Some thoughts on colour perception

I just got hold of my first R2 light - a Solarforce L2, with the R2 emitter.

I'm really pleased with it: really bright, good smooth beam, tons of throw, and - best of all - a superb crisp, clean pure white.

As soon as I switched it on though, my missus said: "ooo, that looks really blue !"

To me there's not a hint of blue - just what I'd describe as a pure 'ice-white'.

Which got me thinking about all of the debate on here at the moment about tints and 'cool' vs. 'warm'. Some of this of course is bound to be personal preference which is fair enough, but I just wonder to what extent there is a variation in how people perceive the colours ?

I'm not talking about gross effects like colour-blindness, but whether there are much subtler variations in the way that people see different tints in the colours.

I can imagine that someone who sees the beam as blue wouldn't like this light so much, and would probably prefer a 'warmer' colour. To me, a lot of the other cree lights look yellowy/greeny :green: and I'd rather have what I perceive as a pure white.

I prefer daylight (6500K) as well for all indoor lighting except mood lighting. I had some CFLs of this type burning where I was working and this girl said something like "That light is really blue!!". To me it just looks pure white. But I suppose to someone used to 2700K all their lives, 6500 would be perceived as bluer than it really is, especially at lower light levels.

To me, a bunch of these CFLs burn with a greenish tint. (a notable exception would be the GE line, which seems to have a better white balance than many brands.) Similar to WG crees- compared to 6000K sunlight at the same intensity, some look quite greenish. But you get used to that tint if its the only light you're looking at. And it does do a better job rendering green plants...

Now daylight CFLs are becoming quite easy to find in stores, so maybe this perception will start shifting?

I have no doubt that people perceive color(s) differently. I also have no doubt that what color/tint pleases one person need not please any other, and what one person finds unpleasant another may find highly attractive.

I used to be into the "pure white" LEDs and trumpeted how much I liked them better than incandescents. However, that was before I saw the 5A Q3. In real world use, the warm tint makes things outdoors look much more "natural," and the typical "pure white" tints now make me feel almost queasy. If and when 5A reaches the R2 bin, I will be happy as can be.

Now, I am sure that if I showed my CL1H with 5A Q3 or warm K2 to enough people, at least one of them would say it appears yellow, or orange, or "hot." But that's okay. However, I don't pretend that my preference for the warmer tints is anything more than one man's peculiar set of affections. :thumbsup:

Color exists in one place and one place alone, inside the mind. Since there is a problem of epistomological access to the contents of another's mind, we can never know exactly how they perceive the world, nor how we perceive the world in relation to them. My outlook for the future is that LED manufacturer's will continue to work on improving efficiency, but the next major area of improvement will be not to perfect "the perfect tint," but to provide a wide enough variety that people can choose what makes them happy.

I have a red green difficiency but also have problems with shades of colours. I'm sure a light I see as warm would be warmer to someone else. Likewise with cooler colours. A cool bluish light to my eyes may be more purple to someone else.

Perception is relative. Depends on the ambient lighting, and also any secondary lighting source you are directly comparing it against.

yes its HIGHLY subjective and there are no absolutes.

I generally prefer a yellow-ish tint. Cool white tends to hide surface textures of dirt, wood and foliage. Although I usually perceive pale whites as being brighter, when in reality they may not be. A slight green tint does not seem to impair my vision as much as others, as long as it has that hint of yellow (pic below). Yellow once again being the common preference.

I can detect PWM that others can't. I was standing at someone else desk and asked how they can stand their computer screen flickering like that and they had no idea what I was talking about.

I prefer the light of incandescents and hate those HID car lights, but obviously somebody must like them. I was in a mtn bike race once and somebody came up behind me with the 1st gen Cateye HID and I got an instant headache. I could also clearly see the pulse frequency.

My brother can hear really high pitch noises that I can't though.

Maybe a poll should be in order? Which do you like best?
I'm partial to:
Cy: .365
Cx: .34

For me, the important thing about warmer lights is their ability to be used for a sustained period of time without eye strain.

Analogy: I have a convertible car, and I love to have an aggressive exhaust note. After riding for a few hours in a friend's car with a loud exhaust, I got a headache! I decided to upgrade, but only to something slightly louder than stock.

LED lights (or flourescent lights) can be the same way. Too cold and my eyes get strained.

cave dave said:

I can detect PWM that others can't. I was standing at someone else desk and asked how they can stand their computer screen flickering like that and they had no idea what I was talking about.

I prefer the light of incandescents and hate those HID car lights, but obviously somebody must like them. I was in a mtn bike race once and somebody came up behind me with the 1st gen Cateye HID and I got an instant headache. I could also clearly see the pulse frequency.

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Same here, though I can also detect high-pitched noise such as CRT screen whine etc. I can detect the PWM on new Mercedes/BMW rear lights, which really annoys me when I'm following them on the road. You'd have thought a premium car like that would use a non-detectable frequency.

The closer to incandescent the better as far as I'm concerned - really don't like pure 'white' tints.

Moonshadow said:

As soon as I switched it on though, my missus said: "ooo, that looks really blue !"

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Put your wife in a room that has cool lighting for a few minutes, then show her the light.

I like pure white light, the whiter and more blinding the better. I simply cannot stand warm tint lights. Maybe its just me, but i can pick out colors and textures much better with pure white light than i can with warm puke color tints that everyone else seems so in love with. YMMV. sadly, i'm still searching for that perfect pure white tint, gonna buy a HID soon.

Bushman5 said:

I like pure white light, the whiter and more blinding the better. I simply cannot stand warm tint lights. Maybe its just me, but i can pick out colors and textures much better with pure white light than i can with warm puke color tints that everyone else seems so in love with. YMMV

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I don't know what warm tint lights you have been playing with but I have a McGizmo Sundrop (Nichia 083), a JetBeam Element E3P (Q3-5A) and 2008 Inova T1 (K2) and I would certainly not classify those as "warm puke color tints".

I did a quick google search and found this FAQ regarding color perception:

Munsell Color Science Laboratory - Perception FAQ

They did note that different individuals do have differences in color perception:

Do different people see the same color in different shades? Why?

While normal color vision (that is for observers who are not color blind) is very similar from person to person, there are differences large enough to be noticed. Most often this happens in color matching when one person sees two stimuli as a match and another does not. Simply put, these differences are caused by a number of physiological differences in the visual system (just like people are different in many other ways). Some of the causes are differences in the transmittance of the eye lens (which gets yellow with age and also varies from person to person), a protective yellow filter layer on top of our retinas, and the photoreceptor responses. In addition, there are also differences in the ways individuals assign names to various colors.

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One thing that seems to be an obvious cause of differences in color perception is aging.

How does aging affect color perception? Are older people able to discriminate brighter colors or softer colors better?

As we age, the lens in our eye begins to absorb and scatter more blue light (it becomes yellower). This causes a decrease in visual sensitivity to shorter wavelengths that make us less sensitive to blue colors and less able to discriminate purple and red colors. There also tends to be more of a negative effect of glare as we age. So really, no colors are discriminated better as people get older and whether brighter or softer colors are preferable would probably depend on the particular person and the illumination and viewing conditions.

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Another cause of variations in color perception seem to be due to gender:

What are the differences in perception of color by males and females?

The most significant difference is in terms of color blindness. Color blindness is a sex-linked genetic trait that is carried by women and normally expressed in men. So while about 8% of males have some form of color vision deficiency, there are almost no females with color vision deficiencies. There are a few other differences, but they seem to have little meaningful impact on perception. For example, it is possible for a woman to have 4 types of cone receptors instead of the "normal" three. However, there is no evidence that they make any special use of them. Their color vision is still trichromatic (3 dimensional) and the fourth type is very similar to one of the others anyway

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Get the coldest LED you have now get the elcheapo multi 5mm LED light you bought before you new better and compare them side by side notice how much nicer the cool LED looks now.

I'll sometimes pick up one of my P4 lights to use and think to myself how good the tint looks until I compare it to one of the Q3 5A LEDs I've been using lately. It seems that we all start off ignorant in any field of knowledge and then we learn what we like, think wine for instance the more educated you become the more particular you become.

There is a lot of personal taste involved as well whether it be LEDs or wine.

Norm

My first thought on colour perception is that I spell it color.

Unless your computer monitor is calibrated, the bin chart in message #7 by cave dave will vary from computer to computer. That's in addition to all the other variables discussed above. I have my monitors calibrated with a home theater tune up DVD. A lot cheaper than those $150-200 ones you can buy. Would be curious to know how close they really are.

One of the reasons for men/women ratio for colorblindness is that the red gene for red vision is only found on the X chromosome. Men only have 1 copy, women have 2. If the red gene is damaged for whatever reason (usually heredity) in a man then that results in him not being able to see that color. Women have 2 copies of the red gene. If one is damaged then the 2nd copy will be there and they can still see red. If both copies are good, then women may actually see red different than men. Maybe that's where the 4th cone comes from.

I'm 55yo. Can't take yellow lighting anymore. I swapped out all my 3500K CFL's for 4100K's. Much happier now. Can stand the daylight CFL's either. At this time of year here in Colorado the sun is very yellow compared to summer. Not happy about that, but not much I can do about it. lol. :shrug:

LuxLuthor said:

My first thought on colour perception is that I spell it color.

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What's your thoughts on coloured aluminium Lux
You may even realise that Moonshadow is right coming from very close to where the language originated, although I'm not too sure I'd trust a Scotsman when it comes to speaking English. :nana:
Norm

Norm said:

What's your thoughts on coloured aluminium Lux
You may even realise that Moonshadow is right coming from very close to where the language originated, although I'm not too sure I'd trust a Scotsman when it comes to speaking English. :nana:
Norm

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LOL! Well, honestly it freaks me out. I only trust a Scotsman for one thing. Knowing a good Scotch to drink.

Is it a "rule" that cooler tinted LEDs (all else being equal) will *always* shed more lumens than a warmer tinted LED, all else being equal?

No, the reason they do that right now is because the cooler tint phosphors are more efficient than the warm tint phosphors. Cree's latest lab LED has a color temp of around 4700K (well in the warm end of the camp, I think that would be around a 3a or 4a tint) and is over 160 lumens per watt.

My biggest pet peeve about these color perception discussions is that too many people look at and examine the color of the light, not the color of the objects in it. To me, cool color light looks nicest, whitest. But, objects and hence vision looks better with a warmer tint. I prefer around 4000K.