Need for warm vs. cool tint LEDs?

[burntoshine]

I like the warmer high cri tints the best. They are really close to the tint of incandescent lights, which I personally think is pretty dang neat. It's the best both worlds; you get the warm & cozy, better-color-rendering tint with awesome efficiency.

For me, it's the need of not having a harsh "ghost-vision" blue light. I have neutrals and warms, but no cools. I had bought only cool white lights for years until one day I bought a Liteflux LF2XT, which were primarily available in neutral tints. That was the beginning of the end of cool tints for me.

It would be great if there was a little tint kit one could buy. A flashlight or similar unit that would be inexpensive, which ran on one AA and had three or four or five LEDs, all with different tints (standard cool, standard neutral, neutral high cri, warm high cri, etcetera) that you could switch between. Its sole purpose would be to let the user discover which tint is best for them and their uses. You can look at beam shots all day on tha net, but you need real-world experience to really get to know a tint.

 

[Gerardn3]

Interesting. That makes sense, as I do tend to prefer warmer tints at lower illumination levels. And, I find that CRI is less important when I have my light turned up high, because colors are easier to tell apart at high illumination even if the CRI isn't great.

That sounds reasonable, considering the eye has more difficulty telling colors apart in dim light even with a "perfect" light source.

Personally, I find that the Kruithof curve seems to correlate well to my own experience. I see things more clearly an interpret colors more accurately if the color temperature correlates to the brightness of the light, and it's just easier on eyes and brain. Some people have mentioned cases in which a particular light source doesn't even allow them to distinguish certain objects or colors, but even if it's not that extreme, the most "natural" light source can still make any activity easier. It can be hard to draw the line between preference and actual usefulness, but in my case the two seem to go hand in hand.

 

[Swedpat]

For sure; there are several aspects in this matter. The eye perception sometimes can be misleading, and different persons perceptions are different.
I have heard a few people telling me that they prefer cooler tint because it works better for them, while I experience the opposite.
The eye's ability to accustom to different tints also is impressive.
A very cool tint can alone be perceived as the whitest of white but compared to a warmer tint it instantly looks bluish. I noticed even a neutral tint I sometimes imagine as slightly bluish compared to a very warm light source. And that despite I was so convinced that it is absolutely NOTHING close to bluish...
Consequently: I can accustom to a cool tint if I need to even if I prefer a neutral. But when I compare a cool white to a neutral and change from the neutral to the cool I just experience the cool so unpleasant and really want the neutral instead.

 

[Etsu]

I find objects under cool white appear sharper than under warm white. Probably just an illusion, like some people find cool white decreases depth perception (I don't experience that).

 

[Gerardn3]

It would be great if there was a little tint kit one could buy. A flashlight or similar unit that would be inexpensive, which ran on one AA and had three or four or five LEDs, all with different tints (standard cool, standard neutral, neutral high cri, warm high cri, etcetera) that you could switch between. Its sole purpose would be to let the user discover which tint is best for them and their uses. You can look at beam shots all day on tha net, but you need real-world experience to really get to know a tint.

That makes me think of the Philips Hue lamps that allow for extensive color temperature and tint adjustment using multiple LEDs. I'd love to see that concept become more widespread, and there's certainly potential for similar concepts to be implemented in flashlights.

For sure; there are several aspects in this matter. The eye perception sometimes can be misleading, and different persons perceptions are different.
I have heard a few people telling me that they prefer cooler tint because it works better for them, while I experience the opposite.
The eye's ability to accustom to different tints also is impressive.
A very cool tint can alone be perceived as the whitest of white but compared to a warmer tint it instantly looks bluish. I noticed even a neutral tint I sometimes imagine as slightly bluish compared to a very warm light source. And that despite I was so convinced that it is absolutely NOTHING close to bluish...
Consequently: I can accustom to a cool tint if I need to even if I prefer a neutral. But when I compare a cool white to a neutral and change from the neutral to the cool I just experience the cool so unpleasant and really want the neutral instead.

The eyes/brain do have an impressive ability to adapt to various color temperatures. One thing I noticed about the Kruithof curve is that it shows that people tend to adapt better to a wider range of color temperature at high brightness levels, while the ideal range is narrow for low brightness levels. That could mean it's easier to adjust to various warm/neutral/cool flashlights when using a high brightness beam, but color temperature may become more important if you are using a low brightness level or trying to light up a room with ambient lighting.

 

[18650]

When it comes to flashlights, one might perceive the tint differently depending on the intensity of the beam. It might seem more natural for a low intensity beam to have a lower color temperature, and a high intensity beam to have a higher color temperature. One thing I noticed about LED flashlights is that what is considered "neutral" (often 4500-5500K) is generally much higher in color temperature than it is for residential and commercial lighting. When it comes to fluorescent lighting, it's usually something like 3000K = warm, 3500K = neutral, 4100K = cool, 5000-6500K = daylight. My guess is that this is because a high intensity flashlight beam looks more neutral to most people when the color temperature is higher compared to a less intense ambient light filling a room. With multi-mode LED flashlights, you might even find that that the light looks more natural at one brightness level versus another.

Offices I have been in vary from 3500K-5000K and everything in between. Big box store lighting seems to tend towards the 5000K range and above. FWIW the "neutral" fluorescent white balance setting on my camera is set at 5000K and "daylight" level is set at 6500K.

 

[wvdavidr]

I have two "neutral white" lights: Eagletac SX25L3 w/MT-G and a G25C2 MK II. This is purely subjective, but I think they're easier on my eyes. I am fine with the Olight M22 vs. the Mk II, but, well, the Mk II is more pleasant for me to use. I also find those Eags better outside, where brown and green colors look more natural. Now, if Fenix could make a TK75 with neutral white... !

 

[Raygun V]

I work for a design firm and I am just used to color accuracy. I can't stand the look of a blue light, or bluish light...nothing looks the way it does under the sun. I have been calibrating TV's and monitors for a couple decades and nothing drives me more batty than a cool color setting.

I am sure cool lights have their uses, but I have not come across the in my life yet.

 

[leon2245]

I work for a design firm and I am just used to color accuracy. I can't stand the look of a blue light, or bluish light...nothing looks the way it does under the sun. I have been calibrating TV's and monitors for a couple decades and nothing drives me more batty than a cool color setting.
I am sure cool lights have their uses, but I have not come across the in my life yet.

Where white = 6500k right?

 

[MichaelW]

Where does warm stop and neutral start?

I like that Lumileds shows the SPD of each CCT versus the three generic distributions that Cree offers in their documentation. See page 10 DS107.pdf
Since it is a normalized output [I with they would produce a non-normalized output, eh just for fun. So we can see exactly how much more efficient a 5000K cool is. 5% more than 4500, 10% than 4000, 15% than 3500, 20% than 3000, 25% than 2700], there really isn't any loss of 600nm performance in increasing the CCT from 2700-3000-3500-4000. So the name of the game is mid-range. Pick your 500-600nm output.

At what CCT is the peak wavelength of the blue pump, and the phosphor 'hump' the same? Something between 3500 & 4000K. Is there anything special about that CCT? Can the boundary between warm & neutral be defined as the point where there are two equal spectral maxima.

Older people need cooler lights to offset the age/experience yellowing of the eyes. Understandable. Just don't package a 5000K light and tell me it is neutral. It has its place, in the urban setting.

 

[inetdog]

Re: Where does warm stop and neutral start?

Older people need cooler lights to offset the age/experience yellowing of the eyes. Understandable. Just don't package a 5000K light and tell me it is neutral. It has its place, in the urban setting.

They look out of place next to campfire by the chuckwagon?

The CCT of moonlight is pretty high too, but not bright enough for good color recognition.

Tapatalk!

 

[Swedpat]

For people interested in tint/color temperature, it might be worthwhile to do a search for the "Kruithof curve". It has been found that people tend to perceive different color temperatures differently depending on the brightness/intensity of the light. Generally, higher color temperatures are preferred for brighter light, and lower color temperatures are preferred for dimmer light. That can play a huge factor in what seems most natural or neutral in varying circumstances. Sunlight is on the high side of color temperature, but seems natural because it is very bright. People tend to prefer "warm" lighting (2700-3000K) for home use, because it is generally very dim comparatively. For things like offices, stores, etc. lighting tends to be somewhere in between in the 3500-4100K range because people find it more natural for those medium brightness levels.

When it comes to flashlights, one might perceive the tint differently depending on the intensity of the beam. It might seem more natural for a low intensity beam to have a lower color temperature, and a high intensity beam to have a higher color temperature. One thing I noticed about LED flashlights is that what is considered "neutral" (often 4500-5500K) is generally much higher in color temperature than it is for residential and commercial lighting. When it comes to fluorescent lighting, it's usually something like 3000K = warm, 3500K = neutral, 4100K = cool, 5000-6500K = daylight. My guess is that this is because a high intensity flashlight beam looks more neutral to most people when the color temperature is higher compared to a less intense ambient light filling a room. With multi-mode LED flashlights, you might even find that that the light looks more natural at one brightness level versus another.

Also, light sources such as LED and fluorescent don't really have a "color temperature" in the way that the sun or an incandescent light source does. They are specified with a "correlated color temperature" (CCT) which is basically just what the light gets closest to when compared to an actual incandescent source, but the tint and spectrum can still vary significantly even for two lamps with the same CCT. The CRI specification helps to describe how well the light source renders different colors, but even with the same CCT *and* CRI specified, there can be noticeable variations in the exact tint and spectrum.

Of course it's still going to come down to personal preference/usage in the end. Experimenting with different color temperatures and tints at least provides another excuse to play with more flashlights.

That sounds reasonable, considering the eye has more difficulty telling colors apart in dim light even with a "perfect" light source.

Personally, I find that the Kruithof curve seems to correlate well to my own experience. I see things more clearly an interpret colors more accurately if the color temperature correlates to the brightness of the light, and it's just easier on eyes and brain. Some people have mentioned cases in which a particular light source doesn't even allow them to distinguish certain objects or colors, but even if it's not that extreme, the most "natural" light source can still make any activity easier. It can be hard to draw the line between preference and actual usefulness, but in my case the two seem to go hand in hand.

This is interesting. Actually I thought that at low brightness it's more difficult to see with warm tint. However, I have to say that a very bright warm light is beautiful. I think Malkoff M91W is 3700K or so, and it's like turning on a bright incandescent light bulb.
But I noticed that while warm tint is very nice at high brightness it can be perceived as boring yellowish at low brightness. Is it only because that I perceive the tint different at different intensities? I know that an LED doesn't change the color temperature like an incandescent, but there is a slight change.

 

[Etsu]

This is interesting. Actually I thought that at low brightness it's more difficult to see with warm tint.

Kind of. Once you get down to very low light levels, and you're just using the rods in your eyes (not the cones that are used for bright light and color), the rods are most sensitive to blue-green wavelengths of light. So, a cool-white light would probably be better at activating those rods at very low illumination (more blue-green wavelengths in cool-white than in a warm tint). Rods don't see color, though, so you won't notice any "blue-green".

 

[bbb74]

Was going to start my own thread but hopefully its ok to necro this one???

To start with I think each individual's preferred tint is a combination of psychology (what you grew up with or are used to at home etc), physiology (different people see colours somewhat differently - old eyes are different to young eyes), the conditions under which you use the light, and personal preference.

I like neutral white for general lighting inside a tent or when camping, or when dealing with food.

I find it looks too dirty if i'm looking at white bathroom fittings (!) when sneaking around when the rest of the family is asleep, or outside when hiking at night in my area. There are a lot of browns and muted greens where I live and I find a cool white actually helps differentiate things better than a neutral. Also the really weird thing is, when I'm on my own in the middle of the bush in the middle of nowhere, the nw's freak me out, I have no idea why!!!

That's because our eyes are designed to detect contrast in colors, not to detect actual colors.

For example, if a light source is composed of 2 distinct colors, a monochromatic blue light and a monochromatic yellow light, we see that as green. It's NOT green! It's actually 2 separate colors. But our eyes (and brains) are designed to mush them together so we just see one color. We don't even see either of the true colors of the light!

For an analogy, if I were to play a musical chord on a piano, you'd hear every note in that chord. But if your hearing was as bad with sound waves as our eyes are with light waves, then you'd just hear a single note somewhere between the low and high note of the chord. You'd basically be tone-deaf. That's what are sight is: tone-deaf!

If that wasn't bad enough, it gets worse when our eyes combine low-frequency light (red) and high-frequency light (blue). That comes out purple. But we also tend to see very high frequency light (violet) as a kind of purple as well. Somehow, we perceive violet completely wrong! Probably because our only photo receptors are for blue, green, and red. Violet triggers both blue and red, which is messed up.

If we were able to see and distinguish color the way it really is, the world would look completely different.

The number of times I've tried to explain this to people and failed. Your chord analogy is excellent thankyou!!!!!!!!

 

[jon_slider]

At night and in low light, I prefer warm tint
During the day and in bright light, I prefer cool tint
So I carry one of each, so I can change my mind.

The following quotes really helped me understand my preferences better, thanks for reviving the thread.

I think most people agree tint is a personal preference. However, I think its actually not so personal, it has more to do with how bright the setting is in which the light is being used. I change my mind every morning which tint is my favorite. During a dark night I like 3000k and need less lumens, during a bright day I prefer 6000k and need more lumens.

Kruithof curve. It has been found that people tend to perceive different color temperatures differently depending on the brightness/intensity of the light. Generally, higher color temperatures are preferred for brighter light, and lower color temperatures are preferred for dimmer light.

Interesting. That makes sense, as I do tend to prefer warmer tints at lower illumination levels. And, I find that CRI is less important when I have my light turned up high, because colors are easier to tell apart at high illumination even if the CRI isn't great.

in the following Kruithof curve I added lines at 300 Lux and 10,000 lux in the Pleasant range.
note that
at 300 Lux, 3000k is Pleasant (not too red), and 6000k seems too blue at that low Lux
at 10,000 lux, 3000k is too red and 6000k is Pleasant, not too blue, at that high Lux.

 

[markr6]

5000K at any level for me :rock:

 

[jon_slider]

5000K at any level for me :rock:

lets explore if there is a pattern in your usage preference

Is your usage pattern primarily high brightness, above 2000Lux, (above 100 lumens)?

Do you not mind the blue tint of a 5000k light at 100Lux because you dont use low lumen levels (below 20 lumens) most of the time?

Imo the Nichia 219 @4500k is a really nice tint. Its still a compromise, too rose colored in bright settings, and too blue in dim settings, but imo an excellent compromise between CRI and brightness.

I think we all agree its good to have choices for different applications

 

[markr6]

lets explore if there is a pattern in your usage preference

Is your usage pattern primarily high brightness, above 2000Lux, (above 100 lumens)?

Do you not mind the blue tint of a 5000k light at 100Lux because you dont use low lumen levels (below 20 lumens) most of the time?

Imo the Nichia 219 @4500k is a really nice tint. Its still a compromise, too rose colored in bright settings, and too blue in dim settings, but imo an excellent compromise between CRI and brightness.

I think we all agree its good to have choices for different applications

4500K is fine. But I'll take 5000K at any level. I've been using my EC4SW a lot (2-2000lm) and I'm more than satisfied with it. Sorry that's not very specific, but it's that good I don't really care about the application. Sure there may be a preference for some applications, but I find the 5000K a good all-around temp.

 

[jhe888]

I think people are used to warmer colored light, and many just like it better because it is what we are used to. It shows colors in the same relationships to each other that we are used to and we can better judge color that way.

Most artificial light is warmer in tone. Natural sunlight is warmer in the mornings and evenings, and is neutral only in the middle of the day. Sunlight is only on the cooler side under certain conditions.

It is purely a matter of preference, but that is my theory as to why many prefer a slightly warmer tint to a cooler one.

 

[twistedraven]

My experiences don't echo that chart at all. Most any led I've tried shows its tint shifts more at lower lux levels than when at brighter luminance. For example, the N219B shows its rosy tint more, the XML2 easywhite on my Zebralight shows its yellow tint more, the XHP35 I have shows its green tint more, the XPL-HI in my Predator shows its blue tint more. The higher the brightness is on any of these lights, and the closer to a neutral white they approach.

To use the XML2 easywhite @5000k specifically while we're on topic, it appears warmer and more yellow the lower brightness it is, and gets cooler the higher brightness it is(albeit still not on the cooler side of white.)