CPF Scoring Standard

[INRETECH]

There are so many flashlights and other products out there making so many wild claims such as "Worlds Brightest and Longest Operating Flashlight"

I suggest that we describe a "CPF SCORING" value for flashlights, to allow people to describe a score that will easily allow people to compare flashlight brightness and operating time

This would be a two digit number; in the format:

(Initial Brightness)'(Operating time)

Initial Brightness

Initial Brightness is described as the Brightness (In Lumens) of the light as power is applied, using normal store-bought randomly selected batteries at normal room temperature

Operating Time

Operating time is the number of minutes that the light output is greater than 25% of the Initial Brightness of the product

I feel 25% is a fair value that will allow the user to have "usable light output"

For example; a product with a score of 12'250

Would mean that the initial brightness was 12 Lumens, and it maintained more than 3 Lumens for 250 minutes

A flashlight with 4 5mm LEDs would have a lower initial brightness, but have a much longer operating time since the current draw is smaller

Weight = Operating Time X Brightness

 

[NightStorm]

You know, Mike, you will also have to set a battery standard for the duration. You will also have to account for the different power curves between cell chemistries. The CPF standard is a good idea initially, but the variance in technologies may muck things up a bit.

Dan

 

[Sigman]

Of course the "Independent CPF Labs" would have to be established and the "INDEPENDENT" part would have to be enforced to prevent coercion by "less than honest" manufacturers.

Do you think the manufacturers who produce those ""Worlds Brightest and Longest Operating Flashlights" would publish the "ICPFL Rating" if it proved their torch to be inferior? We would have the results available to us, but now how to get those ratings to the public?

 

[INRETECH]

The batteries would be standard randomly purchased store-bought alkalines at room temperature

They might not want to publish the CPF-score, but if enough people ask them - they might start putting it on their webpage/products

 

[Monsters_Inc]

2nd bit should be half brightness, as it's more scientific convention (eg half-lives).

 

[JohnG]

Regulated power is another issue.
Current regulation is held in high regard around here and I suspect many would consider replacing the batteries of a torch long before the 25% level of brightness was reached.
The rating system you have proposed, however, would make certain unregulated lights look extremely good...

 

[brightnorm]

Originally posted by PercaDan:
You know, Mike, you will also have to set a battery standard for the duration. You will also have to account for the different power curves between cell chemistries. The CPF standard is a good idea initially, but the variance in technologies may muck things up a bit.

Dan

<font size="2" face="Verdana, Arial">Agreed, because W = OT x BR doesn't work when you use different battery chemistries in the same light. For ex:

UK 4AA / Alkalines W(5.3oz measured)= "6" (arbitrary assigned brightness #) x 3.75 hr (approx runtime))

As opposed to:

UK4AA / Lithiums W(3.8oz measured) = "7" x 5hr (approx runtime)

Which would yield a seemingly contradictory result

Brightnorm

 

[Tomas]

1) Batteries should be standard batteries of the type recpommended by the manufacturer.

For example, there are no "alkaline" 123's to my knowledge.

2) Light output is more complex than just "X lumens." It requires knowing beam width, distance from target, and whether it is an area average or simply peak point intensity.

I have a laser that puts out a very narrow beam at very high intensity, I also have a tiny florescent that puts out about the same amount of light, but in an essentially spherical manner.

Beam width is generally considered to be two times the angular distance from beam center to the 1/2 power point. Another possible way to measure would be to consider "beam area" which would be the total area that is greater than 1/2 the intensity at the center of the beam. This allows for beam shapes other than circular.

3) The cutoff point is very complex.

Considering lamps with regulators may drop from their full intensity output to a much lower battery conserving mode as voltage is reduced, and that their conserving mode may be above 25% intensity, one needs to determine battery life in a more complex and conservative manner than initially suggested.

The time to reach 1/2 intensity would possibly be better than the 1/4 intensity recommended, but in either case a light could be simply engineered specificly to "test well."

Extreme examples would be a light that ran at full intensity for a very short while (5 minutes?) then dropped to 51% for an extended run time as opposed to a light that regulated at full intensity until there was not enough power left to run the regulator.

Assuming they both started at the same intensity, the "short bright then drop" lamp would get fantastic numbers, even though it would be less usable.

Overall, I like the idea of some sort of rating, but it needs much more detailed thought on how to measure, what to measure, and what the purpose of the light is.

For example, "moon mode" (assume 1/4 to 1/2 intensity) when the battery reaches half-life may be very sensible and practical in a light for close in work, but ridiculous for a long-throw unit.

Then again, a "moon-mode" might useless even on the close work light, depending on it's job.

Now, all you REAL flashlight people out there, get your heads together - I've only even paid attention to this whole scene for a few months, and none of my background is in lighting ...

Take care,

 

[Charles Bradshaw]

Store branded Alkalines, rather than premium brands AKA generic. For 123s, Sanyo or GE-Sanyo, since they are the cheapest to be had, that I know of.

Lights that take advantage of Lithiums like the Inretech adapter and CMG Reactor, are of course, stuck with Eveready L91s.

We would need to note whether it is regulated or unregulated, LS, Nichia, Krypton, etc.

Perhaps a rating for versatility in configuration.

Great idea, Mike.

Objective analysis is required, rather than personal likes and dislikes.

 

[INRETECH]

I will try to address the points - my comments attached:

1) Batteries should be standard batteries of the type recpommended by the manufacturer.
---
Yes, the flashlight would be tested with the batteries it was designed for and no "specials"
A flashlight designed for Alkalines would run store bought - not "selected" Alkalines, not Lithiums - and all tests would be at room temp of 68F

2) Light output is more complex than just "X lumens." It requires knowing beam width, distance from target, and whether it is an area average or simply peak point intensity.
---
I am trying to just establish a simple not perfect scoring system, the lights would be measured at a fixed distance for all lights which would be fair for some, and "unfair" to others - but we need a standard

Yes, it will make some flashlights look great and others "not so great", too bad

As to your comment about laser-pointers, the CPF-Scoring would apply to flashlights only, not laser pointers

3) The cutoff point is very complex.
---
Quite the contrary - its incredibly simple
and that is why I think it should be a fixed percentage of the initial light output instead of a fixed light output

When a person buys a high powered flashlight, he/she expects it to put out a lot of light, if they purchase a smaller flashlight - they expect it to put out smaller amount of light

Take the initial brightness, multiply it by 25% - and see when the brightness falls below that result

Someone could design a flashlight that uses a 5w Luxeon on a 9v battery; sure it will give a incredibly high first number; but the operating number of minutes (or seconds) will be very low' for good or bad - the customer needs to know that fact and allow him/her to judge from there

You draw the line on the sand, and thats it

I would like to see the CPF-Scoring system be a "sticker" that is put on the product like the sticker on a new car, tell the user the "Miles Per Gallon" and let them decide; they know that a big SUV is going to have lower MPG than a little enconomy car; but they need the numbers to let them decide - a fixed, no nosense grading system with no favorites for all is the most fairest

I've only even paid attention to this whole scene for a few months, and none of my background is in lighting
---
I worked in the lighting industry for over 15yrs
We published the number of lumens on our fixtures and let the customer decide which one is best for him/her

 

[webley445]

I find the related experiences of members to be helpful. Covers all spectrums, good and bad, and varying outlooks/opinions, and differing operating conditions.

 

[INRETECH]

You are right - unfort, unless the public demands something - there would be no policing; nothing like UL - so for right now, its that old saying "Let the buyer beware"

I am very aware of the Luxeon parts, I have seen some that are so bright I don't want to turn them on again (get the Dalmation Effect) and others that are "so so"

About testing, I also agree that it would be best if someone ind. did these tests, like LightCrucial or Craig of the Led Museum (When he recovers) and publish the CPF value as a number on his report - since most of the companies would "skew" the test for their favor

Its just like when Motorola and Intel used to publish performance claims about their microprocessors using Benchmarks; each one would say that the benchmarks were not fair - and they would "adjust" them, and of course - their product always came out better than the other

I am just trying to work on a standard that companies could show some idea of brightness/life instead of these meaningless claims "Worlds Brightest Flashlight"; people want numbers to allow them to compare products and performance

In the Ham Radio field, we have the same thing - companies advertising their antennas have a 50db gain, and we ask "over what, a wet noodle ?"

Cars have a milage sticker on them
Hot water heaters have an eff sticker on them

 

[star882]

We should have a CPF score for each type of battery.
Example: alkaline:17'200 NiMH:17'170 lithium:17'450
Maybe add runtime graphs so it is not possible to cheat by making the light so that it is bright for the first 5 minutes, then dimmer but still above 25% of the initial output.

 

[webley445]

I find that by going between the various review sites [LED Museum, Lightsite, etc.] I get a pretty good picture of a lights performance. And they give you beam shots at published distances, although they may not all be the same. I like seeing the beams at different distances.
Personal experience helps alot, owning, using, a light lets you know what it'll be like if a light is reviewed as brighter or dimmer than what you own. And besides, most here start getting into it and will buy more than one light. You need a couple to fit different tasks.

BTW hats off to those who maintain independant review sites. I for one and many, many others appreciate what you do.

 

[INRETECH]

The comment was

"We should have a CPF score for each type of battery. Example: alkaline:17'200 NiMH:17'170 lithium:17'450"

Yes, that is fair - allow the customer to see the possibilities, let him/her decide to "turbo" the flashlight by spending a little more on batteries

I have only done tests on our products for operating time:

www.inretech.com/batlife.htm

We have a very nice digital recording light meter, and I have used up a LOT of batteries doing these tests; but they showed us a lot of information about performance

As time permits, we might do the same tests (same rules) on some of our competitors, and publish the results - good or bad

 

[Slick]

Well, I for one, favor the good old fashioned "consumer based flashlight shootout".

IE: customer buys a couple of flashlights, fresh batteries for each, then conducts their own tests. Test methods are described, and results of the "contestants" published by the tester.

These are the most meaningful comparisons that I have read. What helps is for various "tests" to be performed using accepted constants - like measuring lux at exactly 1 metre..etc.

Test constants are more accepted when they are easily understood by both reviewers and testers. Sometimes I will read a test where I don't fully understand a test or the reasoning behind it, and not derive any usefull information from it. Simplicity Rules..

 

[Alan]

IMHO, brightness/runtime chart is a must for comparison. The chart should be in an agreed format yet provides meaningful and understandable data. A skillfully scaled chart could be misleading.

Alan

 

[Saaby]

This is a CPF standard right? So why not let CPF enforce it. Sony can't decide their new audio amp is UL listed, Underwriters has to.

So here's what I propose:
We decide on a standard. I like the initial preposition but it does have some flaws. Perhaps, much like the EPA differenciates between city and highway, we could show weather it's regulated or not. Maybe instead of a % of total brightness we could establish a set standard...half a lumen? and go from there...

Say our cutoff point was 5 lumens, Flashlight x's inital brightness is 25 lumens. 5 is 1/5 of 25 or 20%...so when (On a runtime plot) it reaches 20% (Or ~5 lumens) that would be it's runtime.

Ok...so I've been writing this and I think we'd have to have 3 categories...Direct Drive, Fully Regulated, Partially Regulated. We could use slightly different rules for each of the 3 categories--IE runtime on an Opalec conversion (Full regulation) would be until the steep dropoff. Direct drive and partial regulation would have almost the same rules...as their discharge curves are almost the same.

The "weight" could be published--but only with the other numbers...

So here are some examples, real flashlights--made up numbers.

Opalec in a MiniMag:
12'08=96F
or just 12'08F

Arc AAA
4'09=36P
or just 4'09P

and then Brinkmann LX
30'01=30D
or just 30'01D

I hope you see what I mean even with my made up numbers

-------
Would operating time be in hours, with decimals, or minutes?
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Batteries: Let's decide on a standard and stick to it. I say Rayovac Maximum Pluses for AAA,AA,C,and D because they're cheap but work well. We could use anything though--but lets be consistant. All Energizer, all Duracell, whatever...consistancy is the key. Must be fresh!

-------

Balancing all this:
How many people around here have facilities to test lights? Lets establish a standard testing methood, then everyone who wished to preticipate will do at least 2 trials. Submit both. Whoever want's to track this will collect everyone's trials, throw out the high and the low, and average the rest.

----

Final thoughts:
What about a light that's bound to be tested time and time again? Such as the Arc AAA? The CPF score would have to have a revision date...so the final scoring standard I propose, what you'd see on the box would be this:

[Init. Brightness]'[CPF Established runtime][F,P, or D]

---------

Now, mod geniuses...just promice that you won't make a light that is switchable between regulated and direct drive

then we'd have to publish 2 scores

..er, I mean,

:nudge: :nudge:

 

[INRETECH]

No, the rules should be the same for each type of flashlight - this would show the eff of the LED and the manner it was driven

 

[Saaby]

Inretech...I don't know exactly what you meant, but I am going to have to disagree.

This is a CPF standard with CPFers in mind right? Well as far as battery life rules are concerned--who on CPF is going to keep using a Opalec after it's fallen off it's cliff? Even IF it is still providing enough light to make the "runtime" number keep going. If it's NOT this way, what would stop a manufacturer from tweaking a regulation circut to drop off earlier and then run in that low power mode longer to make a nice, healthy runtime number?

About the lettering scheme, lets look at an example...a Photon 1 and an Arc AAA.

The Photon 1 would have a higher "Initial Brightness" score--but would be direct drive. The AAA would be lower initially, but the fact that it's partially regulated would show you that it's discharge curve would be flatter.