0.7 lumens? How much is that?

I'm looking at the Surefire L1 - the low run time is very impressive at 3000 minutes. Might be nice during an extended power outage to keep you from tripping over furniture. How bright is that though - got any comparisons?

Also looking at the L2 - good runtime at 1080 minutes on low, a much brighter low at 15 lumens and a lot more max brightness. It's bigger though, but about the same as my EDC L4.

Mike

The L1 on low is a little dimmer than a ARC AAA, but it's in that ball park.

The regulated runtime of the L2 on low is more like 8 hours (480 minutes?). The L2 on low is about as bright as a Luxeon I at 400ma. I sold my SL Jr Luxeon, but I think the SL Jr Lux would be brighter than the L2 on low, but IMHO in use it wouldn't matter. The L1 is about the size of your L4. The L2 is about the same size as your SL Jr Luxeon.

The L1 is nice. I've got a red LED version, that I use for astronomy. In a dark location, (i.e. the site I use or a power-failure) the low-beam of the L1 is plenty. If there's any stray light (say, out on a typical city street), you probably won't see the low-beam at all.

The L1 seems to be optimized for throw - which surprised me a little. It has relatively little spill compared to an L2.

The L2 is a little bit larger than a mini-m*g. The L2's largest diameter is virtually the same, but the body is a little thicker. It's about ~1/4" longer than the mini-m*g, if that gives you any useful point of reference.

The low-beam on the L2 really lights up a room. It is definitely not as convenient to carry as an L1, but it's still not too bad. On high beam, it's crazy bright.

The L1's low setting (0.7 lumens) is about right for reading and keeping you from tripping on things. The high setting (15 lumens) will light up a small yard or campsite pretty well. But, for me, 15 lumens is almost too bright to do something like read an electrical panel or fix something up close.

More light, like 60+ lumens, is handy when you are moving in and out of well-lit areas and don't have to do any close work. That is what you need to see something across a small street under the streetlamp.

I used to EDC a 65-lumen light, but swapped it for a 15-lumen light because it was too bright for most of the things I did. I grab a brighter light for those other times, and am considering an L2 to replace my rechargeable Mag.

Scott

Of course, you can't please all the people all of the time, but if I could snap my fingers and have my way, the low would be at least twice as bright, maybe three times. And the high power would be about the same... Maybe even slightly dimmer for a bit more runtime.

One way to estimate how much you want would be to take advantage of the fact that radiated light is an inverse square thang.

Say you have a Surefire G2 and really like the way it lights up things at 25 feet with its 65 lumens. Maybe you want to know how much light will be required to have the same level of brightness at, say, 2 feet.

So you have a distance for the given light (Dg = 25 ft), an output for the given light (Og = 65 lumens), the distance for the required light (Dr = 2 ft), and you need to know the output required for equivalent brightness (Or = unknown).

You start by setting the intensity of the given light (Ig) equal to the intensity of the required light (Ir):

Ig = Ir.

Now, note that intensity is output divided by distance squared,

I = O/D^2

and substitute to get

Og / Dg^2 = Or / Dr^2.

This can be rearanged to find the required output directly:

Og * Dr^2/Dg^2 = Og * (Dr/Dg)^2 = Or

So:

(65 lumens) * (2 ft/25 ft)^2 = 0.4 lumens.

Translation: You need a half a lumen at 2 ft to equal a G2 at 25 ft. Put another way, an L1 on low is brighter at 2 ft than a G2 is at 25 ft.

It gets a little more complicated than that, but the above should be a useable approximation.

OK folks - I have a good feel for how bright it is - sounds about like my Infinity, perhaps a slight bit dimmer than my Infinity Ultra - both of which are very useful lights. Thanks! Now all I have to do is make up my mind which I want. I know, the standard CPF response to that is "buy them both" /ubbthreads/images/graemlins/grin.gif

Mike