How can a 5w luxeon be rated at 120 lumens?

[socalrunner]

I have totally bought into all the new Cree XR-E Technology and have been using a L1D for a bike helmet light.. This is a supplement to my handlebar light. Works great for looking through corners and the strobe mode gets every drivers attention. Prior to this I almost bought a Dinotte headlight which uses a 5W luxeon and they rate it at 120 lumens.

http://www.dinottelighting.com/DiNotte_Lighting_Ultra_5.htm

How much are they overstating there lumens? I mean some of the best surefire 5w flashlights only go to 100 lumens.. I tell my friend to just go with one of the smaller Fenix lights, they use 1-aa battery and get the same burn rate as the dinotte which uses 4-aa batteries..

All I keep getting back is well 120 lumens is brighter than 90 lumens. Help my friend see the light because he needs some convincing..

 

[270winchester]

not much, if they are talking about bulb lumen without reflector and heat loss. I have a X-bin LED in an L4 that pumps out 190+ lumens before reflector loss. THe average V bin makes between 110 and 140 so there are a lot of room for overly-optimistic specs,

the W bin is between 140 and 190, X bin 190-240. The X bin still represents a good efficiency(the pinnacle of the last generation of Luxeons)

 

[Kiessling]

This is a difficult topic.
Most manufacturers overstate their lumen and runtime ratings, which makes comparisons problematic.

With a good bin LuxV you can very well get 120lm out of the front of a light at the recommended drive current. If Dinotte is driving their LuxV at about 700mA and use good bins then their 120lm rating could be accurate.

Surefire typically underrates the average light as they state a minimum luminous flux you'll get out of the business end. And some LuxV lights of them are rated at 100lm which is about the same as the Dinotte.

Now ... fenix ... they do present flux ratings of the bare LED in a theoretical envirnonment, meaning untested in real product. At least it seems this way. Typically a Fenix light is quite iverrated in luminous flux. But comparisons between the models seem to be realistic.

A LED with the EZ1000 chip (Cree XR-E or Seoul P4) will not be brighter than a LuxV. It will be more efficient.

bernie

 

[cratz2]

Yeah, a hard-driven Lux V (W bin or esp an X bin) can be very, very bright. Just most manufacturers don't drive them to spec because of heat issues. They develop a lot more heat than Crees and SSCs do.

Also, Lux V lights tend to have wider hotspots than Lux IIIs/Crees/SSCs. That's neither good nor bad, it just is. For example, the Surefire L2 and L4.

But as long as your light is making you happy, who cares who else lists other specs. I mean, I'm happy with my HDS even though you can buy a Surefire U2 knockoff for WAY less money that is WAY brighter. HDS does what I need it to do.

 

[p97z]

The DiNotte 5w bike light is a really nice light. They claim 120 lumens and it seems like it's brighter to be honest. I don't think they are overstating at all. The beam pattern is perfect for a handle bar light. The DiNotte 5w makes a perfect flood and works great with a P1D-CE on the helmet. When it comes to cycling the beam pattern is more important then lumens. A bright spot focused down the road doesn't help see a pot hole 10 feet in front of your tire.

 

[cratz2]

Yeah... what Bernie and 270 said...

Discounting beam shapes, effeciency, runtime and outright lies, think of it like this. You and I both design two different flashlights (we each design one) and market them. When I do my testing on the finished product, I determine that of 100 lights, they range from 102 to 124 Lumens. I advertise it as a 100 Lumen light. You test your lights and find that they range from 88 to 121 Lumens and since you market your lights to a more fickle market, you decide to call your light 120 Lumens.

Neither of us have lied. And both of our lights are quite possibly excellent tools. But because of marketing decisions, we spec'd them differently.

Then you end up with a bunch of folks on CPF wondering which of our lights is brighter.

 

[cratz2]

One good thing about bike lights though is since they are generally moving when being used, heat build up is less of an issue.

Personally, I prefer a wider beam on a bike than a super thin but intense beam. Obviously it would come down to individual lights, but other than runtime issues, I'd tend to think that Lux Vs would make better 'perfect' bike lights than Crees, SSCs or Lux IIIs.

 

[270winchester]

the nice thing about the newer LEDs such as the Seoul adn the Cree is the small size of the die make them easier to focus in small lights, so you can have HD45-like beam in an HDS sized light whereas before you are stuck with a flood beam in a small package.

the fact that they are a lot more efficient does not hurt, plus they are cheaper to make than Lux Vs. As far as sheer lumen count goes though, the Lux V is still relevant, as of now.

 

[woodrow]

It would be really nice if manufactures were actually honest about their lumans ratings. Also it would be nice if actual torch lumans was the standard. One really does have to praise Surefire for being honest and even underating output level of their lights.

 

[2xTrinity]

It would be really nice if manufactures were actually honest about their lumans ratings. Also it would be nice if actual torch lumans was the standard. One really does have to praise Surefire for being honest and even underating output level of their lights.

Well, the only way I see this happening is a standardized third party lab testing, similar to how light bulbs are tested. Since there are no sorts of regulations with respect to flashlgihts though, don't expect to ever see such a thing. The best we can probably do is look to websites like Flashlight Reviews (or vendors like Dealextreme that apparently test their lights using the same methodology as Flashlight Reviews) in order to have a standard to compare relative light ouptut from different brands.

 

[TORCH_BOY]

Some manufactures state the power of the LED and the Lumens rating of the Led which the light uses. eg 3watt MINIM@G 2 AA it has a 3 watt Luxeon 80 lumen Led, but in real life the light is only driving the led at 1.5 Watts, Same as Terralux, Fenix L1T ect.

 

[Outdoors Fanatic]

120 lumens is easy for a good Lux V. My old L5 was brighter than my P1D-CE (which actually puts out +/-110l, not 135l). Therefore, I don't think they are overstating anything-- as long as they are using a good bin LED driven at the right specs.

Don't forget that SureFire is the only manufacturer that underrate their lumens, so when they say a given product delivers 100 lumens, that's a guaranteed minimum, not the peak output or theorical output. A SF lux 5 like an L6 may very well be in the ballpark of 140 lumens.

 

[ken2400]

http://en.wikipedia.org/wiki/Luminous_efficacy
683 lm/W, corresponds to an efficiency of 100%.

I hope to see at least 50% 342.5 lm/W

 

[2xTrinity]

http://en.wikipedia.org/wiki/Luminous_efficacy
683 lm/W, corresponds to an efficiency of 100%.

I hope to see at least 50% 342.5 lm/W

I hope you also like working under monochromatic lime green light

 

[socalrunner]

Thanks for all the input.. I compared my L2D-CE to the 3 watt ultra version at the same mode to give similar output of stated 80 lumens and by far the L2D was brighter..

http://www.dinottelighting.com/DiNotte_Lighting_Ultra_3.htm

What about the price difference I keep saying to him.. 169 for a 3 watt luxeon and 199.00 for a 5 watt luxeon. He could buy 2 - L2D-ce's and 1- L1D-ce and be at the same overall price..

I told him if he was dead set on the Dinotte to wait and I am sure they will be migrating all there product to the Cree Technology. They have a new light coming out that is using a triple cree handlebar light called the 500L.

 

[M I K]

All I keep getting back is well 120 lumens is brighter than 90 lumens. Help my friend see the light because he needs some convincing..

Hey, don't worry about it. Just tell him to strap on whatever he thinks he needs and tell him to have a nice ride. He will be able to see just fine with either one, and he'll be happy.

 

[p97z]

Keep watching Nashbar.com for the DiNotte. They just sold of out the lithium 5W at 139.99 with free shipping. I haven't found a flashlight that can compare to the flood of the DiNotte 5w. I'm sure there is a flashlight that would work but not at the size of the DiNotte.

 

[selfbuilt]

120 lumens is easy for a good Lux V. My old L5 was brighter than my P1D-CE (which actually puts out +/-110l, not 135l).

Same here - my L2 on Hi has about ~10% more output than my P1DCE on Hi in my home-made lightbox. That would put my Lux V L2 at about 120 lumens, using Chevrofreak's 110 estimate for the P1DCE.

 

[Strauss]

Just to contribute to this thread, I have also tested my P1D-CE and Surefire L5 in my "home-made lightbox".

I got 110 lumens out of my P1D-CE on high. With my L5; on a single 17670 cell I got 110 lumens(runs for ~50min), and on 2xRCR123's I got 150 lumens(30min runtime).

I was able to hand pick my L5 locally, where they had a few to choose from. I turned them all on and the one I bought obviously had the best tint, and I feel like I won the "lottery". Only one of the L5's there did have a week, green tint to it, and was down on output. The others appeared just as bright, but were a bit blue-ish compared to mine. Mine has a nice milky-white tint.....

 

[socalrunner]

Keep watching Nashbar.com for the DiNotte. They just sold of out the lithium 5W at 139.99 with free shipping. I haven't found a flashlight that can compare to the flood of the DiNotte 5w. I'm sure there is a flashlight that would work but not at the size of the DiNotte.

I will let my friend know so he can save some money.. I am sure that dinotte and others will eventually switch to the Cree XR-E..