L2 100 lumens but U2 only has 80?

why does the lower model L2 have more lumens than the high end U2?

also I have already ordered my U2 should be here tommorow i'll let eveyone know if i won the led lottery.

but wanted to know a couple quick questions

1. if I have the light on it's highest setting and turn it off and turn it back on will it stay on the highest setting or return to a lower setting?

2. am i correct that an aleph III head can be used without modification on the U2 to aqquire a longer throw?

thanks again guys don't know where i would be with out all of your help.

hate havin to keep buggin ppl

Troy

1 should stay at whatever setting the selector ring is positioned at.
2 I think the U2 is based on the bigger series of SF lights like the 6P, etc. The Aleph series is for the e series SF's. You could get a SF KL3 (pencil beam, no sidespill) for runtime and super throw though.

The L2 I think is rechargable and probably drives the LED a bit harder, or it's just marketing inconsistancies. Compare them both and see if you notice a big difference...

Troy, ya beat me to it! I was just on the SF page looking at lights...
I was wondering why the L2 was the brightest LED they were listing (that wasn't made of unobtanium!) and was not the most expensive...If I could scrounge an L2 on the cheap, I'd be a happy camper!
--Vic

lumen ratings mean very little. luxeon lottery will decide final output.

my U2 is way brighter than my L2. your mileage may veri

vic303 said:

Troy, ya beat me to it! I was just on the SF page looking at lights...
I was wondering why the L2 was the brightest LED they were listing (that wasn't made of unobtanium!) and was not the most expensive...If I could scrounge an L2 on the cheap, I'd be a happy camper!
--Vic

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You have to remeber that it only takes 11 minutes to drop from 100 lumens to 50 lumens...

thanks isaac i'll be looking into the KL3 now

cy very true about the lottery thanks for the reminder.

hog very good point never took that into consideration at how fast it eats through batterys and drops down in lumens compared.

thanks everyone for the quick responses

hogx1 said:

You have to remeber that it only takes 11 minutes to drop from 100 lumens to 50 lumens...

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No one else is seeing that problem as such we are starting to discount it as a witness of thermal protection, not a lack of good regulation.

As for the U2's out put. I trust the 100lumens number that is printed on my box over the numbers seen on the web site. My u2 puts out about 20% more than my L2 and another U2 has been IS tested at 113lumen. Even so, the differences aren't stark, the pattern of the the beam is.

The U2 has more THROW than the L2 and still has
a decent flood. .... :candle:

lightmeup81 said:

why does the lower model L2 have more lumens than the high end U2?...

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Surefire's published lumen numbers for the U2 vary: sometimes 80, sometimes 100. As previously stated, there's significant variation based on the Luxeon lottery.

Based on lux meter wall/ceiling reflection tests and comparing to my HDS EDC U60 (which should be calibrated to 60 lumens) My U2 puts out at least twice that much, which conservatively puts it at 100+ lumens.

My U2 equals or slightly out does my M2 with a P61 assy(120 lumens). That is my impression, it is at least very close to that. I have an old 8X rechargable that is rated at 110 lumens. My U2 equals that easily. I have an old 9N rechargable rated at 140 lumens. It is somewhat brighter than the U2, but not much. I like the U2 better than all the above lights, but of course they will all do in a pinch.

As said above the Luxeon Lottery has a part and also how hard the LED is being driven.

Any news on your U2?

1. The place of the selector ring right behind the head will determine what brightness it will be at.

2. No. the Aleph head works with the E series not the U2. Looking at my U2, the threads are on the head, not the body.

I compared the L2 vs U2 (multiple of each) and they are two different animals. The L2 has a wall of light while the U2 has more throw (based on lux readings, the L2 I have on hand on fresh batteries is ~616 lux and my U2 is ~1800 lux.)

I did a runtime test of the L2 based upon usage (L2 is meant to be used on low with a option for high for a short period of time because on high the LED is being driven at ~1.4-1.5 amps) here.

Jason

I wouldn't buy a U2 right now, even if I had that kind of disposable income available...I've read too many posts here in CPF about problems with the U2. As for the L2 only lasting 11min, I read the flashlightreviews.com post on it, and immediately got the impression that they had a defective unit. I kinda doubt that Surefire would be able to get away with a horribly exaggerated claim of 1hr/high runtime if in fact, 11min was the norm.

Possibly referring to the continuous runtime on the highest output before dipping down. Surely not the total runtime. After leaving it off for awhile, then using it when on high, it's still noticeably bright, even if only for a little while, you still have more than enough light for whatever task is at hand.

the two U2's that I'm selling over @:

https://www.candlepowerforums.com/threads/101818

both say 2-100 lumens

just out of curiosity is there an actual diffrence between the the U2 i ordered which the guy said 2-80lumens and the boxes that say 2-100 or are they just in the process of updating the boxes?

p.s. anyone know of a well known electronics store that i can pick up a light meter at? im in nw indiana if it is any help.

thanks
Troy

lightmeup81 said:

just out of curiosity is there an actual diffrence between the the U2 i ordered which the guy said 2-80lumens and the boxes that say 2-100 or are they just in the process of updating the boxes?Troy

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I'd tend to trust the box because it is printed (so a legal issue possibly) and any major deviation would subject Surefire to the ridicule that they put on the other companies who boast inflated numbers.

Luna said:

I'd tend to trust the box because it is printed (so a legal issue possibly) and any major deviation would subject Surefire to the ridicule that they put on the other companies who boast inflated numbers.

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I think the light has not changed, but due to the Luxeon Lottery, some U2s did not meet the original spec, so Surefire lowered the advertised output to make sure they did not misrepresent. This has been hashed over many times in the past, though it can be hard to find the threads because of the change in BB software.

wasBlinded said:

I think the light has not changed, but due to the Luxeon Lottery, some U2s did not meet the original spec, so Surefire lowered the advertised output to make sure they did not misrepresent. This has been hashed over many times in the past, though it can be hard to find the threads because of the change in BB software.

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I was present in those discussions but I haven't seen anything but conjecture as to why. (maybe we can get Al or one of the insiders to ask about this and the L2 having thermal protection) Every box I've seen shows 2-100 (they may exist showing 2-80 I just haven't seen them). Do the ones with the new plastic tubes show 80 or 100 on the box?

i think 80

Mine is AO8725, haas 3 sided body and plastic tube. Box said 2 - 100. Got it direct from Surefire beginning of this month.