No More B5 S4

4,300K

chuangs4

they were exactly 8000k....

MelloYelloS4:Indkted

Thanks. What is optimal color temp for most usable light?

No More B5 S4

...but in general, through evolution, we see best in day light: ~4,600K to ~5,200K.

You get the most lumens output from 4,300K bulbs. Here's an approximation:

4,300K: 3,000 to 3,200 lumens
5,400K: 2,600 to 2,800 lumens
6,000K: 2,200 to 2,300 lumens

So in terms of all total light output (lumens), 4,300K will yields the most light. With the 5,400K you lose just over 10% of the lumens output but what you lose in lumens you *may* gain in contrast. The light is whiter since you appear to see more, better contrast.

There are some that swear they see more with 6,000K even though there's a 30% or more loss of lumens. Here are some answers:

On white pavement or lighter surfaces, blue and blue-purple hue (5,400K to 6,000K) reflects better than white/white yellow (4,300K). So the light appears enhanced. However, on black pavement, blue and especially purple gets absorbed and is not effective whereas yellow is much more effective at not getting absorbed.

There's a lot of other "speculation" when discussing automotive lighting such as Color Rendering Index (CRI) and the Department of Transportation (DOT) argues with light experts about this and that for many years (with respect to HID).

The bottom line is, it goes back to the original saying, everyone sees differently. Each person's eyes react differently to colors, hues, tones, glare and contrast. So why is 4,300K chosen as the color for OEM HIDs? It's the best all-around color, in general.

So to answer your question, what is the optimal color temperature depends on you and your optical acuity, the color of the pavement you are driving on and a few other things.

But, in general, I would say the optimal color termperature is: 4,300K to 5,200K. My eyes prefer the whiter, bluer color so I would go with the Osram Xenarc 5,400K bulbs (which is actually 5,300K-don't ask why they call it 5,400K).

Hope this helps. :-)

S4 TTime

agree with you that 4300-5200k lumens is the optimal range for lighting.

No More B5 S4

...it actually adds yellow to the color spectrum. If you are OK with the color, then no problem but if you want whiter light, you would have to upgrade to 5,400K or higher color temperature bulbs.

For instance, 5,400K at 50 watt = ~4,100K

I'm using 8,000K bulbs at 50 watt.

S4 TTime

Thanks for the info. It makes sense now that I think about it.