I posted a response to a thread on another forum (hint…rymes with barf) to the question in the title.
I responded with a good rule of thumb is:
2 lumens per yard to IDENTIFY
1 lumen per yard to OBSERVE
Example: 120 lumens would give you aprox 60 yards to identify a target and be able to engage that target with cerntainty and aprox 120 yards of light to observe a target only.
This was the rule of thumb given to me at a low light/no light class taught by LMS Defense.
One of the responses I got was…that I was an idiot and didn’t know what I was talking about. I brushed it off and didn’t even respond as I trust my source.
So what say you, what do you consider enough lumens?
ETA: Assuming these are tactical weapon mounted lights. I assume most tactical oriented lights are going to have similar beam profiles given their intended use.
Depends entirely on the beam profile. 120 decently focused lumens can work very well. 120 floody lumens are useless for anything except looking for scorpions in the garden. Lumens just measures total output out the front, it doesn’t account for the beam profile.
this may be technically correct but it does little to advance the discussion.
as far as someone having gone so far as to quantify lumens, if they have some rationale behind their opinion, I might be willing to accept it until I or someone else proves otherwise.
as for how much is “enough”, I don’t know but some folks have claimed the 65 lumens of the SF incandescent is all you need indoors and that too much light is not beneficial. I can understand their argument , however, speaking only from personal experience, I’ve never felt the need for “less” light (except for close detail use), so my answer would have to be the more the better. referring back to your statement I prefer a “floody” profile with lots of lumens to brighten the spill.
the Streamlight TLR 1s with its 160 lumens should be an improvement in throw over the TLR @135 lumens but at the expense of a tighter hotspot and spill. I have both and the difference is mostly academic.
I think that this may need to be narrowed down a bit…
Are you talking about a weapon mounted light? If so, in my opinion, a super bright cornea burning light is not necessary. Weapon mounted lights are solely for identifying a target before engaging it (or not engaging it). You are not supposed to “search” for a target with your weapon light. All of my rifles are equipped with Surefire G2 lights on VTac mounts. They work for me and are quality lights. The price is right too. I have TLR1s lights on my handguns. Again, they work for me and the price is right.
If you are talking about a hand held light to search for people or items than I believe that your original statement is spot on.
Remember, when you are in a situation where you are searching for a bad guy in the dark, night vision (natural not electronic) and the ability to not give away your position are more important than how super bright your light is.
This contributes A LOT to the discussion, and I’m not sure why ra2bach feels otherwise.
I had a Fenix TK35 which uses and Cree XM-L and puts out 800+ lumens, but other lights I’ve had which use smaller, less powerful emitters in deeper more focused reflectors threw light further. I think flood/spill vs. throw is a far more important factor to consider when picking a light for a certain application than lumen output.
A high lumen (300+), floody beam is great for searching outdoors in a tightly packed neighborhood, but worthless in a more open area where a light with lower lumens but a tighter reflector would rule. And neither one of those lights would be ideal indoors. Ambient light plays into all of this as well.
To me, the most well rounded type of light is one where there is a primary switch for on and off, and a separate switch or mode ring for changing brightness. That way, you can adjust ahead of time if you know if you are going to be inside or outside, but there are no worries about having to cycle through modes to get to what you want.
That said, for work (patrol cop) I tend to stick with single mode lights for simplicity. And when stuck with only one mode, I would rather deal with the disadvantages of light that is TOO bright for certain situations than a light which isn’t bright enough. If I wash out my vision with too much light, I can generally rest assured that anyone on the other end is feeling it far worse than I am.
Having two switches does work well, but I personally feel that an even more useful configuration is the two-stage switch, as seen in the A2 Aviator and LX2 from Surefire. A slight press gives you a low beam, and fully depressing gives full output. (twisting will give constant-on in both levels, like the standard SF momentary switch) Impossible to mess up, unlike the morse code clicking lights that cycle through modes, and no problem to operate with one hand or under stress, which might be a problem with a ‘dial’ type light like the U2.
Personally, I try to keep things simple. No cycle light modes, twist for a certain output, ect…click/momentary on is the way to go.
For outdoors I think that more is better…with a focused beam of at least 120 lumens…that said, I don’t know if I would ever use a light to ID and shoot/no shoot a BG anyway at a range more than about 60+ yds…any further than that, its probly just best to E&E anyway…I’m not military so…
For indoors, it would obviously be more crucial to have light discipline so as not to wash out your night vision or give away your position. Like posted above, you shouldn’t be “searching” with a light anyway. That said, I would still stick with a light about 120 lumens…
I know most here have experience some form of low light training, but if you haven’t, I can tell you from my experience that 120 lumens hitting you in the eyes from close range will literally blind you for about 3 seconds…which is a LONG time…and impare your nv for even longer…using a light properly will increase your chance of survival in a low light incident exponentially.
I did low light training a few days ago. I ran my X300 (tested 210 OTF lumens; https://www.m4carbine.net/showthread.php?t=55402 ) on my carbine. At 50 yards it was difficult at times to determine if the target was a threat or not. At that point I was behind a barricade giving verbal commands. Realistically where I patrol taking a 50 yard shot is risky anyway but if it has to be done, it has to be done. It got easier to see as I closed in but that’s given.
It also depends on the quality of your vision as well. So how much is enough? Even 210 measured lumens is not enough for me at 50 yards.
There’s always going to be variables, smoke, fog, rain, beam focus, LED, etc. that will effect the amount of useable light from any light source. I tend to go with the more is better school of thought in theory but smaller is better in practice.
After using a mini Scout at a course last year I traded my other Scout for a mini and went on. I like lighter weight and for me the mini Scout is a good balance. In a perfect world a 60-65 lumen light will work at 50 yards. When you throw in the variables it might not.
On our SWAT rifles we had and still run a few LED Nitrolons. I’ve been replacing them with the G2X’s as needed. 200 lumens is better than 80 or a 110.
Another issue I’ve seen is the ratings often don’t mean anything. You’ve got to see the light to know how bright it is. Even with our Surefires they changed their ratings and sometimes wonder if they changed anything but the writing on the label. Sure fire was known for under rating and others for over rating.
The bottom line for me is have a light. I prefer mini Scouts on my rifles and X300’s on my pistols but still have a couple of TLR’s and Nitrolons.
what I meant was he dropped a statement without furthering it with a solution. it’s like a teacher I had once who would walk by and look at your work and and say, “no, that’s not right”, and then keep walking - not very helpful if your idea is to help someone understand… if it’s not right, what am I doing wrong, is there anything right about it or do I scrap everything and start over, etc., etc…
you on the other hand have provided examples that give a baseline that can be compared. that does further the discussion.
however, it’s understood that lumens can vary greatly in handheld lights while form factor less so. probably the best advice would be to define the mission first and then taking into consideration the tools appropriate to that, whether flood or spot beam and lumens required to fill that…
For years SureFire has recommended 60-65 lumens as being the lowest output level a person should accept. For me, the lowest I generally want to go is around 80 with a max, if working in an urban environment, of 120-130. I’ve been in a situation or two where the portable sun I was carrying (10X w/ 500+ lumen output) reflected off of a mirror and messed me and my team mates up for a few moments.
The LMS formula is pretty sound if you were to stick with it.
Seb5, I forgot our experience at class last fall. LED and Incan bulbs make a difference when using the light when dust kicks up. Thanks for bringing that back up because there is no free lunch.
I was at a low light class with EAG last November and while shooting into the berm there was a bunch of fine dust in the air. The LED lights, even the most powerful, would illuminate all the dust and made the target difficult to see. Think about driving in fog with your highbeams on, kind of like that. The incan lights seemed to cut through the dust much better. There is a trade off as incans have a fillament that can break where the LED’s don’t. No free lunch.