perspective on lumens

I've begun research on an EDC/hiking style flashlight. I'm trying to get a perspective on what output lumens look like during use.

What kind of sightline distance would these outputs achieve?

10 lumen
70 lumen
160 lumen

My only perspective is a "mini" Maglite AA that's about 10 years old. The current iteration of this product claims a 77 lumen output. Considering the model I have is 10 years old, I don't know how similar/different the two product iterations are, so I'm not sure if it offers a good perspective.

Any general perspectives would be helpful. Thanks.

Lumens do not give distance. The measurement you are looking for is intensity, measured in lux or candela. Why don't lumens give distance? Lumens is some number of photons. Intensity is photons per area.

Imagine a plain 60W light bulb outside in the woods. It might let you see 30 feet on a clear night. It emits about 1600 lumens! Compare that to your 77 lumen Mag Lite, which lets most of us see 100 feet easily. The reflector makes a big difference. To see this directly, compare the mag lite 77 lumens with the reflector on, to the mag lite 77 lumens with the reflector off. This lets you compare a floody light (All lumens, no lux) to a throwy light (All lux, fewer lumens).

You'll not know how you lived with the Mini Maglite - I believe on fresh batteries I've read something like 15 lumens. So pretty much every LED light available right now that I can think of will be not just brighter - but orders of magnitude brighter.

After that it becomes an issue of how the lumens are distributed - big die emitter (i.e. XML) in a small reflector can be quite bright but produce a rather floody beam - XPG in a deep reflector or an optic can throw a long way and appear brighter with less lumens due to the concentrated beam. And as you increase output the perceived differences in brightness diminish - 120 compared to 150 will not appear significantly brighter and 150-300 won't appear 2x brighter (although it will be noticeable).

I've found that highs in the 150-200 range are pretty doggone bright and my couple lights with output beyond that I don't really use the highest outputs that much...

On the maglight website they list the 2AA Xenon (incandescent) at 14 lumens. That is probably what you have.

AnAppleSnail said:

Lumens do not give distance. The measurement you are looking for is intensity, measured in lux or candela.

Click to expand...

Thanks. I just read that in another thread. I'll look out for it.

Gatsby said:

I've found that highs in the 150-200 range are pretty doggone bright and my couple lights with output beyond that I don't really use the highest outputs that much...

Click to expand...

I've read that elsewhere; Around 150 is plenty.

I'm not trying to lite up a field or anything.

Thanks.

Poppy said:

On the maglight website they list the 2AA Xenon (incandescent) at 14 lumens. That is probably what you have.

Click to expand...

Maybe. There was a Minimag LED in September 2006. That is just about ten years ago... FlashlightReviews.com page.

I forgot the LED ones are a good bit longer than incandescent. But if he already has a MagLED (Which he'd have to for 77 lumens) then he already has the length there.

Does your flashlight have a yellow blob or a filament when it's off?

AnAppleSnail said:

Maybe. There was a Minimag LED in September 2006. That is just about ten years ago... FlashlightReviews.com page.

I forgot the LED ones are a good bit longer than incandescent. But if he already has a MagLED (Which he'd have to for 77 lumens) then he already has the length there.

Does your flashlight have a yellow blob or a filament when it's off?

Click to expand...

AnAppleSnail,
Gee... I didn't know I was so far behind the curve, for sooo long I just got some new LED mags last year!

Beefcake,
I'm going with: my thought, that you have an incandescent mini-mag.

Here is a thread that discusses the incan D cell mags a bit.
http://www.candlepowerforums.com/vb...dard-Maglite&p=3684108&viewfull=1#post3684108

In this post it is suggested that a 3D mag is about 45 lumens it also shows how quickly the output drops.

[edit] material deleted... I suggested a particular marketer's video reviews, because he typically compared beam shots to an incandescent maglight. It seems that he changed his review format, and I couldn't locate the videos [end edit]

I have a Zebralight H600w (imho the only headlamp atm ...)
... which has a very good beam, slightly on the floody side, quite suitable for a headlamp

* low ... ~ 3-5 lumen: enough for navigating around in a lodge, to not annoy someone. VERY risky outside
* med .. ~ 60 lumen: good for walking (2nd sub level ~30 lumen: would also work)
* high .. ~ 600 lm: good as additional headlamp for mountainbiking (2nd sub level ~300: the same) ... both way too bright for walking, but when the runtime is enough --> nice to have

(You will annoy everyone else, as Your light is "way too bright" - their lights will be next to useless)


PS: the old MM can be focused and defocused, so the "feeling" that options offer for You, is quite different - but the pure output stays the same ...

Thanks for the replies.

AppleSnail I have a question for you if I may....Re: Candela I am waiting for delivery of a "Intrinsically Safe" Streamlight Poly stinger Haz-Lo (I'd post a link but I'm afraid that would break the rules???) that the specs say is 15000 Candela and 130 Lumens on high. As a guess, what would you think is a safe distance I should be able to see well? 100 feet? 200 feet? Thank you for your (or any others) opinion.

Beefcake the Mighty said:

I've begun research on an EDC/hiking style flashlight. I'm trying to get a perspective on what output lumens look like during use.

What kind of sightline distance would these outputs achieve?

10 lumen
70 lumen
160 lumen

My only perspective is a "mini" Maglite AA that's about 10 years old. The current iteration of this product claims a 77 lumen output. Considering the model I have is 10 years old, I don't know how similar/different the two product iterations are, so I'm not sure if it offers a good perspective.

Any general perspectives would be helpful. Thanks.

Click to expand...

As mentioned, lumens don't correlate to distance, that's measured in terms of lux.

The shape of the beam can make a given lumen output more concentrated, such as most mags do, so you have a teeny spot of light that can be projected pretty far...or, spread out in a wide flood that is right in front of you, or anything in between.


If you look at this thread it might help you to understand:

http://www.candlepowerforums.com/vb...-Easy-to-Understand-Lumens-Vs-Lux-Explanation

SAVAGESAM said:

AppleSnail I have a question for you if I may....Re: Candela I am waiting for delivery of a "Intrinsically Safe" Streamlight Poly stinger Haz-Lo (I'd post a link but I'm afraid that would break the rules???) that the specs say is 15000 Candela and 130 Lumens on high. As a guess, what would you think is a safe distance I should be able to see well? 100 feet? 200 feet? Thank you for your (or any others) opinion.

Click to expand...

With 15000 cd, you should put 1 lux on target at 122 meters, and 4 lux at 30 meters. Depending upon how much detail you need to see will determine how much lux you need on target.

With only 130 lumens, you are going to have a pretty narrow beam of light.
Take a look at that thread linked to by TEEJ

SAVAGESAM said:

AppleSnail I have a question for you if I may....Re: Candela I am waiting for delivery of a "Intrinsically Safe" Streamlight Poly stinger Haz-Lo (I'd post a link but I'm afraid that would break the rules???) that the specs say is 15000 Candela and 130 Lumens on high. As a guess, what would you think is a safe distance I should be able to see well? 100 feet? 200 feet? Thank you for your (or any others) opinion.

Click to expand...

There is certainly a relationship between intensity (Candela, which is lux at 1 meter) and ability to see at a distance. In fact, your ability to see an object at a distance is almost equal to the ratio between the lux on that object, and the lux of other objects. Now, 100 lux is about like a dim room. If you look in through a sunlit window, you can't see 100 lux (Because sunlight lights the wall at about 10000 lux). But at night, you can easily see (Room at 100 lux, wall at 1 lux).

The ANSI flashlight spec defines 'beam distance' as "Where a target is illuminated to 0.25 lux," about like decent moonlight. In a dark field, you'll see a white T-shirt at this distance. But in the woods, you probably won't see so far. In the city (with other lights competing) you certainly want.

ANSI beam distance = square root of (Candela x 4), for 1/4 lux.
sqrt(15000*4) = 244m ANSI beam distance

I don't believe 0.25 lux is 'seeing,' so I cut that in half once or twice, depending on the environment. This gives you an ability to compare - Your light has about two thirds the reach of an LED Mag 2D. However, I wouldn't expect to see much at 240 meters, either.

I say that you'll see reasonably well in the dark, out to about as far as a football field, if it's clear out, and you aren't trying to spot hidden things.

Lumens get split into two parts of the beam: Spot and spill. The spot is the bright blob of light. The spill is light that does not touch the reflector, but goes straight from the LED. It is much dimmer than the spot. A big, deep reflector puts more lumens in the spot (Allows a stronger or bigger spot) and fewer lumens in the spill.

This is good stuff. Thank you all.

Beefcake the Mighty said:

I've begun research on an EDC/hiking style flashlight. I'm trying to get a perspective on what output lumens look like during use.

Click to expand...

I want to address another aspect of your question. I found and continue to find the table in post #1 of the link below immensely useful in understanding at what number of lumens there will be an appreciable perceptible difference from some other number of lumens.

"Perceived Brightness Index"
http://www.candlepowerforums.com/vb/showthread.php?271967-Perceived-Brightness-Index