# Where to buy XP-G Warm White R2 & Neutral White R3?



## okarina (Mar 24, 2010)

Hi! I wanna know where to buy XP-G Warm White R2 & Neutral White R3?


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## LEDninja (Mar 24, 2010)

:welcome:
Cree sells them in reels of 1000.
Do you want to buy reels of 1000 or just a few?
For a few try Cutter. (PM WeLight here or over at MP)

EDIT
There is a group buy over at CPFMP.
http://www.cpfmarketplace.com/mp/showthread.php?t=218933


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## okarina (Mar 24, 2010)

Thank You!

Cutter's got Warm White Q5. Maybe they don't have R2 bin, because it's new on the market.
I want warm white, because it emits more visible light. What do you think, the warm white R2 or the cool white R5 emit more visible light overall?


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## MichaelW (Mar 25, 2010)

What do you mean 'visible light'?
Maybe you mean 'useful light'? Once you move from cool-white to neutral-white you won't go back.
Cool-white: too much blue. Warm-white: too much red
Neutral-white: just right:thumbsup:


The outdoor-white seems like an interesting compromise between cool & neutral. Splits the performance difference: R5-cool, R3-neutral, R4-outdoor.
What I don't like is the reduced CRI. Why doesn't Cree show the SPD?


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## okarina (Mar 26, 2010)

MichaelW said:


> What do you mean 'visible light'?
> Maybe you mean 'useful light'? Once you move from cool-white to neutral-white you won't go back.
> Cool-white: too much blue. Warm-white: too much red
> Neutral-white: just right:thumbsup:
> ...



I mean that:







This is the Cree XP-G's Radiation diagram. You can see that the Warm White produces -i don't know- approximately 50% more light in the visible spectrum, than cool white and 30% more than neutral white.

So if I buy warm white R2 or Neutral R3, they will look brighter than a cool white R5, am I right?


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## spencer (Mar 26, 2010)

I don't think so because humans don't see all colours equally and the unit of the lumen is adjusted to account for that. I'm pretty sure that we percieve 1 lumen as the same brightness whether it is white, green, red, or blue.


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## Gryloc (Mar 26, 2010)

The flux binning determines how much light is produced. So, a R5 will definitely produce more light than a R2. The lumen curve is adjusted to the human eye sensitivity so a lumen of light is a lumen of light regardless of color or mix of colors. The overall brightness is already binned, so that is the perceivable brightness regardless of tint. Our eyes differ from person to person, so some tints or color temperatures will satisfy more than others. It comes down to preference of tint and the application of the light (white wall, indoors, outdoors, etc).

In concept, you are right about determining overall output (in lumens) by finding the area under the entire light frequency curve. However, those graphs are strictly used to show the proportions of colors perceived in each particular emitter color. The relative light output should be used to compare between the exact same color only. Therefore, for example, the graph was adjusted on the cool white so the blue spike peaks at 100%, while the second lump peak for the warm white was adjusted for 100%. I am assuming that if a Q5 bin of warm, neutral, and cool white was compared directly on the same graph, then that second lump (warmer colors) would be about the same for each color (deeper in the reds for the warmer tints), while the blue spike would appear to be very high for the cool white.

So, in the spirit of CPF, try both. Actually, try all three. Even though it is natural in the LED world now that cooler emitters are more efficient, and therefore, brighter, you may prefer the one tint over the other regardless to tint. All three tints are bright and useful, so do not worry about having a useless light afterward. 

Cheers,
Tony


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## okarina (Mar 27, 2010)

Gryloc said:


> The flux binning determines how much light is produced. So, a R5 will definitely produce more light than a R2. The lumen curve is adjusted to the human eye sensitivity so a lumen of light is a lumen of light regardless of color or mix of colors. The overall brightness is already binned, so that is the perceivable brightness regardless of tint. Our eyes differ from person to person, so some tints or color temperatures will satisfy more than others. It comes down to preference of tint and the application of the light (white wall, indoors, outdoors, etc).
> 
> In concept, you are right about determining overall output (in lumens) by finding the area under the entire light frequency curve. However, those graphs are strictly used to show the proportions of colors perceived in each particular emitter color. The relative light output should be used to compare between the exact same color only. Therefore, for example, the graph was adjusted on the cool white so the blue spike peaks at 100%, while the second lump peak for the warm white was adjusted for 100%. I am assuming that if a Q5 bin of warm, neutral, and cool white was compared directly on the same graph, then that second lump (warmer colors) would be about the same for each color (deeper in the reds for the warmer tints), while the blue spike would appear to be very high for the cool white.
> 
> ...



Thank you for the "fully" answer 

Now I'm more doubtful  but I would like to buy warm white. Finally maybe I will buy the one that sold on a 16-17mm star... It's hard to find. The nearest Star size I found is XP-G on a 14mm Star, but it's cool white 

I wanna put it in a Ultrafire C3 Steel flashlight and drive it directly with a Trustfire protected 14500.


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## riva (Mar 31, 2010)

I've been always questioning the necessity of the "normalization by maxium value" procedure, which may be cree's market strategy for selling more warm white leds.




Gryloc said:


> The flux binning determines how much light is produced. So, a R5 will definitely produce more light than a R2. The lumen curve is adjusted to the human eye sensitivity so a lumen of light is a lumen of light regardless of color or mix of colors. The overall brightness is already binned, so that is the perceivable brightness regardless of tint. Our eyes differ from person to person, so some tints or color temperatures will satisfy more than others. It comes down to preference of tint and the application of the light (white wall, indoors, outdoors, etc).
> 
> In concept, you are right about determining overall output (in lumens) by finding the area under the entire light frequency curve. However, those graphs are strictly used to show the proportions of colors perceived in each particular emitter color. The relative light output should be used to compare between the exact same color only. Therefore, for example, the graph was adjusted on the cool white so the blue spike peaks at 100%, while the second lump peak for the warm white was adjusted for 100%. I am assuming that if a Q5 bin of warm, neutral, and cool white was compared directly on the same graph, then that second lump (warmer colors) would be about the same for each color (deeper in the reds for the warmer tints), while the blue spike would appear to be very high for the cool white.
> 
> ...


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## ICUDoc (Mar 31, 2010)

Gryloc said:


> So, in the spirit of CPF, try both. Actually, try all three. Even though it is natural in the LED world now that cooler emitters are more efficient, and therefore, brighter, you may prefer the one tint over the other regardless to tint. All three tints are bright and useful, so do not worry about having a useless light afterward.
> Cheers,
> Tony



A good answer Tony- one of the weird things about LEDs is that althought the cooler tints are currently able to output more measured lumens for a given power input, the distribution of those lumens across the spectrum means that they may appear LESS bright if you shine them on a a scene with warmer colours in it! So a "brighter" torch on a white wall is LESS bright depending on use!!! This is where the incan boys enjoy the argument so much. My take on this is: use a light that works where you will be using it!


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## bee-man (Apr 2, 2010)

Cutter has an XPGWHT-01-5B1-R4-0-01 Neutral, but I would hate to spend 12 bucks shipping for only two emitters. Anyone in the US interested in a small group buy?


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## brted (Apr 2, 2010)

bee-man said:


> Cutter has an XPGWHT-01-5B1-R4-0-01 Neutral, but I would hate to spend 12 bucks shipping for only two emitters. Anyone in the US interested in a small group buy?


 
I wouldn't mind getting in on that for a couple of LED's. You might float the idea in the group buy section to gauge interest before taking firm orders. I know people love neutral white, so it seems like people could do a lot of upgrading. Seems crazy that Cree is in North Carolina and I'd have to go to Australia to get their LED's.


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## Inkidu (Apr 2, 2010)

Did anyone else notice that cutter has it as a neutral (L1)

and its bin # says (01) or outdoor white.

A guess its a typo I am still new to this so I could be wrong too.

I ordered 8 warm whites 3 days ago. Do they produce less light because

of the phosphors coating (thicker)??? Just curious. 

Thanks for any help.


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## herulach (Apr 2, 2010)

Inkidu said:


> Did anyone else notice that cutter has it as a neutral (L1)
> 
> and its bin # says (01) or outdoor white.
> 
> ...



The phosphor is less efficient at producing the red end of the spectrum than the blue, hence the lower output with the same die.

Outdoor white is somewhere between neutral and cool IIRC


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## Techjunkie (Apr 24, 2010)

DigiKey has them now, but they only have the bare emitters, without XP-G MCPCB stars.


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## zzonbi (Apr 25, 2010)

"Seems crazy that Cree is in North Carolina and I'd have to go to Australia to get their LED's."

Do you have a suspicion about that?

Regarding the actual spectrum, one can integrate the product of the eye sensitivity with each of the 3 curves and rescale according to bin.

I'd buy via Australia no problem if it wasn't for shipping. Anyone tried the star xpgs at kai? How are they?


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## Techjunkie (Apr 25, 2010)

zzonbi said:


> "Seems crazy that Cree is in North Carolina and I'd have to go to Australia to get their LED's."
> 
> Do you have a suspicion about that?
> 
> ...


 
I've tried a few of the 14mm from KD. The tint is good - cool, but not green or pink. 14mm is a pain in the butt to center if your torch calls for a 16mm star. A hair in each direction and focus is off. They finally got some 16mm stars in so I've ordered those and some 5000K neutral white XPG from digi-key. I'm gonna roll my own.


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## txg (Apr 25, 2010)

how do you know there is a warm white r2 bin? the actual datasheet only lists q5 as the highest bin. edit: sorry, my fault. it seems like they actually exist if you're looking in the binning and labeling pdf, but they are only available in 3500k, which is perhaps a bit too cold if mixed with normal halogen room lighting.


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## RusDyr (Apr 27, 2010)

bee-man said:


> Cutter has an XPGWHT-01-5B1-R4-0-01 Neutral, but I would hate to spend 12 bucks shipping for only two emitters. Anyone in the US interested in a small group buy?


There is free shipping at cutter if your order is more than 100$. 
I've just ordered 20 XP-G R4 at 20mm star to Russia, with price break and CPFDISCOUNT coupon it costs about *5,5$* per LED. Isn't it nice, ah?


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## blasterman (Apr 27, 2010)

> Seems crazy that Cree is in North Carolina and I'd have to go to Australia to get their LED's.


 
The answer to this is likely because they aren't made in the U.S. However, this is the case with most LEDs, and the bigger question is why other brands like Bridelux have a substantial N American supply chain while Cree doesn't.


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## RusDyr (Apr 28, 2010)

Make a flashmob by asking Cree WTF.  Might be this will help.

BTW, are there Luminus available?


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## txg (May 6, 2010)

did anyone receive a warmwhite xp-g and has some opinions on it yet? 

my warm white q5s arrived today, and i'm testing them at the moment, four of them in series on a cpu cooler, driven by a constant current source up to 1.6 Amps. to be honest, i'm actually not as pleased as expected. brightness ist definitely good, but i wouldn't recommend to use these leds as a room light (which was my plan). in my opinion, even a cheap (1,33€) standard 11w ccfl looks better, because the xp-g is missing the reds, everything looks greenish, this is absolutely not acceptable for my living room. 

i hoped for a better color, because cree states a cri of 80, which is the same as with cheap ccfls. color temp (stated is 3000k) seems to be nice, not as warm as ccfls but not too cold, in my opinion this is rather 3500k to 4000k. 

now i'm glad that i decided to only buy four of them, but i have no idea what to do with them now.


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## syc (May 7, 2010)

What happens if you drive them at a lower current, like 700ma? Does the color become less greenish? I was planning on a small GB, and wanted to use a few for home lighting - but I may have a domestic revolt if I start putting up greenish lighting.

Steve



txg said:


> my warm white q5s arrived today, and i'm testing them at the moment, four of them in series on a cpu cooler, driven by a constant current source up to 1.6 Amps. to be honest, i'm actually not as pleased as expected. brightness ist definitely good, but i wouldn't recommend to use these leds as a room light (which was my plan). in my opinion, even a cheap (1,33€) standard 11w ccfl looks better, because the xp-g is missing the reds, everything looks greenish, this is absolutely not acceptable for my living room.
> 
> i hoped for a better color, because cree states a cri of 80, which is the same as with cheap ccfls. color temp (stated is 3000k) seems to be nice, not as warm as ccfls but not too cold, in my opinion this is rather 3500k to 4000k.
> 
> now i'm glad that i decided to only buy four of them, but i have no idea what to do with them now.


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## uk_caver (May 7, 2010)

txg said:


> did anyone receive a warmwhite xp-g and has some opinions on it yet?
> 
> my warm white q5s arrived today, and i'm testing them at the moment...


What colour bin were the q5s?


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## txg (May 7, 2010)

the greenish color stays there with lower drive currents, but i believe that it is a tad less annoying.

the bin of these xp-g is 7D.


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## uk_caver (May 7, 2010)

I got a couple of those to play with, but I haven't got round to sticking them in anything yet.


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