Continuous Runtime : need your advice

Ok -- you may say that I actually need a lantern... but I need a good-size light, preferrable surefire-based platform that could be used as a "lantern" or extended and continuous "bright-enough" light. /ubbthreads/images/graemlins/smile.gif

Most of my bright lights -- the 5W Stock-L4, 5W-TnC HLV, PRT-3W/DB917, KL1/3W/700ma, does suffer from excessive heat when run for 5-to-10 minutes. Yeah, SF are tactical lights, but I'm making them as general purpose for my usage /ubbthreads/images/graemlins/grinser2.gif

I am currently using the stock KL1 with Pila for this purpose. This is my bright enough light but tint is less than desirable by my current standards ( with all the other lights I REALLY could compare).

I once owned a KL3/PRT/3W/1200ma by Chop (Where is Chop?). My friend "bought" it away. Although I like the light, the PR hotspot seemed to be quite narrow for me for medium range and general illumination.

Can the 5-Watt be tamed to provide medium hotspot and a LOT OF sidespills?
I would like to run it with at least a Pila voltage (3.7) to 9volts. No single CR123 requirement.

Which Lux should I use -- 3W or 5W?
How do I regulate? -- voltage input would be 3.7v to 9v
My "power pack" -- SF-E2/BE3-series or SF-6P/9P-series
Environment -- mainly as indoor general lighting, at rare times as outdoor walk light.
Light Output -- "KL1 was near good enough, but tint is not desirable". Medium hotspot with a lot of sidespill.
Runtime -- 2 hours continuous, hanging or hand-carried; heat should be manageable. /ubbthreads/images/graemlins/blush.gif

Please post your suggestions and possible options...

Next-generation KL1 using Lux3 emitter, when it comes out and when it's confirmed. Tint should be a lot better. Newer KL1s are not bad, and I believe same goes for newer stock KL3s. The 5W could probably be fixed with some satin tape or scotch tape as an inexpensive beamfilter. 5Ws typically do not run for 2 hours though.

Extreme case: U2 Digital Ultra, dial up as much light as you want /ubbthreads/images/graemlins/tongue.gif

Do you have an E1E body to run your KL4 on? If it works (i.e., if the vf of your KL4 is low enough), it should meet all your requirements. Stays cool, almost as bright as a KL4 on 2x123, long running (brighter than the KL1 for the entire two hours, I'd imagine), good "flood" beam. Oh, just saw that you want to use the E2 "power pack" - maybe use a dummy 123 (or a wad of tinfoil) to run on one 123? Or run it off the Pila - best of all worlds.

John

KevinL> I actually like the light output of KL4 as it is, but hate the heat. /ubbthreads/images/graemlins/blush.gif

kubolaw>
John, I have a TW4. I don't mind running DD with CR123, but I'm not so sure about overall runtime. I would like to maximize the use of my Pila rechargeable (and extending my 'battery budget') -- Pila does put my KL4 into regulated mode (again the heat does matter)... /ubbthreads/images/graemlins/sick.gif

An underdriven 5 watter coupled with a 17mm reflector makes for a nice flood. If you run it at 500mA or less, heat wont be a problem.

[ QUOTE ]
akula88 said:
KevinL> I actually like the light output of KL4 as it is, but hate the heat. /ubbthreads/images/graemlins/blush.gif


[/ QUOTE ]

Yup, that's what keeps me away from an L4 as well. I would love to have one but I keep hearing things about thermal management. I'd suggest you try a larger bezel 5W like the L5 because it sinks heat better, but I don't think it would provide you the runtime you want either.

I'm thinking you might be better served by a custom head, perhaps maybe a BB400 or 500 with an underdriven 5W Luxeon. It would of course put out less light than your current solutions (more than the KL1 though), but it would also solve the heat problem. If you need a lot of flood, you could sputter the reflector or try an optic - not sure how that would turn out though.

Also, ive found with the 5 watter, a DB runs much cooler than a BB driven at the same level.

my micro light i made for this weekend is very close to the sweet spot you are looking for... overdriven lux 3... starts at about 4.7W quickly drops to about 3... i'll have to do another test to see what the power level curve is.

run from one LiON battery... and a small amt of inline resistance will probably get the runtime well over 2 hrs and keep that initial burst of power and heat down as well.. (even when standing alone, heat never gets too hot to handle)

-awr