On flashlight output.

Monday, March 08, 2010 Filed in: Self defense, Accessories

I'm too lazy to go look, but I think I've mentioned that I consider the high-powered flashlight to be the most important non-lethal self defense tool one can carry. When it comes to light output, I'm also of the opinion that more is better, and lots more is lots better. When I hit the switch, I want all the light I can get, and frankly anything under 200 lumens doesn't cut it as far as I’m concerned.

Not long ago it came to my attention that not everyone shares my predilection for light. Usually the contrary opinion is something like "that much light causes glare, which makes it impossible to see. Don't carry a really powerful light for that reason."

Poppycock. The issue with glare isn't in the amount of light being generated, it's in the nature of the beam.

If you pull out a flashlight (any flashlight, really) and shine it on your ceiling you'll notice two parts to the beam. The central part, where it's brightest, is called the 'hotspot'. The surrounding corona of dimmer light is called the 'spill'. The hotspot consists of light that is more collimated; that is, the rays are more aligned than the scattered rays of the spill. It's collimated light that causes glare, and since most flashlights have a hotspot most lights will cause glare if the conditions are right.

If something of light color, or of reflective nature, ends up in the hotspot the collimated light will be bounced back to your eyes, which is perceived as glare. This condition most certainly makes seeing things more difficult. The cure, which most people discover right away, is to illuminate such objects with the spill portion of the beam. Those scattered rays dramatically reduce, or even eliminate, the glare.

Most people think that glare reduction is due to the spill being dimmer than the hotspot, but that's not the case - it's because the spill is more diffuse, and less likely to reflect from the object.

If you try out a number of flashlights, you'll find some major differences in the beams they produce. The size of the hotspot varies, as does its definition. Some hotspots have very sharply defined edges, dropping abruptly into spill, while some are more gradual. There are even beams that have no really defined hotspot, in which the entire beam is a flood of relatively diffuse light. Those are the beams that are least likely to result in glare, and thus are preferred for a self-defense light.

A beam that is pure flood, that is to say with no definable hotspot, will light up an entire room with nice, even light. That's what we want to see! It doesn't matter how bright that flood is, as long as there are no collimated beams the incidence of glare will be reduced.

(All this will be old news to any experienced photographers in the audience. They know that you get more glare from a specular silver umbrella than a softbox, and that it's completely independent of the amount of light being generated.)

A flood beam makes it easier to spot threats, and it makes shooting with the flashlight easier as well. That's what "tactical" lights are supposed to be for, correct?

Sadly, the presence of the word 'tactical' on a flashlight's marketing blurb doesn't mean that it's suitable for such use. As it happens, there aren't a lot of flashlights with flood-like beam characteristics. When people look at flashlights they want to know how far it casts a beam, a desire which favors lights with very collimated and well-defined hotspots. A flood beam simply won't 'throw' as far, even though it's a better choice for the illumination of lethal threats. Bottom line: they don't sell as well.

I've been there; up to a couple of years ago, I too was more interested in how well the light illuminated distant objects than how well it illuminated things that actually posed a threat to me. I've learned since then, and today I look for the flood-iest beam that I can get.

Believe it or not, it's tough to find a light that is truly suitable for self defense, which favors a broad flood beam. Surefire used to have a couple of great candidates in the Lumamax L2 and L4 models. Their flood beams would light up an entire room from a doorway, but over the last couple of years the beams have changed a bit as the LEDs were upgraded. (I also suspect marketing had something to do with that, as we've already discussed.)

The L2 and L4 of today have a little bit of a hotspot and thus aren't nearly as good as the older versions, although they're still better than any other "off the shelf" light you'll find. They would be my first pick.

That is, unless you have a Surefire 6P (who doesn't?) or similar light. If so, all you have to do to make it into a first-class defensive tool is to replace the bulb with a Malkoff M60F LED module. It will give you a pure flood beam that, as of this writing, is the best on the market. (It’ll fit the aforementioned 6P, as well as the 6Z, M2 and G2 and perhaps a few others.)

As always, having a bit of knowledge helps you make better decisions. Lumens aren't everything, and just because it's expensive, from a name manufacturer, and says 'tactical' on the side doesn't necessarily make it suitable for defensive use.

-=[ Grant ]=-

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