haha yeah I was looking at the Deft EDC lights and was very excited because it was pretty much what I was looking for............UNTIL I saw the price
Now I'm second guessing the 18650 choice, and thinking of sticking with AAs since I already have 12 eneloops and a chager, and will buy more batteries in the future. How are 18650s in heat situations? The light on my belt under my firegear can get to about 150-180F, and the one in my pocket in my firegear can get to about 250-300F or over. This is what makes me second guess using 18650s and want to stick with the AAs.
What is the "throwiest" single and double AA lights?
One thing I'm sort of confused on is: The Fenix LD10 is listed at 100 lumens while the JetBeam BA10 is 160 lumens. But many posts people say that the LD10 is brighter and more concentrated beam. Is there something else I should be looking at for brightness other than lumens (I understand this doesn't necessarily mean the light "throws" well, just the brightness)
Thanks!
Lumens is like gallons of water per minute out your fire hose.
If you make the aperture smaller (Put your thumb over the end of the hose, etc...), the same GPM will shoot out further, because the same volume has to fit into a skinnier package, etc.
So, "Brightness" has no technical meaning per se.
What you want if you want a tight beam pattern is to have MOST of the lumens produced illuminating a small area.
The amount of light ON a surface is typically referred to as LUX. A surface lit by moonlight is typically rated as around a quarter LUX (0.25) but of course moonlight is not the same everywhere or every night, etc...that's an average.
😀
A tight beam has a lot of lux on a small area, and not much LUX on the rest.
If you have 100 lumens as a source, but concentrate it into a tight beam, most of that 100 lumens is turned into LUX on a small target...call it 10 LUX at some 1' round target face....and no lux around it (Circle of light with darkness around it...a more or less perfect albeit theoretical throw)
For the same 100 lumen source with a floody beam, you might have only 1 LUX on your target, but the circle of light illuminated at 1 LUX might be 10' instead of only 1', and there might be further areas with less than 1 LUX surrounding that as well, etc.
So, your hose sprays out the same amount of water, but you can make a puddle 1' around and a foot deep, or 10' around and a few mm deep, and so forth.
Some patterns have three parts...the hot spot (The bright central spot of light), a corona (A ring of less bright light around the hot spot), and spill (Light around the corona that is not focused).
Depending on the use, all three parts can be useful. A cop running after a perp might want a great hot spot, but he needs at least decent spill to see where he's going/not trip on stuff during the chase, etc.
Hope that helps!
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As for the safety of Lithiums in firefighting...I know they are in use in lights at fire departments - but I also thought that if the cell got too hot it might start to boil the electrolyte, etc. Someone probably looked at this issue, but I'll ask my buddies what the story is on that. Primary batteries can also catch fire, not just rechargables...but I have not heard of fireman having lights catch on fire from it either.
It may just be a case of how long it takes to raise the temperature enough to be critical...and whether any one reaches it in practice.
