Is "white" overrated?

Is \"white\" overrated?

I've made some very non-scientific, purely subjective observations with all my LED lights. In comparing the color temperature of various lights, I found that my lights that have a slight yellow bias tend to throw the farthest. I'm not talking "puke" green LED, just a slight yellow tint. I'm wondering if a warmer color temperature has a better ability to penetrate through the dark. Ever wonder why fog lights are amber and not blue? My brightest, whitest light appears to be more reflected by particles in the air (dust) and hence the light it reflects back to me tends to obscure the light reflected back from the object I'm trying to illuminate. Does anyone share this observation, or am I going off the deep end staring into too many bright lights?

CM

Re: Is \"white\" overrated?

I don't know about yellow tinted LEDs, but I did just receive a couple of Arc LSL-P's seconds that have quite a purple tint. I was kinda bummed out until I took them outside and turned them on. I was very pleasantly suprised at their output. These are my first low domes, and I am quite impressed. I can certainly see a difference between these and my (very white and bright) LSH-P, but it isn't as big a difference as I thought it would be. /ubbthreads/images/graemlins/smile.gif Having a little color in there certainly seems to be easier on the eyes, at least my eyes. I think I saw somewhere that Pete G. said that your eyes percieve the colored light to be brighter too? White is very nice, but I do think it's overrated.

Peter

Re: Is \"white\" overrated?

[ QUOTE ]
CM said:
Ever wonder why fog lights are amber and not blue?

[/ QUOTE ]

Not really. As I understand it, two reasons: Light *bulbs* put out a lot of red/yellow light, very little blue (blue fog lights would be very dim, relatively), and blue light reflects badly off water (lakes look blue) so yellow will penetrate, not 'flash back'.

Doug Owen

Re: Is

I actually agree CM. My SNII is extremely bright when used close-up, but for throw, I find that the yellower lights like Surefire's actually are easier on the eyes and appear to make things more recognisable from a distance. I would get the Mag amber lens, but that would compromise the superior transmission of the UCL, and probably make it more yellow than I'd want it.

Re: Is

We used to use yellow shooting/driving glasses because yellow increased contrast in hasy or low light conditions and made it easier to spot targets in green leafy areas.

I would think that yellow light would do the same. Also, isn't yellow one of the colors the eye perceives as bright? Cyan being the other color.

Re: Is

What happened to the title of this thread?

Peter

Re: Is \"white\" overrated?

There, the title is back. Check out Quickbeam's explanation:

If I want a single color LED light, which is the best to see with?
(scroll down until you see the question above)

It describes that while white is best for color distinction, yellow takes advantage of our eyes more effectively, thus allowing us to see more with the light we have, which I assume means "brighter"?

Re: Is white overrated?

[ QUOTE ]
LitFuse said:
What happened to the title of this thread?

[/ QUOTE ]

It's the quotation marks in the title that causes it disappear. I removed them in this reply.

Re: Is white overrated?

Hello CM,

I don't know about being over rated, but I use to believe that white was the absence of all color.

Since finding CPF I have now come to realize that LED white lies between blue and green.

I am sure there is some hidden meaning in this, but I have yet to see the light...

Tom

Re: Is white overrated?

Actually, black is the absence of all color. True white is a mixture of all the basic colors.

Re: Is white overrated?

Hello Empath,

My son and I discussed this and thought we had it right. Oh well, it's just hard to get proper information from the younger generation...

He still disagree's with you. He says if you add all the basic colors together you get black. If you subtract all the colors out, you get white.

I'm sticking to my story, white is between blue and green.

Tom

Re: Is white overrated?

I thought that if you combined all the colors you get brown. Whenever I mix a bunch of paint colors I get a brrown in the end.

Re: Is white overrated?

white is every color.

that's how when you shine a flashlight at a prism, you get different colors.

Re: Is white overrated?

[ QUOTE ]
SilverFox said:
He still disagree's with you. He says if you add all the basic colors together you get black. If you subtract all the colors out, you get white.

[/ QUOTE ]

Both your son and Empath are right.

Huh?

Well, Empath is correct -
when you mix all the color lights togther you get white light.

Your son is also correct -
in the case of say mixing paints - if you mixed all the colors together you would get black.

Yellow/Amber light
I'm not an expert on this - but it seems that my eyes see better contrast and definition under yellow/amber light - not necessarily perceived as brighter - but I manage to see better under dimmer conditions with yellow/amber.

By sheer coincidence this article was linked in another thread:

http://www.speleogroup.org/lampTest2003.html

QUOTE:
The Red-Orange high-dome Star/O was the brightest of the lamps in the cave, but it did give an green-tinged after-image. Used on its own one became adjusted to the color, but in combination with other lamps it was distracting. Remarkable effects on digital cameras...

The Amber high-dome Star/O was easily the most acceptable of the monochrome lamps, presumably because the color is familiar (being almost the same as sodium street-lamps) and a reasonable match to the typical colors found in many caves.

The White Star/O was not as bright as the Red-Orange and AMber lamps, but was much better for seeing detail and color (for example, moon-milk and calcite in rocks). A slightly warmer white would have been preferred (by cavers used to incandescent lamps) and the sample we used gave an impression of a 'purple spot' in the central part of the beam. (This was less noticeable in smaller passages, where the lower power settings were found to be an advantage, too.)

The Cyan Star/O was the least liked of the four Star/O lamps. It's light, though quite bright, was hard to work with (though with some improvement after accomodation). Not recommended.
<snip>
White or Amber LEDs are the best colors (of those we tried) for the task. The extra brightness of the Cyan or Red-Orange LEDs did not compensate for the distraction effect.
UNQUOTE

Re: Is white overrated?

Pi, there is a difference between reflective and transmissive colors.

In reflective colors (the light originates elsewhere and is reflected by something of some coloror in other words the object absorbs all but it's color) if you add all those colors (like one would with paint) you do often end up with a blah brown (should be black).

With transmissive colors, where the light source is colored (on it's own, or via a filter or prism, or whatever) if you add all those light sources you get white.

Transmissive colorwheel is generally RGB, reflective color wheel is generally RYB. Transmissively, you get yellow by adding red and green, reflectively, you get green by adding yellow and blue.

Totally different. /ubbthreads/images/graemlins/grin.gif

Re: Is white overrated?

Spectrally, white is very broad. So for color rendition, white is what you want. However, though my "white" leds appear very bright close range, they can't match the throw, at least perception-wise, of my yellow tinged LED's. I think Doug Owen's phrase "yellow will penetrate, not 'flash back'" sums it up pretty well. I just want a scientific explanation of why this appears so. Maybe the presence of particulates and moisture tends to "scatter" light energy in the blue range of the spectrum? /ubbthreads/images/graemlins/icon3.gif

Re: Is white overrated?

CM, pretty much for the same reason the sky is blue.

Seriously!

The sky appears blue because of the refractions of light passing through it.

The opposite of blue (yellow) is refracted less and therefore appears to penetrate better and more sharply ... /ubbthreads/images/graemlins/smile.gif

Re: Is white overrated?

Tomas,

Well I guess that explains it all /ubbthreads/images/graemlins/smile.gif I do think I have a preference for lights with a *slight* yellow bias. There, I said it, now I'm a heretic /ubbthreads/images/graemlins/grin.gif

CM

Re: Is white overrated?

Let's deal with Red, Green and Blue. It's true that if you mix the colors, like in paint, you'll have black. From a physics perceptive, you've just subtracted colors, not added. If you mix Red, Green and Blue light (not paint), you have white. From a physics perceptive you've just added colors. This is what occurs in your color television, or your RGB monitors. It has no "white" light electron gun. It has only red, green and blue electron guns. All the colors you see are different mixtures of those colors, caused by the convergence of the three electron guns at the proper ratios in your RGB monitor.

When white light shines on an object, it absorbs all the colors of light except the color you see. In other words, an object that appears red, looks that way because it has absorbed all the blue and green light, and reflected only the red light. It's the same for blue objects. It absorbs the red and green light and reflects the blue. Now what happens with paint, like red, is your paint absorbs the green and blue light and reflects the red. As you add other colors to the paint you increase the number of colors it absorbs, and the light reflected approaches a darker or blacker color. When the paint finally absorbs all the colors it reflects none and is black. Just like darkness is black because of no light, an object is black because it reflects no frequency of light.

Perhaps this will help.
Color Addition
Color Subtraction

Edit: Hmmm.. I didn't see y'all posting all that while I was typing this up. Anyway, what Tomas said.

Re: Is white overrated?

OK, here is my explaination of why yeller is seen by human eyes better. The eye is composed of rods and cones. I think its the rods that see B & W, whilst it the cones that see color. But there are many more cones than rods, so anything that is rendered in a color will be seen sharper and better. This is why yeller glasses are so good for night driving. It is also well known that yellow-green is seen by the eye much better than other colors.

This gets me to wondering why we made red as STOP in traffic lights. Better to be a yellow green. But we cant change now.

Whilst I'm rambling on, did you know that bees see in Ultraviolet and some flowers shine brightly in UV light. So these flowers look like super bright LEDs to their furry eyes.
<font color="blue">--Ðøug</font> 2003.7.23.22.09.34 PT