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Thread: Cree XR-E at 240 lumens?

  1. #1

    Default Cree XR-E at 240 lumens?

    http://cgi.ebay.co.uk/ws/eBayISAPI.d...MEWA:IT&ih=009

    Anyone know if that's real? I checked with Cree's website, and they don't seem to claim anything beyond 176 lumens.

  2. #2

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    Definitely not a real figure. This guy's extrapolating numbers that won't work in reality. P4's do approx. 180 lumens @ 1A, but the curve starts to get pretty flat beyond that. Even a Q5 won't hit 240 as far as I know.

    R bin's could be a different story though, when they come out. IIRC, R's will of course have higher luminous flux, but will also represent a large leap in efficiency, producing less heat, therefore allowing higher levels of overdrive. But I digress...

    Getting back to the point... this auction sucks. He's asking a bit much for the LED (almost $12 US... a Q2 is going for $14), doesn't specify the tint (anyone can say "white"... is it WC, WD, WG, etc.?), a P4 is NOT "neu" as he claims (Q's are easily attainable now), his lumens figure is way off, and the final kicker... he has 100% positive feedback. That always rings of "cheese" to me.

    Doctor - are you looking for Cree's? Much better deals at CPF's Group Buy section, and/or through the individuals and dealers that frequent the place. I'll be back with a link in two shakes of a lamb's tail.

    Edit: Heh... what's better than one link? Two links!

    Group Buy** Q2 Cree XR-E emitters. Available now!

    Group Buy for Q5 Cree (107 Lumens Min - 113 Lumens Max) at 350mA, LED Available NOW!

    2nd Edit: I'm almost wrong about the Q5's. Seems they can get up to about 220 Lm @ 1A.
    Last edited by PNjunction; 07-03-2007 at 13:36.
    Alas, poor diode. I fried him well.

  3. #3
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    Talking

    Let's just say expect 1200+ from a single Lumileds unit about by Christmas next year. I have 2 on my desk now.
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  4. #4

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    A post like that with no detail? You sir, are a menace to society!

    Alas, poor diode. I fried him well.

  5. #5
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    If I could tell you more I would! I can tell you it's about 15x15mm.
    CLICKY!!!

    Admin: In the immortal words of Captain Planet: YOU HAVE THE POWER
    Admin: (To quit being a bitch)

  6. #6

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    Quote Originally Posted by PNjunction View Post
    Definitely not a real figure. This guy's extrapolating numbers that won't work in reality. P4's do approx. 180 lumens @ 1A, but the curve starts to get pretty flat beyond that. Even a Q5 won't hit 240 as far as I know.

    R bin's could be a different story though, when they come out. IIRC, R's will of course have higher luminous flux, but will also represent a large leap in efficiency, producing less heat, therefore allowing higher levels of overdrive. But I digress...

    Getting back to the point... this auction sucks. He's asking a bit much for the LED (almost $12 US... a Q2 is going for $14), doesn't specify the tint (anyone can say "white"... is it WC, WD, WG, etc.?), a P4 is NOT "neu" as he claims (Q's are easily attainable now), his lumens figure is way off, and the final kicker... he has 100% positive feedback. That always rings of "cheese" to me.

    Doctor - are you looking for Cree's? Much better deals at CPF's Group Buy section, and/or through the individuals and dealers that frequent the place. I'll be back with a link in two shakes of a lamb's tail.

    Edit: Heh... what's better than one link? Two links!

    Group Buy** Q2 Cree XR-E emitters. Available now!

    Group Buy for Q5 Cree (107 Lumens Min - 113 Lumens Max) at 350mA, LED Available NOW!

    2nd Edit: I'm almost wrong about the Q5's. Seems they can get up to about 220 Lm @ 1A.


    Thankyou, great info. I'm ok with the P4 though, there's not a lot of difference between 176 and 220 lumens, certainly less than the difference in cost, even if the LED in that listing is expensive. It's not that bad actually, unless you have to buy loads, you'd want a discount then.

    I'd buy a couple of XR-E Q5's though, if anyone can sell me them without difficulty, and if they have a colour that isn't too strong in the blue end, I want some good rendering of red objects from its light... I'm in the UK, but they're very small, letter post in a padded envelope should be fine. I'd be paying by Paypal if I bought some, most likely.

    Ben, is that Lumiled a small emitter? Or is that area you described the whole active area? Whatever it is, I want to know if Cree might also be about to release one within months. That power is a match for a 240V 100W incandescent, and if the colour is nice I'll be wanting several eventually, screw CFL,s, overhyped potentially incendiary garbage...

  7. #7
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    Default

    In my opinion, Cree products are crap. The 2 engineers who designed the package left Lumileds for Cree when the lighting devision was just getting started. Their product has major flaws and is not a good clean 'white'. The glass lens is stuck on with a small dab of glue at either end and can be knocked out of place very easily. The Luxeon product on the other hand is a much warmer color temperature, has a better package design with better lens, and are brighter. Very soon there will be K2 product out there that actually are rated for 240 lumens.
    Unfortunately I cannot tell you much more about the high power luxeons. I can tell you the emitter will be 4 times as efficient as anything before.
    CLICKY!!!

    Admin: In the immortal words of Captain Planet: YOU HAVE THE POWER
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  8. #8

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    Doctor - Correct... you won't see much difference between 176 and 220. More important to get a hold of a preferred tint. The P4 used in my Excrelamp is a WC, and although it's not bad at all, it is ever so slightly on the blue side. Keeping an eye out for a WD to replace it (no luck yet)...comparable to a Lux W0, which is my favorite tint.

    For your purposes, you might do well with the Q2 buy linked above. They're WG, available right now, and the price has dropped to $12 US as of today. Global priority shipping is $11, but that's only roughly $4 more than Mr. 240 Lumens.

    BTW, just realized the price of those Q5's... $22 per emitter!

    One more thing... what kind of host are you thinking of using? Much of the Cree's output is within a 75 degree angle, so it may not perform as well with many smaller, and/or shallower reflectors that aren't designed for the XR-E.

    Ben - Yes, the domes can, and do get knocked off pretty easily. At least they're using better phosphor than SSC... yuck (where's the barfing smiley?). Better meaning less sensitive to tint shift toward blue over time, especially under high current. All kinds of nastiness seems to be happening with the SSC gel domes as well... yellowing, browning, clouding, etc. Overall, I also much prefer Lumileds' quality.

    As for the K2, do you mean this is a newer and better one that will live up to the hype that the first one failed to? That sounds like a jab, but it's not. Just that a lot of people were disappointed with the K2's performance. IIRC, it couldn't take anywhere near the heat it was supposed to. If it's a good piece though, it could make an excellent P4 replacement in my above mentioned lamp. I'd really like much wider dispersion.

    Now, about this other new Lux. Have you been sworn to secrecy? We may need to resort to some good old fashioned torture here... hehe.
    Alas, poor diode. I fried him well.

  9. #9
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    Quote Originally Posted by PNjunction View Post
    Ben - Yes, the domes can, and do get knocked off pretty easily. At least they're using better phosphor than SSC... yuck (where's the barfing smiley?). Better meaning less sensitive to tint shift toward blue over time, especially under high current. All kinds of nastiness seems to be happening with the SSC gel domes as well... yellowing, browning, clouding, etc. Overall, I also much prefer Lumileds' quality.

    As for the K2, do you mean this is a newer and better one that will live up to the hype that the first one failed to? That sounds like a jab, but it's not. Just that a lot of people were disappointed with the K2's performance. IIRC, it couldn't take anywhere near the heat it was supposed to. If it's a good piece though, it could make an excellent P4 replacement in my above mentioned lamp. I'd really like much wider dispersion.

    Now, about this other new Lux. Have you been sworn to secrecy? We may need to resort to some good old fashioned torture here... hehe.
    To answer the first question, Cree is using phosphor plates and released lower quality unity with high brightness sooner. Lumileds may be a little slow to release products but the end product is much higher quality because it has been tested better and to higher standards. Cree tests about 1 in a 1000 units for functionallity. Lumileds on the other hand tests EVERY die before the wafer is cut. The die are tested individually at 350, 500, 750, 1000, 1250, 1500, and 1750mA. They are pulsed very fast, a spectrometer takes a spectra measurement and brightness measurement for every die at every power level. This allows the LEDs to be sorted into bins based on color temperature and light output. After they are packaged, 1 in 100 is tested using the same method.

    As for the browning of the lenses, That should never happen unless the LED is run at >300 degrees for extended periods of time. The gel lenses go through a reflow oven to solder the LED to the star.

    I am essentially sworn to secrecy because if I tell you any more, something bad could happen!
    CLICKY!!!

    Admin: In the immortal words of Captain Planet: YOU HAVE THE POWER
    Admin: (To quit being a bitch)

  10. #10

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    Quote Originally Posted by Laser Ben View Post
    I am essentially sworn to secrecy because if I tell you any more, something bad could happen!

    Well, we wouldn't want that! So for now, I'll have to be content with guessing, and waiting for the eventual announcement. Speaking of guessing... on a hunch, I divided 1200 by 80. Obviously, the answer is 15. The Rebel die is 1mm square, isn't it? 80 Lm @ 350mA. See where I'm going with this?

    So, what's all this about a new K2? Hmmm?

    BTW... LOL @ > 300 degrees. Knowing the assortment of nut jobs at CPF, no wonder their Seoul domes are turning various colors.
    Alas, poor diode. I fried him well.

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