in confirmation bias if the outcome is one that is generally known or accepted. That absolutely is not the case in this study.

People also like to keep believing what they believe even proven not true.

The study was not about what color you like it was is this color white. If not , how do you think it differs from white. Given that people would not even know what CCT they were being shown how could they have confirmation bias? Without relative comparison or references it hard to pick CCT ... You just know whether it looks sort of reddish yellow, too bluish, or WHITE ... Exactly what the study was trying to figure out .. Where was that point.


Of course another thing that happens is people bash studies or jump on the study bandwagon without reading them and understanding them.

The whole idea of a study to figure out what is "subjectively" pure white is a joke. Even if most people think it is 4300k (I haven't read the study and can't say either way) that doesn't really mean anything. It isn't like someone else's opinion is a predictor of your own opinion...you can't generalize to a population at all, since it is by definition an individual perception. If you want to know what is subjectively pure white, just announcing your own opinion has exactly the same scientific value, i.e., none.

 

[SemiMan]

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