Does the surefire L4 have a doughnut hole?

I've heard rumors that the L4 has a doughnut hole; does it have a doughnut hole and if so how bad is it?

I depends on what you get. It is kinda like the luxeon lottery, some do, some don't. If you talk to sure fire youu may be able to return it for one that doesn't have one. I'm sure that there are some people here that have similar experiences

Mine has a negligible donut hole, meaning that on a white wall I can hardly tell that the middle is barely darker than the rest of the hot spot. Up close (say three inches or fewer) you can see the hole. I'd characterize it as virtually donut-hole free.

I'll say negligible on mine, too. I actually never notice it unless I'm trying really hard. I just checked, and I had to shine it on various walls until I could see it. I finally noticed it on a white door.

I have 2 L4's one has a very large donut hole and the other has absolutely no hole. In using both of them I can tell NO difference in the output.

Although in "testing" the one without a hole seems to be brighter.

I think the heads are getting brighter and better with time. There was a 6 month space between my purchases and the latest was about 2 weeks ago.

mine has a very slight dark spot. I don't worry about it. I would prefer the tint to be different. It has the light green tint and it bugs me a little. Not enough to send it back though. I love the TW4 configuration!! my EDC until I pull the trigger on a Mclux PD.....

Mine is always negligible. It is slightly noticeable only when shining on a wall. It is so common to find a doughnut hole for any LuxV lights. My Mag mod, PR head and SF-504 will find a doughnut too.

Just got a KL4 and was expecting a hole, but to be honest it's not got one worth mentioning, you can only see a slightly darker centre when you shine it on a wall.

It works great on a 1x123 vital gear body and a R123, and it gets nice and warm:devil:

Mark

Hey—aren't 'doughnut holes' sold at the local bakery where you can have them custard cream filled? He he he. . .

My L4 has an extremely even beam, and it has an off-center LED. A fortuitous flaw maybe.

Scott

My L4 has a very slight donut hole... but the thing is, the L4 has such a floody beam (the legendary "wall of light") that in real use, I would never notice it. It's not like there's a tight, distinct, donut-shaped hotspot or anything.

I have a good amount of experience with Surefire LEDS, i own a KL3, E2L, L6, L6, U2 and the one L4 i have tried out had the most noticeable and worst donut I have ever seen in a Surefire light, i know its the lottery, but im just giving you my experience and that L4 was worse than any LED donut I have ever seen.

I have 2, prolly a year or so old. Neither exhibits a hole, even 3" "point blanco." I wonder if later L4s have "later" LSs with different slugs. (Die height) I also wonder if the U2 issues are due to die height issues. :shrug:

Larry

Got one on the way, will post when I get it. mmmmmmmm donuts!!!

Yeah, I've messed with a butt load of KL4s and most do have the doughnut hole. Sometimes the doughnut hole disappears when you throw a new emitter in there. Since the newer "joker" luxeons have come out, I've been wondering if the newer Lux Vs also have the dies sitting a bit lower. If they do, this may be a fix for all of the lights that are exhibiting doughnut holes. I say this because I used to turn a .020" spacer to go between the reflector and the sink on my builds to space the luxeon out some to get rid of the doughnut hole.

On the other hand, the only SURE way to get rid of the doughnut hole is to replace the Lux V with a Lux III and run the light on a li-ion cell. If you over drive the converter to pump 1A to the LED, you really don't loose any overall light, but you do gain a bunch of throw. Of course you will loose some of the flood.