Flashlight Lumen question

What would you guys consider to be the minimum number of lumens for a flashlight to be bright enough to allow you to navigate safely? 10 Lumens? Thanks

Depends on the situation: the terrain and natural light (moonlight). I would say atleast 20 - 30 lumens, unless the only thing you do is answering natures call.

To little light and you will see things to late, especially when walking fast. I have almost run in to tree's because mine headlight was too dim (almost dead batteries). Not funny when you miss something worse...

I don't know what type of terrain you are trying to go over, but I have used the Mini Mag for years it has 15.5 lumen, Lately I have switched to the 3 watt led and I have no idea what the lumens on it are , but it works great and you have your choice of power plus strobe mode. Works for me.

No idea, sorry. I would like to point out that red LEDs, while significantly less bright by default, allow for uninterrupted night vision.

Wow, this question is hard to answer.

Depends on the shape (width) of the projected cone, the brightness and size of the hotspot (center), etc. Luminosity measures how much overall light is provided but tells you nothing about how focused the light is or how useful it will be.

Also depends on how far ahead you want to see, whether you want to preserve night vision, do you care about illuminating the periphery? (Are you near cliffs? Crevasses? Are you caving?) For example, if you're biking, you want to see much further ahead than if you're walking.

A 200 lumen unfocused beam can be useless outdoors. And the glare can be so bad so you can't see more than a few feet ahead of you. A 40 lumen beam can throw a sufficiently bright hotspot that you get by just fine. It all depends on the light.

And remember, brightness is logarithmic. To double the brightness, you need an exponential increase in power. So, all things being equal, the difference between 1 and 100 lumens appears enormous. The difference between 100 and 1000 lumens is much less dramatic. (It's the same with sound.)

Lumens are also incredibly tricky to measure. Most manufacturers don't provide incredibly accurate ratings, as you need to enclose the flashlight in a sphere and measure its total output. And if the flashlight is unregulated, the brightness will start dropping off almost instantly as the battery voltage starts to drop.

You might want to scan through http://candlepowerforums.com for some introductory material on flashlights.

That is for 1 Watt Luxeons. CREE LEDs can get 131 lumens per watt.

And the numbers are just estimates. Actual output depends on the reflector, lens cover material, regulation, whether it's over-driven, the heat sink for the head, etc., etc.

How much would 4.8 Watt be?

Hmnn, in this case, I have no idea.

But it would probably be best deemed a paperweight. It looks like an ancient 1st generation LED light that Victorinix slapped their branding on and I doubt it comes close to 20 lumens.

Time to get a new light?

I went camping a few weekends ago and took a Fenix L2D CE. On the lowest setting (9 lumens) I was able to maneuver at night quite well. I had the flashlight attached to a Nite Ize Headband.

Hard to standardize when no one wants to have four of the same headlamps or flashlights. But I am trying to work towards mostly AA's as well.

I wish two other areas would be standardized and we have a better chance of it happening here than in batteries- memory cards and light output. I have three memory cards, all do the same thing, none of them compatible with other devices. As to watts, lumens, etc. Just pick one and stick with it is my advice to those companies. Stop toying with the consumer.

Back to the main question. Depending on where ur at, use a small chem light to mark ur tree or trench. Won't help missing a branch or root but the light you use wont need to as bright either.

i always recommend items that have multiple uses. In this case alight with multiple brightness levels.

Yeah, sometimes with a full moon, I don't even bother with a light. And conversely, if it's really dark, a light bit of light will get you a long way. It totally depends on ambient brightness and environment.

Most flashlights will work fine for most people in lots of situations. After all it’s just a flashlight, don’t make it more complicated then it is.

Ha! I dare you to post that on http://candlepowerforums.com.

If walking in the woods and you have a chemical light, tie or tape it to the end of a stick or walking pole and hold the stick with the light in front of you down by and in front of your feet. This way you can walk and see where you are stepping.

I don’t care what a bunch of flashlight Geeks think…

Flashlights should provide a few things.

They should be durable enough to work in the situation you use them in.

They should use an easily found power source.

They should last more then a short time on a set of batteries (many of what are called “tactical lights” fail this one, and fail miserably!) They run off the CR123 batteries (more expensive) and only run for 1 ½ hrs, this is a very poor choice of a light for a survival situation.

And they should provide enough light to see what you are doing.

All the flashlights I have provide enough light, some of them will light up the whole yard (60 feet wide and 200 feet back from the window) and the front of my garage (130-feet away from my window) like it’s daylight. While this is real manly and cool, it’s hardly needed in most situations. In fact it’s needed in very few, we just tell ourselves we need it.

I have to take issue with this. Flashlights are as variable as knives or any other piece of equipment.

If you're happy with a 2xAA Maglite as your survival light in the woods, more power to you :), but I'll take a regulated, variable output light that steps from 10-200 lumens, preferably with a strobe, 3 to 50 hours run time, with an aluminum reflector and UCL lens any time. I'm also very particular about the balance of throw to spill and the size and color of the hotspot in my lights. (Most white LEDs are anything but white.)

And it makes all the difference in the world if you're using it indoors, outdoors, in pure darkness, in mild illumination, in fog, under/near water, near hazardous fumes, etc.

If you think all flashlights are the same, you may not know enough about flashlights...

Fitz -- a flashlight geek

Never said they are not important (heck I carry one in the daytime)

Never said I use Mag lights (at least not for several years, mag lights are well behind the times in regard to the bulb)

I have fully embraced LED flashlights because of their greatly reduced power consumption.


I don’t need (as I would guess most people don’t) a variable power flashlight.


I'm also very particular about the balance of throw to spill and the size and color of the hotspot in my lights. (Most white LEDs are anything but white.)

So it’s color is different then an incandescent light bulb, how does this stop it from lighting up my yard or a room? It doesn’t!

If you think all flashlights are the same, you may not know enough about flashlights...

Never said that, I said most flashlights will work in most situations.

Try this for 2-weeks, go to a store and buy a normal LED flashlight with o-rings.
It will work if you are indoors, outdoors, when it’s dark, fishing (close to water), when it’s fogy out, and a whole lot of other places you can imagine.


Give it a try, and if you are honest with yourself, you will admit that it did the job just like the super light you have.

I bought one at Target for $19.00, it’s waterproof, explosion proof and I use it for probably an hour every 2-days. Its 2-months old still running on the original batteries and still bright enough to light up my garage from the house (130 feet away.) I use it for a headlight on my bike when riding it at night so it gets at least ½ hr of use a night.

You don't need an expensive sebenza to get a good folder. But some people who are into knives still wan't one. They know that 10 times the price isn't goeing to provide a knife witch is 10 times better.
The difference is in the details.

The same goes for flashlights. Fitzoid is very critical about flashlights, and so it seems he is also a flashaholic. Besides, fully regulated and variable output is definatly a nice feature to have. Not every situation calls for the maximum brightness.

What light are you talking about here? I am not up to date on a lot of lights and I am not sharpshooting here, but my SureFire with 120 watt bulb runs 20 minutes. What light runs 200 lumens for 3 hours? If what your describing fits the $$$, I'd probably get it.

In my current EDC I carry an old red maglite with a Nitize LED kit (great light BTW). I also carry a e+lite headlamp. I have another dozen or two headlamps, electric torches and lanterns around the house. The Surefire is just for show.

Well the thing is, regulated multi stage flashlights can be a pain to operate. Especially those with more than just a few modes. I really don't want to choose from 20 diffrent light outputs and i really hate to programme mine lights, with just one button.

But some manufacutures has multistage levels, without too many features like the Fenix range of flashlights. There P3D and L2D versions can put a huge amount of light with good battery life.

Nah, I'm good. This one is plenty bright for my needs. Disappointing, sure, but once you start upgrading to the latest model, there's no going back.

Guess I was exaggerating slightly...

Check out the Fenix L2D Premium. It provides regulated 180 lumens for 2.4 hours on 2AAs. But it does give 12 lumens for 55 hours!

But the days of unregulated, 20 minute runtimes are over for me! Surefire, RIP!

+1 on Fenix. I've retired my Surefire to backup status. I bought the premium Fenix 1xAAA, the 1xAA and the 2xAA body which uses the same head. Around $100, IRRC, for a very versatile and reliable set of lights that meet all of my on-duty and off-duty needs very well.

Jeff

Sounds like a great light (and this isn't the first time I hear about it, either), but it's just a wee bit too pricey for my undergraduate budget. Besides, like I said: there's no going back...

Thanks. I have not seen a Fenix before. I will give them a look. I tend to go moderate to cheap on my preparedness stuff because I use it hard testing it out. I buy bic's over torches. I have a zippo from 20 years ago.

I recycled a maglite with a Nitize LED. Thank God LED's last so long.

I remember my starving undergraduate days. I was working full time, going to school full time, and pinching every penny to pay my and my wife's tuition. Still, I remember those as happy days . . .

Fenix does have a nice single level output 2xAA model on sale for around 35 bucks, if that helps, at Lighthound.com

Jeff

Ah, I have done this.

I have taken at least 10 different flashlights on many occasions to test them out, not withstanding the fact that doing so makes the wife question my sanity. Without question, they perform differently.

It's just like your car's highbeams are useless in fog, that's exactly how a white LED performs. This is why I still carry a yellowish Xenon light with me. I have some red LED lights which preserve night vision and are perfect for looking at star charts (the Proton is my favorite). And I have lights with a lot of throw and other lights with a lot of spill that illuminate fields but aren't very useful for navigating. Some are too heavy to be practical and are some are too light to have any real battery capacity. I like wide lights with spill for dog walking (which I do for half an hour every night), so I can find her if she runs off to sniff something without my yelling for her. Highly focused beams aren't very helpful for that.

So, I always test my flashlights, as I do all my gear. I can't say I'm a huge fan of the "bang the light on concrete" test that so many people seem to love, but I do like knowing how well everything works.

1 lumen is enough to light up my bedroom, for me to walk from my bed to bathroom without stepping on my son's lego blocks.

However, if you are walking in the forest trails or even cycling. Then I would say if more light is needed the faster you travel. For cycling, you may need 120 lumens, enough light to cover 30~50 metres of the ground in front the bike.

Tactical lights are designed to give maximum brightness for a short duration maybe 20minutes. Their intended users are law enforcements, etc.

Survival lights are designed to give a long duration of light (not maximum brightness)

Hi Firefly,



It can also be extremely useful to allow the flashlight to give the maximum brightness in certain conditions. For example if you are stranded in the wilderness at dusk/nightime and you can hear the sound of a search aircraft in the distance, then an SSC P7 type flashlight flashing an SOS at over 600 Lumen for 2-3 hours would be preferred over a Maglite AAA Solitaire.

Agreed, maximum brightness may be useful in certain conditions.


if a search aircraft is actively looking for you and you can hear it, it is unlikely you have flash for 2~3 hours

A multi mode flashlight may not flash the SOS signal at maximum brightness.

The recent flooding in NO, there was 1 guy who had several bright tactical flashlights and 40~50 CR123A. His experience was that high power flashlight was too bright for indoor use and it takes only a few days before his stock of CR123A was used up. His low brightness light was more useable and it serve him throughout the floods.

In answer to the original question, 10 lumens is more than enough to navigate by at pedestrian speeds. I've gone through lava tubes with less, and done just fine. If you have to run for your life, maybe not so much. When I had to run, and I wasn't concerned with becoming a beacon for a set of crosshairs, 50 or 60 lumens was pretty much necessary.

In other words, to find the privvy at elk camp at midnight, a small led light such as what DR puts in his pocket survival kit is acceptable. For making a bunker run during a mortar attack at 2:00 am when the generator has quit (again), a G5 Nitrolon was highly desirable.

I wish I'd gone the extra $12.00 and gotten the Fenix L2D Premium, but I'm happy with the Fenix L2D CE. I probably would have bought the Premium had I noticed it. The Fenix Store Site is a little whack to navigate.

The Fenix has taken the place of my Pelican M6 2330, which is now relegated to a backup light for similar reasons as your Surefire.

Agreed. It's also about enough for me to read by. Generally, the darker it is, the less light you need, because your eyes adapt.

I am a bit surprised by this. It's good to have 1 lumen or 10 lumens available when that is enough light, in order to avoid disturbing other people, ruining your night vision more than you need, and to get extended battery life. It's also good to have 120 lumen available for when 10 isn't enough - which it sometimes isn't. A general-purpose survival light should have at least 3 levels, in my opinion.

As for UI, that's one of the things which distinguishes a well-designed light from the others. I have an old Surefire U2, where you just twist the bracelet to one of 6 positions. The Photo Freedom is pretty good, too: press and hold to start dim and ramp up to bright continuously, release at the level you want; click to get bright, then press and hold to dim down and again release when it's at the level you want.