Misleading specification or Caveat emptor?

[HKJ]

When looking at ad's for flashlights, some of the specification are not always what they appears to be (or maybe exactly what they say). Some manufactures are very good at specifying their flashlights, other forget to mention some conditions (or hides them in small print), making the paper specifications look better than the flashlight is in real life usage.

Some examples I have see are these:

Maglite: 3 watt led: Yes they are using a 3 watt led (I suppose), but they are not running it at 3 watt.

200 lumens: Is the value out the front of the flashligt or is it from the bulb/led? (i.e. torch/bulb lumens)

200 lumens, 30 hours: But not at the same time!

xx watt: Specifying how many watt is put into the led, does not say how much light gets out and sometimes the specification does not event say what is put into the led, but is only used to position the flashlight output relative to the previous model.

xxxxxxxx candlepower: Scaling the output back to the reflector is not correct, the scaling only works for a point source.

runtime xx hours: What is the stopping conditions for runtime: 50%, 1 lumen or ? For some light the difference in runtime can be very huge between a 50% or a 1 lumen condition.

xx lumen: When is the lumen output measured: With fresh batteries or with nearly extinct batteries or somewhere in between? This is very important with incandescent flashlights and unregulated led flashlights, and less with well regulated led flashlights.


Most of these specifications are correct, but can be misleading when not stating the conditions!

Any other "misleading" specifications or comments to this?

 

[kramer5150]

I disregard performance-spec sheets. They are mostly fictional marketing hype to lure customers. Ebay sellers are the worst. Although some of the popular CPF brands are more honest than others.

Some of those "25x brighter!!!" specs are pretty pointless.

One thing I don't understand is why they blatantly advertise Luxeon all over the product packaging... yet the newer Cree based lights mention nothing of their (IMHO-superior) emitter brand? To the average joe-consumer at Target or wally-world, the marketed Luxeon hype would appear superior to the more subdued Cree based products.

????

 

[HKJ]

I disregard performance-spec sheets. They are mostly fictional marketing hype to lure customers.

I would not agree with that, I believe most specs are honest, BUT your have to know the conditions and read them very careful.

But your are probably correct about some ebay sellers.

 

[precisionworks]

I don't understand is why they blatantly advertise Luxeon all over the product packaging.

Luxeon sounds like Luxury

Luxury sounds like Lexus

Lexus equates with quality

And they all have 1 million CP

 

[LEDninja]

Maglite: 3 watt led: Yes they are using a 3 watt led (I suppose), but they are not running it at 3 watt.
3 watt LED refers to the LuxIII as opposed to the Lux1. Mag is actually better than most in actually driving it above 2 watts (at least until the temperature protection kicks in). Also see below.

xx watt: Specifying how many watt is put into the led, does not say how much light gets out and sometimes the specification does not event say what is put into the led, but is only used to position the flashlight output relative to the previous model.
xx watt - there are 3 ways the xx watt is used.
1) Initially it is just the watt rating of the LED. Lux1=1 watt, LuxIII=3 watt.
2) The power drawn from the battery.
3) The imagination of the marketing department.
There is actually a method to the madness:
'1 watt' uses a 1 watt LED. 350mA. 24-25 lumens out front.
'3 watt' uses a 3 watt LED in a 1 watt light. 350 mA. 28 lumens. (Except Surefire who built a true 3 watt light 75 lumens).
'5 watt' is a 3 watt LED in a 3 watt light. 700 mA. 75 lumens. '3 watt' was already used (see above) for an inferior light. Anyway 3 watt across the LED + 2 watt across the dropping resistor = 5 watts.
'7 watt' is a 3 watt LED overdriven at 4 watt by 2xCR123A (6V). The other 3 watts is wasted as heat across the dropping resistor. 1000 mA.
'6 watt' is used by some manufacturers for a 3AAA version of the '7 watt' when it was pointed out 3AAA (4.5V) cannot produce 7 watts.
'10 watt' is a K2 LED which can be overdriven above 1000 mA.
I lost interest in tracking at this point but have seen claims up to '18 watt'
Some manufacturers just claim the max LED rating (see '3 watt') so the Terralux K2 drop in for the minimag has a '5 watt' rating even though the lack of heat sinking forced Terralux to run it at 1 watt.


200 lumens: Is the value out the front of the flashligt or is it from the bulb/led? (i.e. torch/bulb lumens)
xx lumen: When is the lumen output measured: With fresh batteries or with nearly extinct batteries or somewhere in between? This is very important with incandescent flashlights and unregulated led flashlights, and less with well regulated led flashlights.
xx lumen is always measured with fresh batteries as that gives the biggest most impressive #.
Depending on manufacturer this is rated 3 ways.
1) Arc and Surefire send their torches to a lab and you get torch lumens.
2) Calculate lumens based on power to LED and LED chart to get LED lumens.
3) Put the highest # they can find from the LED manufacturer. I can spot these fairly easily. 42 lumens for a Lux1 (~25 torch lumens). 125 lumens for a LuxIII (28-75 actual lumens depending on driver). 900 lumens for the SSC P7 (the currently shipping C bin is 700-800 LED lumens, allow 65-80% transmission through the optical system and I get 455-640 torch lumens. Of course the marketing saw the 800-900 lumens unotainium D bin spec and put it on the torch.

200 lumens, 30 hours: But not at the same time!
Aircraft manufacturers do the same thing. 30 tons for 500 miles or 5 tons for 3000 miles.

runtime xx hours: What is the stopping conditions for runtime: 50%, 1 lumen or ? For some light the difference in runtime can be very huge between a 50% or a 1 lumen condition.
Battery often not specified. Interesting for a Fenix L0D NiMH runtime is 3X alkaline while the Fenix E0 or E01 alkaline runtime is 2X NiMH.

Some of those "25x brighter!!!" specs are pretty pointless.
At least you know it is not a 5mm LED light. Probably a Luxeon 1 (did I mention 24-25 lumens).
2x usually mean a Nichia CS (5.5 lumens) instead of the Nichia BS (3 lumens).


One thing I don't understand is why they blatantly advertise Luxeon all over the product packaging... yet the newer Cree based lights mention nothing of their (IMHO-superior) emitter brand? To the average joe-consumer at Target or wally-world, the marketed Luxeon hype would appear superior to the more subdued Cree based products.
The early 5mm LEDs are dim. Then Lumileds made the 1st useful LED the Luxeon. The Chinese quickly made clones but they are crappy so users insisted on the genuine Luxeon. So Luxeon and Made in USA was used to identify the real thing. Outside CPF and its sister forums in other languages Cree, SSC, Rebels are not well known so the less expensive Luxeon (the R&D and assembly line costs are already paid for) is is still used for the uninitiated.

 

[Empath]

Inquiries and discussion of manufacturer and dealer marketing methods and activities should be done in the MarketPlace. If dealer/manufacturer specific, the Dealers' Corner or Manufacturers' forum would be a good place to raise the questions. Not being specific for anyone though, I'd recommend addressing the topic in one of the off-topic section forums.

It being a marketing discussion, we'll close it here.

Edit to add: On reconsidering, flashlights are sufficiently mentioned, permitting the continued discussion here. The thread is re-opened.

I apologize for interrupting the flow of the discussion.

 

[Empath]

Bumped, to permit a reintroduction of an administrative stalled thread.

 

[SilverFox]

Hello HJK,

I think that part of the problem is that flashlight manufacturers don't have an actual standard that they can work from.

I am not saying that a standard would change the various advertising claims, but it would at least give some target to shoot at. Take a look at the battery manufacturers. There is a standard to determine capacity and cycle life, but we all are aware that some of the labels don't match what the actual capacity of the cell is.

I was quite surprised to find that when we had our light meter benchmarking lights certified, there was no "standard" practice to measure them. I had to approve of the tests that the lighting laboratory proposed. I told them what information I was after, and they provided the procedure they planned on using to obtain these results.

Of course, I found this a little unusual, so I began asking more questions.

It seems that there are some general guidelines for measuring the light from flashlights, but the specifics are open to "interpretation." To me, this information suggests that while a flashlight manufacturer may list the lumen or candlepower of their lights, a competing manufacturer, using the same measuring equipment but not necessarily the same procedure, may come up with something a little different.

When I asked why there wasn't a set standard, I was informed that no one was willing to sponsor the forming of a standard.

When I read that XXX flashlight is supposed to be putting out XXX lumens, I also wonder how they came up with their figures. I pushed a little further and found out that it is possible to "adjust" the geometry of the light measurement to vary the results.

I don't fully understand everything involved with taking a light measurement, but I believe it is a little more involved than checking the voltage of a battery. With no standard, and the possibility of varying results, I am surprised that the flashlight manufacturers list their numbers at all. I guess there is some benifit to the marketing people, the argument that our light is brighter than yours does seem to sell more lights, but I think this whole thing is a mess.

Fortunately, people have made their own integration spheres, or boxes, and share their results. Unfortunately, their numbers are only as good as their procedures and the light meters they use to take their measurements.

One of the "secrets" that came out of my discussions was an unusual request from several spotlight manufacturers asking that the light measurements be taken at a specific distance. The lighting lab people were also curious about this, and they discovered that there was a crossover point in the beam, before it was fully developed, that actually registered a higher candlepower at that distance than it did at any other distance.

In this case, a manufacturer could examine the characteristics of the beam, pick the crossover point, send the light to a lab to have "official" measurements done, specify the distance, because there are no standards that would indicate a different distance, and come up with their 2 million candlepower rating, and say it is "verified" by lab testing.

I am not sure where that leaves us, but maybe we should back up a little. There are standards for measuring lamps. Maybe we should encourage manufacturers to specify lamp lumens, with the understanding that a reflector will change the shape of the beam, and a "window" will most likely cut down on some of the light getting out of the flashlight that the lamp is installed in.

Perhaps the manufacturers could spend some time educating the general public on why their approach is better, and give us something a little more meaningful than simple "output" claims.

Tom

 

[NA8]

Nice post, SilverFox.

 

[HKJ]

I think that part of the problem is that flashlight manufacturers don't have an actual standard that they can work from.

I am sure that is one of the reasons, another reason can be the price for an integrating sphere and what your get for that price. I.e. your get lower lumens value (than bulb lumes), and that is a problem when lumens is a important specification for selling a high power light.

Same with runtime on unregulated light, your get much more than twice the runtime when measuring it to 1 lumen (or another low value), compared to 50%.

These "inflated" numbers look nice on the package and most people do not known the difference between one or another way to measure, they just get the light with the highest numbers.

A standard might change that, but only if the manufacturers follows it.

 

[SilverFox]

Hello HKJ,

There is no way to control exaggerated advertising claims, however it may be possible to push for more engineering data.

One of my favorite lights is the EternaLight. In the instruction book that came with my EliteMAX there is a graph comparing the lights performance with Alkaline and Lithium cells. It also demonstrates the change in runtime when you run the light in regulation versus direct drive. The graph lacks resolution, so they also include a table that gives you numbers you can compare.

This simple graph allows me to understand how this light performs. The relative light output scale goes all the way to 0, but it is pretty easy to pack 50%. In direct drive, it is also very easy to see that the light output is going to rapidly drop off in the first few minutes of use when using Alkaline cells.

I can also see that when the light is used in regulation, it will eventually drop out of regulation. When it drops out, it drops like a rock. If I am out camping, this becomes a very important thing to know.

This little bit of extra information could easily be supplied by other manufacturers as well. They could set the relative light output scale to a range of 0 - 100% and simply put a few tick marks on the runtime axis and label the maximum runtime to 0%. With a graph, you can back up to 50% and get a reasonable idea of what to expect from your light.

If this information was supplied, we would then have a maximum output number, as well as a graph showing runtime versus light output. The flashlight manufacturer could even pick up a royalty from the battery manufacturers by stating that their results were obtained using XXX brand batteries.

As long as I am dreaming, a beam shoot or two would also be very nice...

I am not sure there is a way to deal with the expectations that the advertisers project, but an educated purchase usually meets more of the expectations than an impulse buy.

Tom

 

[HKJ]

This simple graph allows me to understand how this light performs. The relative light output scale goes all the way to 0, but it is pretty easy to pack 50%. In direct drive, it is also very easy to see that the light output is going to rapidly drop off in the first few minutes of use when using Alkaline cells.

Hi Tom

I agree with your on everything and I also like the runtime graph.
For some other lights they say x hour regulated and y hour unregulated, this is also nice (But not as good as the graph).

Its is a good thing that some people here do make runtime graphs for a lot of lights (A big thanks to them :twothumbs).

Henrik.

 

[2xTrinity]

200 lumens: Is the value out the front of the flashligt or is it from the bulb/led? (i.e. torch/bulb lumens)
xx lumen: When is the lumen output measured: With fresh batteries or with nearly extinct batteries or somewhere in between? This is very important with incandescent flashlights and unregulated led flashlights, and less with well regulated led flashlights.
xx lumen is always measured with fresh batteries as that gives the biggest most impressive #.
Depending on manufacturer this is rated 3 ways.
1) Arc and Surefire send their torches to a lab and you get torch lumens.
2) Calculate lumens based on power to LED and LED chart to get LED lumens.
3) Put the highest # they can find from the LED manufacturer. I can spot these fairly easily. 42 lumens for a Lux1 (~25 torch lumens). 125 lumens for a LuxIII (28-75 actual lumens depending on driver). 900 lumens for the SSC P7 (the currently shipping C bin is 700-800 LED lumens, allow 65-80% transmission through the optical system and I get 455-640 torch lumens. Of course the marketing saw the 800-900 lumens unotainium D bin spec and put it on the torch.

The second method, actually doing a table lookup on the datasheet, isn't bad, though it would be better if they found a "typical" value (not max), then multiplied by a correction factor based the expected optical efficiency of the rest of the system, ie, reflecance of the reflector coating, reflection losses in the window, etc.

runtime xx hours: What is the stopping conditions for runtime: 50%, 1 lumen or ? For some light the difference in runtime can be very huge between a 50% or a 1 lumen condition. Battery often not specified. Interesting for a Fenix L0D NiMH runtime is 3X alkaline while the Fenix E0 or E01 alkaline runtime is 2X NiMH.

There are a few reasons for that. At high load, alkalines are crap -- NiMH deliver their full acpacity. Alkalines only deliver full capacity in lights like the E01 with very low draw. The other is that Fenix reports their runtimes inconcistently between the two. The E01, their runtime refers to moon mode, but in the L0D which is semi-regulated I believe they refer to 50% output.

However, I can tell you right now that the E01 certainly does not produce 10 lumens for 20 hours. Of course, Fenix doesn't even say that, they say
"10 lumens (comma) 20 hours"

based on the white LED lumen testing thread, the Nichia GS produces 7 lumens @ 20mA. in order to produce 10 lumens, about 33mA is necessary (efficiency drops).

Based on review threads, the E01 runs LED at 20ma, or 7 lumens max.
It runs for 10 regulated hours on NiMH with a sharp cutoff after that, or 10 regulated hours on an alkaline with a 10 hour usable "moon mode" after that. So that would suggest that runtime as I would define it (to 75% output) is actually the same for both, not significantly longer for alkaline.



IMO I would prefer fenix actually SAID "7 lumens for 10 hours regulated, usable light for 10 additional hours." Because that's actually significantl BETTER than a non regulted curve, whcih would be 15 lumens for ~30 seconds, and 5% output or less for 20 additoinal hours, that could also honestly claim "15 lumens, 20 hours".

 

[KingGlamis]

Hello HJK,


One of the "secrets" that came out of my discussions was an unusual request from several spotlight manufacturers asking that the light measurements be taken at a specific distance. The lighting lab people were also curious about this, and they discovered that there was a crossover point in the beam, before it was fully developed, that actually registered a higher candlepower at that distance than it did at any other distance.

In this case, a manufacturer could examine the characteristics of the beam, pick the crossover point, send the light to a lab to have "official" measurements done, specify the distance, because there are no standards that would indicate a different distance, and come up with their 2 million candlepower rating, and say it is "verified" by lab testing.


Tom

This beamshot of a "2 Million candlepower" spotlight during a dust storm seems to backup what you posted. I can see the candlepower rating being higher at the point where all of the light converges.

 

[2xTrinity]

This beamshot of a "2 Million candlepower" spotlight during a dust storm seems to backup what you posted. I can see the candlepower rating being higher at the point where all of the light converges.

I agree with what your'e saying, but I'm going to actually clarfiy the definitions of lumens/lux/candlepower.

Lumens - overall output.
Lux - lumens/square-meter or incident intensity.
Candela - lumens/solid-angle. A 1 candela light isotropic (equal in all directions) light source is therefore 4pi lumens. If your light is a perfect point-source, candela is equal to the lux reading at one meter distance, or lux multiplied by the distance in meters squared.

However, the "image size" of that torch is obviously not a point, it's actually the area of the entire reflector, which makes the candela value found by inverse square at the "sweet spot" total BS. If you were to take the lux value very a very long distance away, it will approach an accurate result as the light will start to look more and more like a point as your distance from it approaches infinity.

So a more fair and accurate approach would be to take lux at a very long distance, as far away as you can get while still getting a meaningful result on your lux reader, then calculate based on inverse square.

 

[SilverFox]

Hello KingGlamis,

That's a great shot of the crossover point.

Tom

 

[SilverFox]

Hello 2xTrinity,

I believe that is actually what they do. They determine the cross over point, then go some distance beyond that. Using the inverse square law, they normalize to Lux at 1 meter.

I don't believe the crossover point issues influence lumen measurements, so that could be a good fall back position to take.

Tom