Surefire L5 Questions...

I'm looking at the Surefire L5 and wanting it for christmas and I was wondering.....Does it produce 120 Lumens for the entire life of the batteries or does it slowly diminish over time and then die like typical LED lights? I was just wondering if Surefire regulated the light in such a way as to keep pushing 120 Lumens out the front as opposed to let it slowly die over time. If it keeps 120 lumens for the course of the batteries then I'm sold.....

I have an L5. (Excellent light).

Never ran it long enough to find out that answer for myself.

But this should help....
http://www.flashlightreviews.com/reviews/surefire_l5.htm

BTW, not sure if you've physically examined one but; the head is HUGE, for a two cell light.

That link that you provided Monocrom was really informative. But it still doesn't answer my question on the lifetime of the 120 Lumens. Anybody else know??

The light won't put out 120 lumens for the full life of the batteries and then go completely dead, if that's what you're asking. It'll do full output for a specified time, the drop down to a much lower output level which it holds for a while. Also, if you're getting that output number from the most recent catalog, it won't refer to any L5 on the market because the updated version has not been released yet. The current L5 is rated at 100 lumens.

here's one runtime of the L5:

http://members.aol.com/qn9513/myhomepage/flashlightl5.html

I have an L5 and it runs for an hour at full output then once the batteries have been depleted to much you really notice a drop in output. It is regulated so it uses as much of the battery as possible to give you full power for at least an hour.
Hope that helps.....


What won't help is the compulsion you will feel to buy more lights after you get the L5. The L5 was my first Surefire. I bought it just over a year ago........since then I have bought over 15-20 Surefires. Some I have bought at great prices and given as gifts, others I have bought just to get a part I want and then part the rest of the light out. As of now I have 11. The ability to interchange different heads/bodies/tailcaps makes it interesting and upgradable!

DaFabricata....you've answered my question. Not quite what I was hoping for. But enough to make me want to buy it. I like the fact that Surefire regulated it to try too provide as many lumens as possible for as long as possible.

And as far as Surefire collections go...I already have a G2 and a 6P. This is hopefully going to be my third (or fourth Surefire as I would like to pick up a C2).

Thanks guys!! Any other info that I should be aware of?

When you notice that the L5 (KL5) has dropped in output, it is time to change out the batteries, as there is a pretty steep drop off. I run my KL5 in an 18650 body and when I notice reduced output, I switch out the 18650 battery. The drop off is very noticeable.

Bill

A bit unrelated, but consider getting an M2 instead of the C2. I own a Surefire C2. It was my first clip-carried tactical light. Works well. But I must admit that if I had to do it all over again, I'd go with the M2 for the extra high-output lamp and the shock isolated bezel. Both are excellent lights. But I feel the M2 is a bit better.

Ironically, now that I have my L5 and still have my C2; I'm not likely to get an M2.

Bullzeyebill said:

The drop off is very noticeable.

Bill

Click to expand...

Well put.

Was there ever any further update on a new L5? I was really excited about this light during the spring and then all of the sudden Surefire said it was a no-go. I've heard nothing new since then.

Wick said:

Was there ever any further update on a new L5? I was really excited about this light during the spring and then all of the sudden Surefire said it was a no-go. I've heard nothing new since then.

Click to expand...

Same here.

I don't own a L5, but I do have an L7, which is similar (it has a deeper dish reflector and is rechargeable). But from that point of view, I would say go for it because if the L7 is a great light (it is a bit heavy), I would think the L5 would be just as good, but on a side not, it will have a slightly wider beam than the L7.

I just found my copy of the Surefire 2007 Catalog and it's claiming 120 Lumens for 4.5 hours of runtime.....Now obviously that is not 120 lumens for the entire life of the batteries but it is a good enough run time for me. Another member replying to this thread had stated that Surefire didn't release this improved L5 as of yet? Or am I misunderstanding said poster? I hope that Surefire has...because I want one!!! Thanks!!

No misunderstanding. The specs shown in the 2007 catalog do not refer to any L5 currently on the market. The most I know is that the Cree L5 is on "indefinite hold." I'm sure there are CPF members with more information, but they may not be able to tell us anything at this point.

I have ran mine from a fresh set of batteries until it is very dim. Here is a break down.

full brightness (no dimming): 1hr 12 minutes, hot but not like L4 hot.
sharp step down (about half as bright within 3 seconds): run for another 30 min before...
another step down (very little light, say about 10 lumen-ish): 20 min.

The thing about the higher end Surefire lights is you get better regulation and heat management. The new 6PL and G2 gets a blast in brightness but it only lasts a few minutes and then it starts to dim (due to poor heat management). L6, L5, L4, and E2L's (Cree and Luxeons) all perform at pretty steady output (no dimming for the life of the batteries). The thing about lithiums is it also puts out a constant current for 95% of it's life, so voltage and current drop only occurs when batteries are nearly exhausted.

By the way, the new E2L-Cree gets a flat airport runway MAXX output for 9 hrs., then 5 hrs. of continuous step down dimming.:devil::devil::devil:

Thanks entrekman. This is more or less what I was looking for. I didn't want to buy the light and then have start losing brightness immediately. I want it to last for as long as possible. And thanks for the lithium battery trivia. I didn't know that they worked in such a way.

Trivia, Oh my GOD! Lithium battery trivia? This is cutting edge stuff here. I am not using CR123's with my KL5, and I get awesome runtime with excellent light output. Just kidding. I am not really upset, but..................

Bill

BullzeyeBill....I'm confused by your reply.....Huh? Yeah I said trivia...because that is what it is to me....I'm new to all of this and would love to learn more......and I'm guessing that the way lithium batteries work is just a tip of the iceberg. So could you please explain your reply to me? Because I'm really sitting here scratching my head...

exoduster18 said:

BullzeyeBill....I'm confused by your reply.....Huh? Yeah I said trivia...because that is what it is to me....I'm new to all of this and would love to learn more......and I'm guessing that the way lithium batteries work is just a tip of the iceberg. So could you please explain your reply to me? Because I'm really sitting here scratching my head...

Click to expand...

The word Trivia means insignificant or inessential matters, and people would assume that you didn't really care for the battery info. Better choices of words would probably be data, knowledge, fact, etc. I knew what you meant so I didn't bother, but since Bullzeyebill brought it up, I might as well do some corrections.