What is exactly neutral white ?

Is sunlight/daylight NW ?
I see beam shot of Quark AA2 NW and it is too yellow
Of several flash lights I owned (Cree XR-E, XP-E, Luxeon Rebel), the Rebel and a LED 6W desk light from Costco come closest to sunlight.

ktnguyen said:

Is sunlight/daylight NW ?
I see beam shot of Quark AA2 NW and it is too yellow
Of several flash lights I owned (Cree XR-E, XP-E, Luxeon Rebel), the Rebel and a LED 6W desk light from Costco come closest to sunlight.

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There seem to be many definitions of Neutral White - Some consider it to be sunlight color temperature, others consider it to be anything cooler than incans and warmer than sunlight, etc.

The best is to get the actual tint bin used in the light, i.e. a 5A tint is 4500K. Then you can compare it against other light sources, i.e. sunlight is ~5500-6000K, or a WC tint which is 6350K-7000K.

Personally I don't like dealing with terms like "Neutral" "Cool" or "Warm" - if you know the actual CCT, like "6000K", "3500K", "7000K" then you know exactly what you're dealing with.

But if it helps, Cree (the manufacturer of many LEDs) defines the following:

Cool White: 5000K-10000K
Outdoor White: 4300K-5300K

Cool White (ANSI): 5000K-8300K
Neutral White (ANSI): 3700K-5000K
Warm White (ANSI): 2600K-3700K

You can compare it to some other common light sources: http://en.wikipedia.org/wiki/Color_temperature

The important thing to understand about "neutral white" is that there is more yellow in the light. This is actually a good thing, because it increases contrast and therefore depth perception (particularly in outdoor environments with a lot of foliage) and shows the true colors of things better.

As a quick example of how this works, a few weeks ago my wife came home late with the kids from her mother's house and as I was helping them in, she got her Quark AA out that I bought her for Christmas last year and shined it up into the loquat tree in our front yard and said there was a raccoon in there. I looked up but couldn't see it even though the light was shining directly on it. I grabbed the NiteCore EZAAw (warm/neutral white) I keep on my keychain, cranked it up to high, and saw the raccoon instantly. The warmer tint of my light helped me see deeper into the branches of the tree, past all the leaves, to see the little bugger up there eating the fruit in our tree.

ktnguyen said:

What is exactly neutral white ?

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An opinion.

Theres a few good threads that show comparisons of the tint and it seems the neutral white looks much better. Will see if I can find some links to them.

Dim and yellow.

ktnguyen said:

What is exactly neutral white

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ktnguyen said:

Is sunlight/daylight NW ?
I see beam shot of Quark AA2 NW and it is too yellow
Of several flash lights I owned (Cree XR-E, XP-E, Luxeon Rebel), the Rebel and a LED 6W desk light from Costco come closest to sunlight.

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EVERYBODY PAY ATTENTION

Digital cameras are not eyes. Film cameras aren't, either. They have a setting for white balance (color temperature assumption to define 'white') that can dramatically change color of beamshots.

The ONLY thing a beamshot is good for is comparison between two lights (with the same distance to wall and identical exposure settings and color balance). The spill/hotspot size relationship shows up, but the relative brightness will be all wrong. Color, absolute brightness, and hotspot intensity will never look right on a camera. I can edit photos to try to make it look the way it looked to my eyes, but that's adding more complexity to try and hide the problem.

I like the CCT method:
cool neutral-white: 5000K
neutral neutral-white: 4500K
warm neutral-white: 4000K

cool warm-white: 3500K
neutral warm-white: 3000K
warm warm-white: 2500K

cool cool-white: 6500K
neutral cool-white: 6000K
warm cool-white: 5500K

glockboy said:

Dim and yellow.

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I think that would be more on the "Warm" side. The Warm does looks dim and yellow kinda like the battery is dying, I don't like the warm tints but the neutral white looks much brighter than that..

Watts Up! said:

I think that would be more on the "Warm" side. The Warm does looks dim and yellow kinda like the battery is dying, I don't like the warm tints but the neutral white looks much brighter than that..

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According to the info provided by 4Sevens about their neutral and warm lights, the neutral versions are reduced in flux by 7% and the warm by 28% over comparable cool tint emitters.

So yes, in terms of the physical intensity of the light they produce, yes, the are dimmer. However, the perceived differences are often less than that because the tints they give off are more appropriate for the wavelengths at which the cones in the retina are sensitive, creating a greater amount of activation (action potentials sent to the brain) and thus will typically appear brighter than for an equal lux of a cool tint.

As per my sig, I only buy neutral lights now, at least for my own personal use. It's not about brightness, it's about quality. Most modern LED lights are already bright enough that a reduction of 7% isn't noticeable.

XPG-R5-cool white, 139lm@350mA.
XPG-R4-neutral, 130lm@350mA.
6.5% difference is totally worth it. Those 9 lumens probably aren't even perceptible to the human eye.

Found this thread so you kinda see the difference.

http://jtice.com/review/lights/led_tints/

ktnguyen said:

Is sunlight/daylight NW ?
I see beam shot of Quark AA2 NW and it is too yellow
Of several flash lights I owned (Cree XR-E, XP-E, Luxeon Rebel), the Rebel and a LED 6W desk light from Costco come closest to sunlight.

Click to expand...

I think its a personal thing.

I have a quark nw and *personally* don't see it as "neutral", I see it as being quite warm and yellowish. Its nice to read in the dark with, but I find that I prefer cool whites (eg. normal quark, or fenix ld20 r5) and can actually see better with them outside. I feel I get a better idea of what colour something really is with the cool whites - I can tell something white is white, whereas with the neutral white, everything white looks dirty or yellow and I'm not sure if I'm looking at something yellow or should it be white. Makes bathroom look yuck at night!

I don't think you'll know until you try and compare in real life yourself. Then just go with whatever *you* like.

It also helps to remember that the surface reflectivity of the objects in your environment will affect your perception of whether a warmer of cooler color temperature is more useful. Urban environments tend to have numerous objects with higher surface reflectivity than woodland environments. (We all know that tree bark just doesn't reflect as much light as a sidewalk.) Urban environments therefore tend to be better illuminated by higher color temp lights, because the combination of light and surface reflectivity produces better edge definition and object recognition. In woodland environments the opposite is true: warmer color temps reflect better off of the darker surfaces typically found in nature (tree bark, leaves, dirt, rocks, etc.). This isn't a hard and fast rule, rather it is intended merely to spark an awareness of the fact that what you're seeing is reflected light, and that the surface characteristics of the objects being illuminated play a bigger role in our color perception than is generally acknowledged.

Warm White is roughly equivalent to typical indoor artificial light.
Neutral White is fairly close to noon sunlight.
Cool White is about a match for an overcast day.

If I pick one color and give myself five minutes to adjust, they all look perfectly white in the absence of another light source. Warm white is great walking in a wooded area, and cool white is very pleasant when you're using a light in the middle of the day to work on your plumbing or probe the depths of your engine bay. I'm really a fan of neutrals, though. With any combination of tints side-by-side, the neutral always looks white to me, with the others being too blue or yellow.

On top of that, when I first turn on a warm or cool light, about half the time the color will feel wrong at first, until I get used to it. I've never turned a neutral on and felt the tint was wrong in any way; it always looks just perfect. It's somewhat personal preference and somewhat depends on your usage, but I personally find 4000-4500 Kelvin to be ideal.

There may be a color temperature definition of "neutral," but I'm sure real world opinions will differ. I suspect those of us who grew up using incandescent lights will consider "neutral" to be warmer than those who are more used to the blues of older LED's.

I'm still using my L2D that has a P4 as my main flashlight. It has been on many bike rides, used around the house, taken on hiking trips, etc. over the years. Its beam is too blue/cold, particularly outdoors.

Warmer options weren't available back then. The next light I buy must have a neutral/warmer, more outdoor-friendly tint. It's sad when an old 2D Maglite with tired batteries lets you see things outdoors that a fancy purplish brighter light can't, and I've had that happen several times. Quality matters more than quantity.

flyingbrass said:

There may be a color temperature definition of "neutral," but I'm sure real world opinions will differ. I suspect those of us who grew up using incandescent lights will consider "neutral" to be warmer than those who are more used to the blues of older LED's.

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I don't think this is the case. The terms "cool white," "neutral white," and "warm white" have specific meanings defined by the American National Standards Institute. Just because someone used to LEDs may be more comfortable with a cool white, or someone coming from incandescents may be more comfortable with a warm white, does not make those colors "neutral" for that person.

aramid said:

I don't think this is the case. The terms "cool white," "neutral white," and "warm white" have specific meanings defined by the American National Standards Institute. Just because someone used to LEDs may be more comfortable with a cool white, or someone coming from incandescents may be more comfortable with a warm white, does not make those colors "neutral" for that person.

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I completely agree.

I'm not entirely sure why so many subjective opinions are entering this thread - as it seems to me the question is regarding the definition of terms??

I already posted the ANSI definitions in my prior post (#2)

hoongern said:

I completely agree.

I'm not entirely sure why so many subjective opinions are entering this thread - as it seems to me the question is regarding the definition of terms??

I already posted the ANSI definitions in my prior post (#2)

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There is a LOT of subjectivity to it. Just because there's been an ANSI definition doesn't mean that different people aren't going to see the light (no pun intended) in the same way.

This boils down to the fact there is a difference between the physical characteristics of the stimulus and the psychological/perceptual correlate produced in the brain and visual system.

Different people are different and have different make-ups for their eyes. Not everyone has the same proportions of the 3 cones types; some have more red ones, or blue ones, etc. and it creates subtle but significant differences in our perceptions.

The brain also adapts to consistent changes in the color make-up of the light we see. Ever notice how red or blue objects still look red or blue even when seen under a yellow or green light? This is because as long as the amount of green light coming off of each object is consistent, the visual system adapts and only sees the differences in color between those objects. This is how the visual system works (and indeed all our sensory-perceptual systems work), by looking for the differences in the stimuli received rather than the absolute characteristics of the stimulus. Thus we see the brighter of two lights as "a little brighter" or "a lot brighter", rather than "5 lumens brighter" or "50 lumens brighter". So even if a "neutral" light doesn't meet the specific ANSI definition, it will be perceived as more or less "white" in comparison to a cool tint simply because of how the neurons in the visual system are wired.

hrm.. does the ANSI definition include CRI?

CCT isn't the only determining factor of how the light "looks".