Is a Lumen a Lumen everywhere?

Murphy625

Newly Enlightened
Joined
Jan 24, 2014
Messages
31
So as some know, I've been looking to purchase some flashlights to put in my Faraday cage. Got some good suggestions, decided to waste a couple bucks and try one of the cheap things on Ebay..

So I bought one of these:
http://www.ebay.com/itm/Castnoo-SK6...142396?hash=item21232e113c:g:4r0AAOSwdGFYoriJ

Notice its listed as 3500 LM..
I own an old Maglite that I converted to LED using a Terralux bulb that is listed as 200 Lumens.. My 200 Lumens Maglite is easily several times brighter than the ebay flashlight that is listed as 3500 Lumens.

What's going on? I can understand the sellers exaggerating the brightness a bit but this isn't even close..
 

Murphy625

Newly Enlightened
Joined
Jan 24, 2014
Messages
31
So I have a bunch of small flashlights now that all run on either a single AA or three of the AAA batteries.. They last a long time but are limited to around 100 lumens or less.. Nice for in house work, not so useful outside.

My Maglite terralux conversion works nice! It says its rated for 200 lumens and its pretty good.. but....

What would you guys recommend for something in the 500+ lumen range? I mean, something that ACTUALLY puts out what its specs say it puts out? I'm not going to be going scuba diving with it and I don't plan on dropping it out of an airplane.. but maybe something on the quasi-quality of a maglite?

Suggestions?
 

lightfooted

Enlightened
Joined
May 6, 2010
Messages
989
So I have a bunch of small flashlights now that all run on either a single AA or three of the AAA batteries.. They last a long time but are limited to around 100 lumens or less.. Nice for in house work, not so useful outside.

My Maglite terralux conversion works nice! It says its rated for 200 lumens and its pretty good.. but....

What would you guys recommend for something in the 500+ lumen range? I mean, something that ACTUALLY puts out what its specs say it puts out? I'm not going to be going scuba diving with it and I don't plan on dropping it out of an airplane.. but maybe something on the quasi-quality of a maglite?

Suggestions?

Olight M21X2 ...you can still find them relatively cheap and yet they throw over 700 lumens out in a nice narrow beam. Meant as more of a small thrower for Law Enforcement/ S&R it operates on a single 18650 or pair of 123As. I use mine at work for reaching into very dark corners at a distance. I would rate their quality high enough to compete with Surefire myself...I know many folks would disagree here but I own both and feel it is justified. Olight also makes an M22 and an M23 which are improvements to the original M21 Warrior line.

They are also supposed to be releasing a new Warrior line sometime this year that will likely exceed 1000 lumens...can't wait to see em. Understand that there are a LOT of options out there now...too many for me to think of all by myself so I just chose the most recent purchase I made that made me very happy.
 

Chicken Drumstick

Flashlight Enthusiast
Joined
Dec 9, 2011
Messages
1,478
Location
UK
So I have a bunch of small flashlights now that all run on either a single AA or three of the AAA batteries.. They last a long time but are limited to around 100 lumens or less.. Nice for in house work, not so useful outside.

My Maglite terralux conversion works nice! It says its rated for 200 lumens and its pretty good.. but....

What would you guys recommend for something in the 500+ lumen range? I mean, something that ACTUALLY puts out what its specs say it puts out? I'm not going to be going scuba diving with it and I don't plan on dropping it out of an airplane.. but maybe something on the quasi-quality of a maglite?

Suggestions?

Your best bet is to become and 'informed' purchaser, i.e. have an actual understanding of what you are buying, how it works and why it will do what you want.

As per your opening post, an informed purchasers would know a claim of 3500 lumens from such a light is just comical. A bit like seeing a commuter car claiming 12,000bhp and 545mpg. You'd know straight away it was bogus.

Small lights with low power sources and often large LEDs will tend not to make great out doors lights. The beam profile will be wrong, this is why a 180-200 lumen Maglite drop in can easily out throw a 900 lumen tube light.

Read up and understand these differences and it'll help you make a very informed purchase :)
 

bykfixer

Flashaholic
CPF Supporter
Joined
Aug 9, 2015
Messages
15,281
Location
My own little Idaho
Maybe they shoulda placed a decimal in that number...
35.00? That's crazy. Perhaps it shoulda been 3500 candle power?

Yes a lumen is a lumen everywhere. Trouble is so is false advertizing.

In the meantime stick with Maglites until you learn about the other stuff available.
 

iamlucky13

Flashlight Enthusiast
Joined
Oct 11, 2016
Messages
1,140
A lumen is officially defined in terms of the International System of Units.

Therefore, a lumen is a lumen everywhere.

It is also true that a liar is a liar everywhere.

There are a ton of variations on the sub $10 zoomies, and almost all of the manufacturers of them lie to varying degrees. The best flashlight makers in the world can't get 3500 lumens from a light powered by a 14500 battery.

Speaking of which, assuming that light even runs at all on a AA battery and that's what you're using, it will likely be significantly brighter with a 14500 lithium ion battery. However, lithium ions, or at least lithium ions alone, are arguably not the best choice for an emergency kit.

If you're looking for a budget AA-powered light, the Jetbeam Jet-1 MK is frequently put on sale by some Chinese discount retailers for a really good price. You just have a wait a long time for shipping, with no tracking info:
http://www.gearbest.com/led-flashlights/pp_368125.html
 

iamlucky13

Flashlight Enthusiast
Joined
Oct 11, 2016
Messages
1,140
By the way, here's probably the worst flashlight scammer I've seen so far, spotted on my local Craigslist (let me know if the screenshot doesn't show up).

Even the manufacturer of the LED they claim to be using says you can't get much more than 1000 lumens from an XM-L2, and you can buy that entire kit for $10:

www.ebay.com/itm/Focus-Zoomable-CREE-XML-T6-LED-Tactical-Flashlight-W-18650-Battery-Charger-Case/351810703642

LU5DxU4nU7_wEF0cudW8Dt0Z9M8-OLyPS8LbjQ7VJ7QkcIeSy3QF38rTzj3APveXxaUq12Mt64j3Q1KpDif5YvI3sefPyz4ckTVnZXulgqr-vh_TbiVadR7lyNC-4ZkDpn0EeX6nwkFK0A1UGmpzBeCiDJikHKFDKKgeGteA18dKIj1Z97NnoKcJXnT7SwVtRGrVaxksAWyM3PMxX2fr7cvsQpj7egNO1lMuooLoWev30ployfnqPNF3lT2O6vg8uDTh2SXQOQxKT7dP7azDAB9vkXLTXZFarA8wC_YxSEr8yuzAZQZZ1qG6yRWKbsRhk54_8c5Ltg7CyY-N1tiipO14OI3SIKvf6BMzzp0DdFOeH2HtWI0DlVsAM6apShJWiSxkRphjZjIcXGWgOR2hqEL1T3vnU5H7iAC6_ntahdin1yIvqU-urr1iq3B7abk_lECBtoFxSBOCLzglCD2u-bbMvmu6L6kb36DWWwczbEOv14ye1YPYBy_xvBgpI39RDHHyCq7Anadt8Vzq-rvvBwy2z2z7_mpIn_FDdxR7o7M_5MK7Y27llnmi1ZSwY_ppAilZsIwPwGFMUEfxtVX-xRqM_sZksdCEtiHQjrAq86n4PUHUZLMPLgBYNYLKrAaZh5P7ISREshdn3lSbafdFYXnaJxkZCTqTTvW33mdEfA=w519-h609-no
 

alpg88

Flashlight Enthusiast
Joined
Apr 19, 2005
Messages
3,864
those are great loaner lights, i once bought half a dozen. have only 2 left lol, they saved me few good lights.
bykfixer got it right, they are about 35lm. of nasty blue light
 

mfunnell

Newly Enlightened
Joined
Jan 12, 2017
Messages
22
Location
Sydney, Australia
Is a Lumen a Lumen everywhere?
Well, yes. But you have to understand: there are mainstream lumens and various types of alternative lumens.

The mainstream kind are the only type "they" want you to know about. "They" try to bamboozle you with all kinds of guff about physics, and measurements and instruments and engineering - to convince you that mainstream lumens are the only real kind.

But then there are the alternative lumens, that those elites don't want you to know about. While there are various kinds of alternative lumens, the main ones I'm aware of are:

Late Night TV Lumens.These come in lights with lumens that are not available in stores, and can be purchased in only 4 installments of $18.95. But wait - there's more! If you call within the next 30 minutes you'll also recieve not one, not two, but three(!) sets of Ultra-Leak-Alka-Lumen batteries. Don't wait! This offer can't last!! [*void where prohibited]

Auction Site Lumens.These are better, with lumens that are more alternative than even Late Night TV Lumens (and there are more of them). They must have more better lumens, because such lights usually have 'Fire' (or 'Eye') in their names. And nothing says more lumens better than 'Fire!' (or 'Eye!'). All this in lights which are precision-engineered and manufactured in Germany, Japan or the USA but for some reason must be shipped from Shenzhen. Which will take 6 weeks (if ever). But they're cheap! And they're even cheaper if you send money via Western Union, bank transfer or cash-in-an-envelope to bypass those nasty payment fees[*].
[*and any prospect of seeing a decent product, or any product - or your money, ever again]

Spam Lumens.These are the most alternative alternative lumens of all. These lights are so super-secret that they are only known to US (or perhaps Israeli) Special Forces, the purveyors of this Newly Released Secret Product, and you - the one special individual in all the world they've decided to share the secret with. Only very special people are chosen for release of such Ultra-Secret devices so you'll have to pay a premium price. But it's worth it to know you're the only person in the world this offer is being made to.

I say phwaaah! to the maistream elites. Choose your preferred type of alternative lumens[*] and go for them.
[* special super-secret spam lumens not available to all customers]

...Mike
 
Last edited:

Woods Walker

The Wood is cut, The Bacon is cooked, Now it’s tim
Joined
Jun 8, 2008
Messages
5,434
Location
New England woods.
Sure... 3500 lumens from 1XAA running a Q5 (therefore XR-E). All for 3 bucks shipped from California. What's not to believe?
 

Woods Walker

The Wood is cut, The Bacon is cooked, Now it’s tim
Joined
Jun 8, 2008
Messages
5,434
Location
New England woods.
My zoomable 1XAA power light not only glows blue with an agreeable space alien abduction angry blue tint but is an actual 35 lumens from an unknown LED all behind a crazy walleye..... eye lens.

 

bykfixer

Flashaholic
CPF Supporter
Joined
Aug 9, 2015
Messages
15,281
Location
My own little Idaho
Ok now I gotta spend an hour cleaning the coffee spray off my keyboard after reading mfurnells hilarious post.

Note to self: make sure not to take sip of coffee while reading posts by that guy...
 

idleprocess

Flashaholic
Joined
Feb 29, 2004
Messages
6,187
Location
dfw.tx.us
When evaluating lumen claims, you need to understand the technology to determine the credibility.

Battery Capability : The number of watts that a cell can deliver is the ultimate limit of how much light a flashlight can put out. Alkaline AA cells are going to struggle to deliver 2A; assuming they also manage to deliver that at their nominal 1.5V that's 3 entire watts. Conversely, a quality high-power li-ion cell might deliver 25A at 3.6V or be capable of 90W.

Source Efficiency : Incandescent filaments might hit 30 lumens per watt. Arc lamps are often in the neighborhood 40-90 lumens per watt. LED is perhaps 150 lumens per watt. A perfectly-efficient source might hit 300 lumens per watt.

So, in a simple perfect-world example, your 1xAA light powered by an alkaline cell might be capable of 450 lumens of output.
But life is more complicated than our example.

Driver Efficiency : Nearly all LED flashlights regulate current to the emitter somehow. Most lights need to address the mismatch between supply voltage (bateries) and the LED voltage (typically 3V for white LEDs). This can be a simple resistor, a voltage boost circuit (such as your 1xAA light requires), a buck circuit (to drop the voltage from multiple batteries), a PWM circuit (which rapidly pulses the LED to regulate brightness), and potentially a microprocessor to manage multiple modes. All of these consume power on their own, reducing the power delivered to the LED itself.

Optical loss : All optics have less than perfect efficiency. Reflectors, TIR optics, flashlight lenses - they all trap a percentage of the light produced. A really good system has perhaps 85% efficiency; an average system is closer to 70% efficient.

Heat loss : Electrical components in the system lose efficiency with heat. LED output drops at normal operating temperatures. Drivers often lose efficiency with heat - particularly those with active components like boost and buck. Batteries' internal resistances often increase with heat, resulting in lower net power delivery to the driver and ultimately the LED.

So the real-world limit for 1xAA alkaline seems to be around 150 lumens. 1xAA NiMH can offer better performance, but flashlight manufacturers don't seem to design for that since it could make alkaline performance spotty. 1x14500 Li-Ion cell (same dimensions as AA) can easily double the performance of alkaline AA and more, but that's likely going beyond the thermal design that manufacturers throw at the 1xAA formfactor.

Lastly, you will have to realize that you've ventured into the minefield of eBay marketing claims. Merely dishonest brands will specify the theoretical best performance of the LED and put that in their spec sheet (because taking actual measurements is hard); the true hucksters will outright lie as you have experienced firsthand.
 

Woods Walker

The Wood is cut, The Bacon is cooked, Now it’s tim
Joined
Jun 8, 2008
Messages
5,434
Location
New England woods.
Well, yes. But you have to understand: there are mainstream lumens and various types of alternative lumens.

You missed one.

Scam crowd funding lumens. Some promise 8,000 lumen LED flashlights which are able to ignore basic laws of physics. Then there is heat defying HID belt worn lumens which also hits that magic 8000 number. Brighter than a car's headlamps but cool to the touch. The heat just vanishes much like the 8,000 lumen LED light. Others promise lumens from the differential between your finger heat and the room temperature. Just send your money to Russia (in all three cases) then wait......and wait.......keep waiting........
 
Last edited:
Top