Why do people say the Surefire L2 is meant to be used on low?

fire-stick

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I've read a few post that say the L2 is meant to be used on low and high is meant to be used as a momentary high/"boost"..

What's the main reason behind this?

I hardly use any of my "powerful lights" longer than a minute or two. Mainly just to check the driveway as I pull in on my bike or check the yard for anything or anyone that might be lurking around.

Would it be alright to just use this light for its high mode for short bursts?
 

thk

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Bleh. Use it any way you deem fit. I wouldn't worry about it. Use it on max all the time if you need to. Never read that about the L2 before.
 

lightplay22

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I think the reason is to extend battery life. If the low setting produces enough illumination for your needs and the high setting is only used intermittently, you will get much greater battery life than just using the high setting continuously.
 

dizzy

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I use my L2 on high continuously when out walking at night with no problems at all. It's probably my favorite nighttime walk light because of the huge amount of flood it provides, no need to pan back and forth so others can see well. My $.02:)
 

Spade

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I love the L2. I use it mostly on low to conserve batteries. I use high for boost when I need it, or just to remember how dang bright the thing is. I tend to get a lot of life out of my batteries.

S
 

270winchester

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I think is was Al that said to think of L2 as a utilitarian light with a regulated output with high output rather than a high output light with a low level. THe High is not regulated whereas the low is, and from what I have seen the low provides enough light for 90% of the stuff I do in the wilderness.
 

jar3ds

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just use it!

If you have the newer model you'll have about 30min of regulation....
 

SCblur

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270winchester said:
I think is was Al that said to think of L2 as a utilitarian light with a regulated output with high output rather than a high output light with a low level. THe High is not regulated whereas the low is, and from what I have seen the low provides enough light for 90% of the stuff I do in the wilderness.

actually, the high mode is regulated. see graph here:
http://www.obaq.tv/cpf/images/SureFire_L2_L4_Runtime.png
 

270winchester

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SCblur said:
actually, the high mode is regulated. see graph here:
http://www.obaq.tv/cpf/images/SureFire_L2_L4_Runtime.png

Al was referring to the first generation L2 I believe, which even in the best case senerio has a sloping curve that suggested it as being not completely regulated.

I decided not to buy a L2 because of its incompatibility with the Pila 168s, which fits nicely in the L4.
 
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SCblur

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The L2 tested in that graph is the older version. I think the problem w/ the regulation is that the L2 overheats when unattended and the output curve slopes off. In the graph I linked to, he was cooling the L2 w/ a fan and it did much better, almost as good as the L4. I have had similar results w/ my L2. When I have turned it on and left it alone it drops to noticeably low levels in about 30 minutes. However, I have taken the same L2 hiking at night and gotten a solid hour with absolutely no perceivable decrease in output to my eyes. The only difference is I had the L2 outside and I was holding it the whole time, helping to dissipate heat away from the head. When I let my L2 sit on the other hand, it will literally get too hot to touch in a very short period of time.
 
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Size15's

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I use an L2 as my primary EDC and find that if I have the mindset that it is a low output flashlight with a high output mode (rather than the otherway around) I tend to use the low output first and if it's bright enough I don't go to the high otuput. I used to approach it the other way around but found I didn't often choose to reduce the output and used batteries much faster as a result.
 

fire-stick

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I was planning on getting a KL-3 for my C3 but now I'm thinking about just saving up and getting a seperate LED light. I was thinking maybe an L2 or an L4.

So on the L2's low can it be used in constant on, or is the low just momentary?

If I buy an L2 how do I tell the newer version from the old version?
 

SCblur

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either mode can be used in constant-on.

the older version has four flat sides on the body, the newer version is a tiny bit longer, and has three rounded sides.
 
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