Cree XR-E: Twice as Bright or Twice the Runtime?

I'm with you on the runtime...

I think the nicest thing with the new Cree's is the efficiency to get more runtime. Basically, find a flashlight you like with the amount of brightness that you like as well. Make this model now with a Cree and it instantly gives more runtime - kinda like getting more light for free.

I posted my thread below. My perfect EDC upgrade is the form factor of the AAA light (I like the style of the Jetbeam AAA and LOP) with flat regulation of 4-5 hours on a Lithium cell. A low and high setting are nice but not as important to me. A simple 2-stage is prefered with a low giving 10 hours.

Bearcat said:

Am I in the minority in thinking that the real advantage of the XR-E is twice the runtime? I would be tickled to death to have a small 1- AAA keychain light with a XR-E LED that had the same light levels as my new Safe-Light I got from Wits-End. Do any of you flashlight gurus know what the runtimes would be for such a light?

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The real advantage is that the LED is more efficient. Do with it what you like. With the explosion of affordable multi-level lights, brightness and runtime can coexist in the same package.

Twice the runtime. Crees are not twice as bright as Luxeon Vs.

Bearcat said:

Am I in the minority in thinking that the real advantage of the XR-E is twice the runtime? ...

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No, you are not alone in liking lights with good efficiency. All the lights I really like have good efficiency for their level of brightness.

Outdoors Fanatic said:

Twice the runtime. Crees are not twice as bright as Luxeon Vs.

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True, but now we can get the output of a Luxeon V with the focusability of a Luxeon III (and twice the Lux V runtime and half of the heat load). It's twice the output of the Luxeon III, which is Luxeon with the highest output that can also be focused well.

I always considered the Luxeon V to be a limited-use product due to its large die size, although a few flashlights (like the Surefire L5) make good use of the Lux V despite its limitations.

To a point, I don't really care about efficiency. That's what they make rechargeable or extra batteries for. I want as bright as possible, (without doing damage to the LED).

I love the idea that these new Next gen emitters have the overhead to be as bright or brighter than the "standard" Lux III emitters while improving upon run times.
I have a Mc ????PD coming with a Seoul P4 U-Bin part which will run as bright as my LUX III based light on much less power.
This is a bright light with great runtime. The best of both worlds.

Soon we will have even brighter lights with great runtime!!
I want both.

Yaesumofo

I want both... ~140 lumens on high with ~12 lumens on low would be the bomb...

InfidelCastro said:

To a point, I don't really care about efficiency. That's what they make rechargeable or extra batteries for. I want as bright as possible, (without doing damage to the LED).

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So in other words, you'd take the tradeoff of giving up runtime to gain extra brightness. One major point worth noting is that the added efficiency has an additional benefit even beside brighter light at the same power, or longer runtime at the same output. More electrical energy is being emitted as light, rather than forming waste heat in the LED. Because less waste heat is being produced, assuming the same heat tolerance, it should be possible to either concentrate the same amount of light into a smaller die for more throw, or increase the power while keeping temperature constant.

I'll go alone with less heat with Cree. My CM Cree modded KL6 at 1 amp to the led runs cool, whereas my KL6 with the lux V ran fairly hot, and a WxxS modded to that same KL6, at 1 amp to led, was really hot, and you could watch the output drop, drop, drop (bounce with lightmeter). The Cree at one amp is 15% brighter, barely getting a little warm and holds its output like a rock.

Bill

Bearcat said:

I wonder how bright a 1-AAA Cree XR-E keychain light would be with a 10 hour runtime that is fully regulated. Would that be like a Fenix EO that is four times as bright?

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I had to use a twice as bright Cree XR-E to read the small font.

How about twice the runtime of my P1, with a boost of even more light on demand?

I'm looking to acquire a Jetbeam 1AA Cree. I've never even had a multi level light before (well, unless you count 5MM stuff).

But frankly, I've never found my P1 TOO bright as a work EDC. I'd be less inclined to use it around the house. That seems to scream for multi levels!

Surely, with a light with 2 or more levels you can have both.

More runtime on a lower level at the same brightness as before with
a luxeon, or more brightness at a higher level with the same runtime
as before.

Why should these be contradictory?

Better run time is nice, but I prefer brighter output. I can easily carry some extra batteries, but there's nothing I can do about maximum brightness.

I guess that I am just survival minded, because long runtimes interest me more than brightness does. I just can not see having more than twice the light that is needed at the expense of runtime. Just recently I gave a friend of mine a Safe-Light that I ordered from Wits-End. When I asked him if it was enough light to find his way through the woods in the dark to his deer stand, he stated that he only used the low setting, because the high setting was more light than he needed to find his way and he did not want to spook any deer.

I am just curious, what specific need is there for a 1-AAA keychain light to be much brighter than say the Safe-Light on its highest setting that would warrant a shorter runtime?

Bearcat said:

I wonder how bright a 1-AAA Cree XR-E keychain light would be with a 10 hour runtime that is fully regulated. Would that be like a Fenix EO that is four times as bright?

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I can only read this while in edit mode. Might want to try a larger font.

InfidelCastro said:

I can only read this while in edit mode. Might want to try a larger font.

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I do not know what the heck is going on with my fonts. I am using Verdana #2. What should I use?

Most browsers let you zoom text if it's too small to read.
Usually its Control-+ (Command-+ on a Mac).