How do Rebel and Seoul LEDs compare with Cree?

[gunfighter]

Do the Rebel and Seoul LEDs have bin numbers just like the Cree nomenclature or are they all the same?

I can only find information on Cree binning and labeling;

http://www.cree.com/products/pdf/XLamp7090XR-E_B&L.pdf

 

[gunfighter]

UPDATE:

I did end up finding binning and labeling for the Seoul LED

http://http://www.essc.co.kr/_HOMEPAGE/home_kor/product/spec/P4_BL.pdf

 

[yellow]

If You do succeed in finding a Rebel datasheet, mentionning output a a certain power, max power allowed (and output there) and some things to heat,
please post it here, too

cuz I happen to read all these posts from the Luxeon-guys, that the rebel is better than Cree but never run into something "printed"

 

[ingokl]

http://www.lumileds.com/pdfs/DS56.pdf

 

[Bogus1]

For easy comparison between LEDs DFiorentino posted these graphs and charts.

 

[Ron Schroeder]

Best Rebel about 100 Lm at 350ma and about 135 Lm/Watt at 20ma.

Best Cree 107 to 114 Lm at 350ma. But I think the Revels have a slightly lower Vf than the Cree so the Rebel would be a bit better Lm/Watt.

Best Seoul bin (U) is 91 to 118.5 LM at 1 Watt. ma. not specified.

 

[jeffosborne]

Hey, one other important spec regarding Cree/Seoul/Rebel, is that the Luxeon Rebel has the best white tint, and the smoothest dispersion pattern. This is important to me in using my lights for photography.
Here's a light that I clip to my belt (main unit on right) and the slave unit (on left) that I hold in my left hand. The slave, with optics, ARE Cree LED's, the main unit uses Luxeon K-2. Batteries in the main unit are 3 18650's:

 

[jrv]

Best Rebel ... about 135 Lm/Watt at 20ma.

From memory that's about 20% of thermodynamic ideal. Amazing.

 

[regulator]

One thing to note is that there are a lot of criteria/parameters to look at in LED's.

One LED may offer the highest output but may not be the most efficient.

Another LED may be the most efficient at a higher output may may not be the brightest.

Another LED may be the most effiecient at lower outputs but cannot offer highest output.

Tradeoffs is the name of the game and unfortunately Marketing can sway people into thinking one product is better than another by only looking at one criteria.

 

[FlashCrazy]

Another thing to note is the Rebel bin that is 100 lumens @ 350 mA is only for the "cool" tint. Neutral white tint drops to 80 lumens, and if you want a warm tint, it's only 60 lumems @ 350 mA.

 

[Luminescent]

Another thing to note is the Rebel bin that is 100 lumens @ 350 mA is only for the "cool" tint. Neutral white tint drops to 80 lumens, and if you want a warm tint, it's only 60 lumems @ 350 mA.

All the major vendors tend toward the cool side for their highest output bins, but for what it's worth, the Rebels I have seen so far were on a par with, or just slightly warmer than even my best CREE lights.

All vendors are somewhat variable on color, so It's a little premature to generalize this, but in the past, even the cool-white luxeons were typically a little warmer than CREE's and SSC's (though not as efficient). Now the Rebels have closed the gap on Lumens/Watt, and also seem to have held onto their slight edge in color rendering. I hope Lumiled doesn't let the color consistency of the Rebels suffer as they ramp up production, because I think this is one of their competitive advantages. Time will tell.

 

[FlashCrazy]

...for what it's worth, the Rebels I have seen so far were on a par with, or just slightly warmer than even my best CREE lights.

All vendors are somewhat variable on color, so It's a little premature to generalize this, but in the past, even the cool-white luxeons were typically a little warmer than CREE's and SSC's...

I just compared the color bin charts of the Rebel, Seoul, and Cree LEDs. You're right, the Rebels are binned more towards the warm side. I think that's great, as I prefer warmer tints...it's nice to see that the Rebel 100 "cool" bin is actually quite warm. Thanks for the heads up.

 

[Gaffle]

I hope Lumiled doesn't let the color consistency of the Rebels suffer as they ramp up production, because I think this is one of their competitive advantages. Time will tell.

I do not own a Rebel yet, but all of the posts/pictures that I have seen went toward the warm spectrum. Hallelujah. I am being optimistic, but it feels like the Rebel will have the advantage for a little bit here. I would rather have a warmer Rebel than the top-of-the-line brighter Cree (with a tint that is on the cool side).

I just wish there was a Rebel that would replace the current Luxeon stars.

 

[lexina]

I just wish there was a Rebel that would replace the current Luxeon stars.

It's only a 080 but at least it comes in a star!

http://www.dealextreme.com/details.dx/sku.8405

 

[yellow]

I would rather have a warmer Rebel than the top-of-the-line brighter Cree (with a tint that is on the cool side).
I just wish there was a Rebel that would replace the current Luxeon stars.

but by now there was never a coice of the bin with the rebels,
the Crees were sold by their bins (at least the ones I got from group buys here), so the rebels can still be lemons.

I absolutely agree on the package, as long as they are only like now, I'm going to use up my remaining Cree and Seoul

 

[Luminescent]

It's only a 080 but at least it comes in a star!

I think Gaffle was talking about a 'standard' Luxeon 20 mm star which is optically compatible with the older Luxeon.

The DX version is a small star, so it won't "drop-in" on most standard 20mm mounts, and even if it did there would be the same kind of focus issues you run into on CREE stars in Luxeon lights, because the emitter optical axis is lower compared to the older Luxeon.

I ran into this myself when I got some blank 20mm stars from led-tech.de in Germany, and mounted some Rebel-100's on them. I found that to get them to focus properly in older Luxeon lights is a PITA, because unlike the older Luxeons, the Rebel is not setting on top of a round pellet that lifts it up inside the reflector. You have to shim the star up just slighly to put the emitter optical axis at the same height as the old luxeon's optical axis, and in some cases this means that a small amount needs to be trimmed off the back of the lights reflector to give clearance. It does work well once you get it in the correct position optically because the rebels 'lambertian' pattern matches the older luxeons reasonably well (unlike the CREE which is a bit narrower).

Lumiled could easily eliminate ALL these headaches by simply making the Rebel die also available on a Luxeon pellet style base. Then they would be perfect 'drop-ins' for existing Luxeon light designs (except 2 to 4 times the output).

 

[Gaffle]

I think Gaffle was talking about a 'standard' Luxeon 20 mm star which is optically compatible with the older Luxeon.

Correct. Example, swap out the Luxeon star inside the ProPoly and replace with a compatible Rebel star.

Aren't the Rebel emitters much smaller then the Luxeon/Seoul emitters?

 

[lexina]

I think Gaffle was talking about a 'standard' Luxeon 20 mm star which is optically compatible with the older Luxeon.

The DX version is a small star, so it won't "drop-in" on most standard 20mm mounts, and even if it did there would be the same kind of focus issues you run into on CREE stars in Luxeon lights, because the emitter optical axis is lower compared to the older Luxeon.

I ran into this myself when I got some blank 20mm stars from led-tech.de in Germany, and mounted some Rebel-100's on them. I found that to get them to focus properly in older Luxeon lights is a PITA, because unlike the older Luxeons, the Rebel is not setting on top of a round pellet that lifts it up inside the reflector. You have to shim the star up just slighly to put the emitter optical axis at the same height as the old luxeon's optical axis, and in some cases this means that a small amount needs to be trimmed off the back of the lights reflector to give clearance. It does work well once you get it in the correct position optically because the rebels 'lambertian' pattern matches the older luxeons reasonably well (unlike the CREE which is a bit narrower).

Lumiled could easily eliminate ALL these headaches by simply making the Rebel die also available on a Luxeon pellet style base. Then they would be perfect 'drop-ins' for existing Luxeon light designs (except 2 to 4 times the output).

That's very true. Part of the problem is also that we are trying to use the old luxeon reflectors for the newer leds (Seouls, Crees and Rebels) and often, this doesn't work without some tweaking. I suspect the led manufacturers will carry on trying to make the best product they can and expect flashlight manufacturers to design around their leds. Kind of the same anguish I get whenever Intel/AMD change their pin-connections for their CPUs every few generations!

 

[Luminescent]

That's very true. Part of the problem is also that we are trying to use the old luxeon reflectors for the newer leds (Seouls, Crees and Rebels) and often, this doesn't work without some tweaking. I suspect the led manufacturers will carry on trying to make the best product they can and expect flashlight manufacturers to design around their leds. Kind of the same anguish I get whenever Intel/AMD change their pin-connections for their CPUs every few generations!

With it's 'lambertian' flux pattern, the Rebel is a pretty good match for the older Luxeon reflectors optically if you can get the Rebel mounted so it's optical axis is in the right position. In this regard the Rebel is less of a hassle than the CREE, which has a narrower pattern such that a lot of the light will miss some higher F-Ratio Reflectors that would work fine for the Luxeon or Rebel.

I have found some standard 20mm star boards that are set up for the Rebel, which will at least keep them properly centered, which solves the problem on two of the three 3D axises.

The remaining axis, which is still a problem, is HEIGHT. The older Luxeon devices had the emitter chip on top of a little pellet, where the Rebel emitter chip is on a tiny low profile surface mount pad.

If Lumiled won't mount the Rebel in a Luxeon star style package, some aftermarket company could easily mount the existing Rebel on a 20mm star board with a bump in the center high enough to create a nice raised mounting pad to lift the Rebel up just enough so it's emitter chip will be at the same height as the emitter chip on the older Luxeon III. With this type star mount the alignment would be correct on all three axises and you could just drop this star into any light that was working properly with the older luxeon star.


So it is possible, but I haven't yet seen such a height adjusted star.