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BlindTiger said:
I'm curious how hot should a LED light get compared to an incandescent flashlight?
It can't be as hot as a surefire. Even the regular p60 bulb gets hot.
I have a first run LS and it never gets too hot. I will measure the temp with my temp gun next time.
Does anyone out there have any measurements?
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BlindTiger,
this is exactly one of my next projects, since I'm always concerned about heating and heat dissipation and other issues. So, while I don't have time vs. temp graphs yet I CAN tell you that the Arc LS, or at least the two I have used (one LSL, one LSH) most certainly DO get as hot, and even hotter than a 2x123 SF light w/P61 run constant on. I have run my P61 for an hour straight, through three battery changes, and it was, if anything, less hot than an Arc LS run constant on, which I have done on numerous occasions.
Most of the wasted power of an incan gets radiated out the front of the light in the form of Infra Red. i.e. it has a "hot" beam, a beam you can FEEL with your skin. In contrast an LED has a "cool" beam, one that I don't think you could feel on your skin, but the trade off is that the wasted power turns up as heat in the die and must be drawn away to the head and dissipated there.
The heat build up in my Arcs has never been an issue; never TOO hot to hold or work with, only something I most certainly notice, and something that I don't enjoy. Also, as has been pointed out, in some cases a light left on and unheld gets hotter than one being held, although mileages vary on this depending on ambient temperature and air flow and so on.
As for differences between LEDs, I can say that yes, each one will generate a different amount of heat, although all of the LS's will fall within a certain range, which in my limited experience is not that broad.
FWIW.