We've all probably seen some fantastic, hard-to-believe claims on the Internet about flashlight lumen output. Some are absurd while those that seem plausible pass under the radar undetected. But even some of those are "Internet Lumens" nonetheless.

Since I very much appreciate truth-in-advertising as a consumer, I figure I owe it to my customers to represent the products on the EDCLB website as accurately as possible. I was a skeptical of some of the output claims on the Lumens Factory heads that I use, so I made a $35 investment in a low-cost yet well reviewed lux meter, and another nine bucks on a styrofoam cooler from Ace Hardware to make a redneck integration sphere (box in my case).

The key to testing lumen ratings is to have a source light of know and proven output, take a lux reading and then divide the lumen rating of the reference light by the lux reading from the meter to arrive at a correction factor. Since Malkoff is a known straight-shooter on their flashlight output specs, I used the BGV2 Bodyguard, E2HT and E2XTD heads to see if the lux readings divided into the lumens rating yielded a consistent result. Low and behold, each of the three heads resulted in an identical correction factor of 4.38, which is the factor I use. This correction factor is multiplied by the lux reading on the meter to estimate the lumen output of the light being tested.

Here is my very high-tech set up;

The "cooler of truth" confirmed my suspicions - the ratings of the LF heads are a bit optimistic. For example, the 3-LED head used for the E1 Admin and E1 Inspector has a claimed output of 900 lumens on high, which struck me as a bit ambitious for a single CR123 power source. The Cooler of Truth revealed that number to be 500, which is WAY more plausible. The single mode head used with the E1 PSE was likewise revised downward from 550 lumens to 450 on a 16340 Li-ion cell, which it can do reliably. I also took readings on these heads powered by a single CR123 and published separate output specs.

Conversely, the Streamlight 2L-X measured exactly the same on both a set of CR123 batteries and an 18650 Li-ion cell. Streamlight rates it 500 lumens, but my measurement puts it at 600. Immediately measuring my Dagger (rated by Malkoff at 500 lumens), it calculates at 499 lumens.

So while these measurements are not laboratory grade, I do have some faith in them, and they do help confirm what I discern by eye in side-by-side comparison. Most importantly, they help me represent the performance of the lights on EDCLB as honestly as possible.