how is Surefire lumen count measured?

Hi fellas:

Perhaps some of the SF insiders can enlighten me here:

when surefire publishes a lumen rating, that is the lumen count from what comes out of the reflector and lense, right? the TL-3 thread comfirmed my suspicion of the Strealights using raw, peak bulb output as a claim to be more powerful. Not that i dislike them, they are still wonderful lights, but i am so much more in favor of the way surefire does things, where they publish the average output, rather than the peak, for their specification, so the last thing that i want to comfirm is that the rating is based on what comes out of the bezel, right?

Case in point, the TL-2 makes "100" lumens for one hour, where as the 6-P makes 65 lumens" for 1 hour, althought the difference looks staggering, the surefire's peak output is much higher than 65, i'm sure.

same thing goes for the TL-3.

Just a little thought to share with y'all, hopefully someone can knock me on the head and say "duh, of course SF uses the reflected light count, what else would they do?"

have a good thursday out there.

Nick

Not only that, SF publishes average lumens not peak lumens. Average of what comes out the front end. It's on the other side of the scale from manufacturers who publish PEAK lumens, and take the peak of what comes out of the bulb. Shame, shame!!

I have seen many lights with "TWICE" or even more "lumens" lose out to a humble E1e with MN01 - 15 lumens. I'm not the kind who favors SF to the exclusion of all else, but if other manufacturers were honest, I'd like their product a lot more. Arc was very honest about their lumen rating (all 3lu from the ArcAAA), CMG Equipment and Photon don't make outrageous claims about their lights, so it's all good. Not an exhaustive list, just those I have had to work with.

There is no standard - no guide to which flashlight manufacturers can claim their output/runtimes have been tested in accordance with. Therefore there are few testhouses and the equipment is expensive and not purpose built.

With the introduction of LEDs that can rival incandescents for output and intensity, new machines for measuring LED light output have to be used.

If, and this may be a bigger 'if' than many realise, if, flashlights from the same manufacturer (or supplier) are measured using the same techniques then they can be compared to each other.
However, since flashlight companies usually don't publish their test methods and results it is very difficult to compare flashlights from different manufacturers based on their own ratings.

One of the really useful features of CPF is that as a community, we have a wide variety of lights and there is usually somebody with the lights you want to compare who can post their opinion based on the individual lights they have.

Al

I have relied heavily on Quickbeam's Throw/Output chart on Flashlight Reviews. To me, it is a great resource--you get a direct comparison of output and throw for many flashlights. The L4 versus the E2e is interesting (better output but shorter throw). The Stinger (at full focus I believe) against the M3 also (less output but longer throw).

I have been using the chart to assemble my own mini list of flashlights with the best output or throw for their size. The Stinger, Strion and E2e seem to be good for throw. The M3, M2 (P61), L4 and TW4 seem to be good for output.

Of course, this says nothing about other qualities, but is a good starting point so you aren't fooled by apples to oranges comparisons by flashlight manufacturers.

I think all flashlight manufacturers have things to answer for in their advertising.

I see LCD projectors use "ANSI Lumens" measurement, which has at least a defined measurement method. I guess flashlight industry may use somthing similar like this? However Projectors can creat a perfect square light projection, while flashlights have sidespill going on... /ubbthreads/images/graemlins/confused.gif

What I found from a quick yahoo search;
ANSI lumens is a measurement of the overall brightness of a projector. Because the center of a projected image is brighter than the corners, ANSI lumens is a more accurate representation of the image brightness than lux (one point on the screen). ANSI lumens are normally measured by dividing a square meter image into 9 equal rectangles, and taking a lux (or brightness) reading at the center of each rectangle. Taking the average of these nine points gives the ANSI lumens of the projector.

ANSI requires that if you use an ANSI spec for anything, that all the specs must be ANSI. Surefire rates the runtime of some of their lights as ANSI runtime, therefore, the lumens have to be ANSI lumens for those lights, else they are violating ANSI terms of use.

rsilvers said:

ANSI requires that if you use an ANSI spec for anything, that all the specs must be ANSI. Surefire rates the runtime of some of their lights as ANSI runtime, therefore, the lumens have to be ANSI lumens for those lights, else they are violating ANSI terms of use.

Click to expand...

This thread is 8 years old so there was no ANSI standard for lights when this was started. The first SFs that I saw with ANSI FL 1 labels were the G2X and 6PX series of lights but don't know for a fact if they were the absolute first.