Afrosheen

Because the further down the spectrum you go towards blue/purple, the longer the wavelength. Your eyes prefer shorter wavelengths at night (red/yellow) which focus in front of the retina, rather than behind it like blue does. The light output as color skews towards blue has to go up logarithmically to compensate.

jarabanos

peteharvey

Are you sure about blue having longer wavelengths, while red/yellows have shorter wavelengths?

I have a science background, and red, infrared, microwaves, and radio waves have the lowest frequencies, with the longest wavelengths.
Meanwhile blue, ultraviolet, x-rays, and gamma rays have the highest frequencies, with the shortest wavelengths.

Otherwise, I do understand your idea about eyes having a preference for red over blue.

Bigjon3475

iTrader: (2)

Direct sunlight is about 5500 - 5750 kelvin. Six thousand kelvin is about as close as you can get. Obviously direct sunlight would be what your eyes evolved best to see.

xRYD3Rx

I currently have philips ultinon 6000k on my car light output in the best can't compare it with any other bulb.

patbateman

Eh I think you have that reversed. Blue light wavelength is ~450nm, red is ~650nm. And the shorter the wavelength the higher the frequency.

SW17LS

This is not a question guys...this is science.

6000K HIDs put out less lumens (usable light) than 4100-4300k OEM HIDs. Thats a fact, its not up for debate. Look at Philips descriptions themselves, they publish the lumen figures for their bulbs. I think their OEM 4100k bulb is something like 3300 lumens while their 6000k bulb is 2700 lumens. Less lumens = less usable light.

Whether that bothers you or not is up to you, but they do produce less light.

At some point I am planning on trying the Osram CBI bulbs which just recently have come out in Lexus' D4S size. 5k color temperature with 3300 lumens.

Bigjon3475

iTrader: (2)

I don't think anyone said a lower lumen rating is brighter or equivalent. In almost every instance bulbs that have higher kelvin ratings have higher lumen ratings. If Phillips makes their higher kelvin bulbs have a lower lumen rating then there's a reason for that. Mainly that they know the human eye evolved with direct sunlight so the human eye is more sensitive to that particular color, 5750K or so...

Anyways, best of luck finding bulbs you like. I miss the really blue bulbs they used to sell..

bclexus

Kelvin color temperature (e.g. 4100K, 6000K, etc.) is the COLOR of the light produced, and really has nothing to do with the amount of visible brightness of the light (lumens) produced...except that the human eye visually sees certain colors easier than others.

Kelvin temperature is the color - e.g. looking at an incandescent lamp (warm spectrum) versus looking at blue sky, away from the direct sun (blue spectrum).

Lumens is the brightness from the light source - e.g. a match flame versus metal-halide street light.

xRYD3Rx

You don't unscrew that bolt as soon as you remove that square ballast off the bulb you will see the metal clips you push and move it left or right depends which side you want to take out first and they come out of place. Changing bulb takes 5-10 minutes for a body shop or dealer charging $60-100 that's ridiculous lol. But I will agree with you driver side was a pain I also changed my driver side blinker was horrible got bloody fingers at the end lol.

SW17LS

This statement is not at all accurate. The higher the color temperature the lower the output, lower the lumens.

Otherwise, why would Osram specifically have developed a bulb with higher color temps that specifically maintains the lumens of output of the OEM Bulbs?

Some sources:

http://www.theretrofitsource.com/com...l#.VbFvVXjDlpE

This is a great chart. Look at the color temps, the higher the color temps, the lower the lumens:

http://www.everythingcobalt.com/hid-color-chart/

http://headlightretrofits.com/bulbs-...-kelvin-color/

[quote]HID Kelvin Color
We often get the question: “Doesn’t a higher number mean it’s brighter or better ?”. The short answer – NO. When talking about an HID bulb Kelvin Color temperature, a 4100-4300K HID bulb is the brightest Kelvin Temperature you can get. This is the OEM coloring specification on most vehicles with factory HID headlights for a reason.
Let’s explain…
Light output is measured in luminosity or lumens. A 4300k HID bulb at 35 watts generally produces 3200-3400 lumens of light. As Kelvin Color Temperature starts to go up (5000k, 6000k and above) luminosity decreases.
A 5000k HID bulb at 35 watts generally produces 3000 lumens and a 6000k HID bulb at 35 watts generally produces in the 2800 lumen range. The lumen output above 6000k starts to dramatically decrease, which is why we never recommend anything above 6000k for an HID bulb. Anything above 6000k should be regarded as cosmetic or show only.
“Why do my friend’s headlights look brighter than mine and he has xxxx-K temperature bulbs???”- The reason higher Kelvin bulbs may appear brighter is that they are actually glaring more off of the road surface. Glare is NOT how light output is measured. It’s annoying, obnoxious and dangerous. Anything above a 6000K color rating is extremely ineffective & can be deemed practically useless. 6000K is generally the highest Kelvin rating you can go without creating too much glare. The higher the Kelvin rating, the lower the lumen output is. (We can’t stress this fact enough…so we noted it twice)
When the Kelvin rating is above 6000K, generally the lumen rating is around 2000 or below. This actually puts the HID output level back in the category of Halogen Output.[/b]

OEM HIDs are 4100-4300k for a reason, because these temps give off the most usable light output. I agree 5000-6000 depending on the application looks better, but generally with less usable light output as a tradeoff.

peteharvey

Actually, when the color temperature falls too low, that is, too much towards the red range, then the lumen output falls too.

Lumen output is at its best in the neutral range.

SW17LS

Correct...and that neutral range for HIDs is in the 3500-4500k range.

Bigjon3475

iTrader: (2)

Not to be an azz but did manufacturers start making light bulbs for another life form other than humans?

If the answer is no then there's a very specific light temperature that is particularly useful to human beings. Think millions and millions of years staring at things lit by, and given life by, our sun.

Think about that for a bit before you go off on anymore tangents. Thanks.

SW17LS

Can you provide any sources or documentation that refutes any of the sources and documentation I provided above? I'm not just making this stuff up.

You said that lumens increase as color temperature increases. That is false and I provided the sources to back that up.