Why No Cree or Seoul Lights With A Really Low Setting????

cslinger

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Is there some kind of issue with getting these LEDs to run in a very low mode such as .5 lumen-1 lumen? I find these low settings very useful from time to time but it seems that all the Cree/Seoul lights coming out have a low setting that is like 7-10 lumens which is actually pretty darn bring all things considered. Heck a few years ago 10 lumens out of a 1 AA light would have been downright impressive.

So why can we not get a nice three to four level CREE/Seoul light with spacing something like.....

Level 1 - LOW - .5-1 lumen. (100-300 hours)
Level 2 - LOW MID - 5-10 lumens. (15-40 hours)
Level 3 - HIGH - 40-60 lumens. (1.5-2.5 hours)
Level 4 - Turbo - 80-100 lumens. (30-50 minutes)

Shouldn't the above be possible with a quality lithium battery? Do these new LEDs have a limitation on how dim they can be?

Here is hoping the new EDCs from Novatac will retain their low levels.
 
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Grubbster

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Re: Why Now Cree or Seoul Lights With A Really Low Setting????

My HDS modded with a SSC will go very low. I believe the original emitter would do either 0.8 or 0.08, can't remember which. It doesn't seem like the new emitter is much if any brighter on that setting. On max the difference in the emitter is very noticeable. The new ones should be able to do the same.
 

RonM

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Re: Why Now Cree or Seoul Lights With A Really Low Setting????

I love the Fenix L0D-CE, but if I could have one change it would be an even lower low. Not so much to get more runtime, but for reading menus at restaurants and such. I too wonder why they didn't implement that. Maybe outside the range of the PWM circuit.
 

Cydonia

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Yes I hear ya. Very low mode and extended run time is essential in whatever future light I decide to buy. (No reverse clicky switches or twist multi-position bezel switches either. Flick the light off and on with clicky switch to enter different modes!)
 

johnny13oi

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FASTCAR said:
Ok I have 2 ask...who in gods name wants or needs .5 lumens?

How much light does a 5mm LED put out. I have one of those 7 led headlamps that is exactly like the streamlight septor and with one led one, it puts out a decent amount of light in total darkness
 

zifnab69

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hello,
i've got a gladius moded by icarus with ssc p4 and the low setting is very very low
i thing something like 1 or 2 lumens. ( original is 0.8 lumens)
Very grate mod....
 

Martini

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An XR-E or P4 putting out .5 lumens on PWM would simply be an ultra-dim strobe light. Remember this: the current generation of power LEDs use roughly half the current that the previous generation did to produce the same amount of light. In terms of PWM, that means about half the on-time. Now, with constant-current drivers, there shouldn't be an issue. I think that as things play out, manufacturers will get over the gee-whiz factor and start focusing on what is useful rather than what is impressive.

Regarding the usefulness of .5 lumens, there are plenty of HDS devotees that found a use for the EDC line's .08 lumen setting, so .5 is not that much of a stretch.
 

2xTrinity

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How much light does a 5mm LED put out. I have one of those 7 led headlamps that is exactly like the streamlight septor and with one led one, it puts out a decent amount of light in total darkness
Some of the best ones put out as much 80 lumens per watt, or around 6 lumens at rate current (20mA). A tenth of that wouldn't be especially useful. Some of the overdriven DX coincell lights I have, that I dropped higher efficiency LEDs into I estimate push over 12 lumens for burst. For extremely low output, I'd recommend a highly efficient white LED, with a CR2032 battery. About 2-3 lumens, <10mA, should last for several hours. Attaching one to a higher output light (to aid in battery changing etc) may not be a bad idea.
 

TORCH_BOY

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The driver circuits need a certain amount of power to run before they become efficient.
The fenix has done a good job of maintaining this with the L1D/L2D CE
 

Kilovolt

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My new Lumapower M3 on low gives out barely enough light to go to the kitchen for a glass of water during the night. I believe that actual lumen figures have not been published yet, but this flashlight's output on low is around 0.3 W which IMO is enough for reading a map but not necessarily for walking around.

As a comparison I may say that the output is much much less than an L0D CE or a U2 at their lowest settings. As a matter of fact I am not using the M3 for fetching water during the night because I tend to walk barefooted....and I hate hurting my toes......:)
 

Flight_Deck

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The Free.Light Spartanian has a VERY low low, and an excellent light overall! Not to mention the lowest setting on the Fenix LOD CE. But I agree that there needs to be more VERY low settings available as well - great for checking on the kids while they sleep.
 

MikeSalt

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I'm guessing it is due to the power supplies not evolving at the same rate as LED efficiency. Let us compare the P1D and P1D-CE. To avoid having to re-design a new power supply, Fenix simply used the original one for the *-CE. Now, low in the P1D may have been more than enough for most people, however, the Cree is almost twice as efficient as the Luxeon. So, on that same power supply, it is far too bright for some people. Ideally, new power suppiles (converter circuits) would be designed for each generation LED, but these extra costs would have to be passed on to us, the consumer.
 

ringzero

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FASTCAR said:
Ok I have 2 ask...who in gods name wants or needs .5 lumens?

I do. Getting up late at night, anything over about 1 lumen dazzles my eyes. Half a lumen is about ideal for my trips to the kitchen or bathroom late at night.

I use a dual-level Streamlight TaskLight 1AA with 1 lumen low and 5 lumen high levels. This is a great late night, inside the house light. Runs over 50 hours on low level.

Have discovered that I like this light even better with a nearly depleted cell, because the levels are more like 0.5 lumen and 2.5 lumen. So I never put in a fresh cell, but always recycle AA cells that have already been used in another light.


.
 

flashy bazook

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first, I agree with kilovolt. The M3 has a pretty low LO setting - and as he says we don't have measurements but it seems close to as low it can be and still be useful for getting around. I find the L1D CE setting on LO also to be sufficiently low (I believe at 8 lumens by flashlight reviews data).

If you really need 1 lumen or 0.5 lumen low, there is one really easy solution, which is to have those tiny LED keychain lights you can buy at one of those big home-supply stores with you in addition to your regular flashlight. They last for a loong time and you can buy several at a time.

Right now I have the SF L1 1st gen red light output for the really low output but I find I don't really use it much in that mode.
 

NetKidz

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Not sure about the lumen reading, but my LF2's lowest level (0.2%) is about 1 lux @1m for NiMH battery and 3 lux @1m for 10440 Li-ion rechargeable. :)
 

Long John

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You can go the custom-way and look fo a light with a Flupic-board.

It's a very nice driver with user-setable brightness levels. 5 different modes with all solutions you like.
I prefer mode 1 with low (setable between 1 very dim - 10 very bright), med (same potential) and high (brightest).:twothumbs

Best regards

_____
Tom
 

aceo07

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I have my U60, upgraded with Seoul, set to about 0.5lumens for my low setting. It's great for reading in the dark.
 
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