Some Q about L2.

Oh well, I went ahead and pruchase the new version round body L2. I notice the following.

1) The tint in Low and High seems to be different. On low it has a green/yellow tint, but on high it in pure white.

2) On high, there is a hole in the middle when I shine the light about 2m away on a white wall. Do you guys have the same phenomenon with your L2. In addition, the "hole" in the middle seems to bear the tint 'carried' forward from the low beam. Which means ,on high beam, I see a white beam on the outer hot spot and small dim greenish tint in the centre of the hotspot. Sort of a mixed tint. Is this consider as a 'defect'? Anyone have a L2 that shine uniform tinted high beam?

3) Is the head a KL4?


TIA.

I would agree with you on both accounts. I have a hole in both low and high though. The hole is pretty faint and I really only notice it if I shine it close against a white wall. The difference in tint may just may be a matter of physics with LEDs, since you are not really giving the LED enough juice to show it's true tint. Just a guess, but I don't think it is a Surefire defect.

a white LED will always be more green the dimmer it gets, and more blue the brighter it gets. the only way to mitigate this effect is pulse wave modulation /ubbthreads/images/graemlins/smile.gif

And man! I had compared the brightness...My L2's output (on high) is much brighter than my L6. Can really tell the difference! It smokes the L6!!! What a shame, my L6... Beaten hands down to a smaller brother. Should I sell it?

pulse wave modulation? how do I go about doing it? /ubbthreads/images/graemlins/smile.gif


[ QUOTE ]
chamenos said:
a white LED will always be more green the dimmer it gets, and more blue the brighter it gets. the only way to mitigate this effect is pulse wave modulation /ubbthreads/images/graemlins/smile.gif

[/ QUOTE ]

I bought a new L2 two weeks ago. It does the same thing.

I don't know if the head is a KL4 (I don't know much about the different Surefire LED heads).


[ QUOTE ]
Hoya said:
Oh well, I went ahead and pruchase the new version round body L2. I notice the following.

1) The tint in Low and High seems to be different. On low it has a green/yellow tint, but on high it in pure white.

2) On high, there is a hole in the middle when I shine the light about 2m away on a white wall. Do you guys have the same phenomenon with your L2. In addition, the "hole" in the middle seems to bear the tint 'carried' forward from the low beam. Which means ,on high beam, I see a white beam on the outer hot spot and small dim greenish tint in the centre of the hotspot. Sort of a mixed tint. Is this consider as a 'defect'? Anyone have a L2 that shine uniform tinted high beam?

3) Is the head a KL4?


TIA.

[/ QUOTE ]

Hoya,
Your observations are most CPFers' experience with the L2. I think the color differences and the doughnut hole will only bug you on a white wall. Take it out in the woods at night and you'll come to appreciate the light for what it is. If you have second thoughts about your purchase, hang on to it for a little while, its usefullness will really grow on you. /ubbthreads/images/graemlins/cool.gif

The L2's bezel is not the same as the KL4 bezel.
The KL4 contains the electronics.
The L2's electronics are contained within the body.

I'm on my second L2. They both showed the same traits as yours but with a "brown" tint in the middle on Lo and Hi and my latest one was also a good bit dimmer than my KL4 (on 2 cells).
The first one was sent back to SF and returned to spec/replaced. I've just sent my new one over too.
I think for the money,these should be a good deal better. I thought the first one being faulty was a fluke.It seems it's not.
A great light if you get a good one or have it go through QA a second time!

hoya: pulse wave modulation is something that switches the LED on and off at the brightest possible level, such that the output averages out to be the same as driving it at a constant lower current, albeit without the shift in tint that happens when the LED is driven at a lower current. PWM has to be designed into the LED's driver electronics, and isn't something you can just add-on. but like leukos said, it isn't really that noticeable when you use it /ubbthreads/images/graemlins/smile.gif

phil_b: sorry to hear about your L2s...i've had bad luck with some of my surefires, but i lucked on the L1 i just bought; snow-white, bright, beam that's centred and it doesn't leak through the lens! surefires are great when they don't get messed up by poor QC /ubbthreads/images/graemlins/grin.gif

Hoya, my L2 shows the same thing. It does have a slightly green hue on the low setting, but is very white on the high. I never really paid attention to it until I compared it to other lights, but it's not enough of an issue to be worried about.

[ QUOTE ]
Hoya said:
And man! I had compared the brightness...My L2's output (on high) is much brighter than my L6. Can really tell the difference! It smokes the L6!!! What a shame, my L6... Beaten hands down to a smaller brother. Should I sell it?

[/ QUOTE ]
I would sell it, that is for sure.. Can't have a big light light that laying around getting beaten up by a L2..
Tell ya what.. Not only will I take that thing off your hands But I'll even pay for the shipping.. /ubbthreads/images/graemlins/wink.gif
Is it really that much brighter? How about the throw? They are the same LED only one is driven by 6v and is meant more for a bit of throw..
Shoot me a pm about your L6, I may be able to alleviate your discomfort.. /ubbthreads/images/graemlins/smile.gif
Enjoy the L2, I hear it is a great light!

If this is the case, then do you mean you will get different tint from SF U2 for all the light levels? I haven't got the U2 yet, but I'll be more careful to compare the beam from level 1-6 before I take it. It broke my heart that day when I saw another L2 with a bluer tinted low beam... Hmm...Does SF really have a QA dept? I wonder.



[ QUOTE ]
chamenos said:
a white LED will always be more green the dimmer it gets, and more blue the brighter it gets. the only way to mitigate this effect is pulse wave modulation /ubbthreads/images/graemlins/smile.gif

[/ QUOTE ]

Pydpiper, thnks for the offer. I think I'll keep the L6, it is a beautiful light. Though it may not be as bright as the L2, it throws considerably further. I might get the KT4 to turn it into a throw monster /ubbthreads/images/graemlins/wink.gif


quote]Pydpiper said:
[ QUOTE ]
Hoya said:
And man! I had compared the brightness...My L2's output (on high) is much brighter than my L6. Can really tell the difference! It smokes the L6!!! What a shame, my L6... Beaten hands down to a smaller brother. Should I sell it?

[/ QUOTE ]
I would sell it, that is for sure.. Can't have a big light light that laying around getting beaten up by a L2..
Tell ya what.. Not only will I take that thing off your hands But I'll even pay for the shipping.. /ubbthreads/images/graemlins/wink.gif
Is it really that much brighter? How about the throw? They are the same LED only one is driven by 6v and is meant more for a bit of throw..
Shoot me a pm about your L6, I may be able to alleviate your discomfort.. /ubbthreads/images/graemlins/smile.gif
Enjoy the L2, I hear it is a great light!

[/ QUOTE ]