colors of white

[docb]

I see reference to cool and neutral and such, but where can we see examples or descriptions of what these different whites actually look like?

 

[znomit]

I see reference to cool and neutral and such, but where can we see examples or descriptions of what these different whites actually look like?

Not too far away
http://www.candlepowerforums.com/vb/showthread.php?t=156772

 

[docb]

I see the charts, but am looking more for a general desription of what those colors name mean.

Some are more blueish? or more like fluorescent lights? More yellow like regular bulbs?

 

[carrot]

Cool -> blue
Warm -> red
"Neutral" -> golden yellow

There's no nice terms associated with greenish or purplish tints, although there are at least a good bit of us who prefer a greenish-yellowish tint over most other tins. Seems, however, that more people do not. I suspect that those who use their lights outdoors substantially like the greenish tint, and those who use their lights indoors substantially like the bluish tint.

 

[docb]

thanks very much!

not sure what tint I'll like yet

 

[yellow]

full "neutral White" then

 

[HarryN]

If you own a fluorescent bulb fixture in your house, then the test is easy. Just go to a good hardware store, and they will have the standard 4 ft bulbs in the different white "colors" and in some cases, standard and high CRI type.

Some other approximate references points:

- Standard incan bulbs - about 2900K (considered "warm")
- Noon day sun light - about 6500K (considered "cool")
- Conventional camera flash - around 5700K (considered "cool to neutral")

The white color you like is at least partically dependent on your age, genetics, and what you wife likes.

It is easy to mistake the CCT color temperature you think you like, with the amount of spectral content in a light, which actually most people like. For instance, I strongly prefer cool white colors of white, but I like a lot of spectral quality (not missing areas in the spectrum)

For this reason, HID is just a winner, even though it has almost too much blue for my taste.

I frankly can't stand warm color LEDs or incans that aren't over driven (raises the CCT)

The balance I end up at is about 4000K and a full spectrum content LED, but everyone is different.

 

[PolarBearX]

i have a number of kelvin charts on my pc that I reference..most are for photography and auto lights :thumbsup: ..this one is good for flashlights if it helps

PBX

 

[docb]

Maybe I prefer incandescent indoors, and love sunlight the best, but the very cheap florescent tubes I have in my garage have a weird glow I kind of like too.

 

[blasterman]

Perceptually most people prefer a warmer color indoors during the evening, and a more active color for working, or at the office. This is why a lot of corporations are moving towards 'daylight' balanced fluorescent tubes around 5000k because the perception of being outside undoor noon day sun tends to increase activity. Warmer however light tends to wind people down.

Around 4100k is considered 'neutral' as a general industry standard, and this is the dominant color in clinical hospitals, Q/C labs, data centers, blah, blah, blah.

There is a big technical difference between warm-white / neutral-white vs cool white emitters. Cool-white LEDs have a limited spectral response which tends to give them either a green or blue/purple tint, but this also gives them greater efficiency because blue and green are more efficient colors for LEDs to generate.

Neutral-White and warm-white emitters have additional amber and red which gives them better color, but amber and red are less efficient colors for LEDs to produce. So, cool-white LEDs will always have the brightness edge over neutral-white and warm-white. However, given the increasing push for interiour lighting considerations we're seeing more improvements in the neutral-white range around 4100-4500k.

 

[jeffosborne]

Here's another way to look at the color temperatures, on a Planck chart. The line is the 'black locus', which represents the color that a black body emitter will generate at various temperatures. Specifically, this is what a tungsten wire in a vacuum will produce at those temps.

Note that the line travels from red to blue, but does not venture into the green above, or magenta below. Manufacturers like Phillips use this when the define various 'bins' for cool, neutral, and warm whites. Here's a chart for a neutral white Rebel LED:

And here's a look at two of those bins: The warmer LED in the center is a RM bin, the warmest neutral white offered. It also is a tad on the green side. The two outer LEDs are the SN bin, closer the the black body locus, and not as warm as the center emitter.

The area around this light looks very warm because it is light from an incandescent bulb.
How's that for a look!
Cheers,
Jeff