we get it, your smater than us, while all your technical lingo is appreciated, itd be nice to know what you think the lumens will be on this light.
Uhm, well, I didn't want to appear smart. There is nothing "smart" in what I wrote. The symbols and the nomenclature probably may look complicated but they are not. It is also quite possible that what I wrote doesn't make much sense and someone more knowledgeable will come here to correct me
I wrote about the thermal resistance - a parameter that tells you what's the temperature difference between two things if one watt of power is generated and and transfered as heat outside. If for example it is 10 deg.C/W and 5W is dissipated, the difference will be 10[deg. C/W]*5[W]=50 deg. C. The junction to ambient thermal resistance basically tells you how hotter the insides of the LED will be than the flashlight surroundings. The LED has to be kept below some temperature for the light to operate correctly so by looking at it one can try to see how much power the LED can consume and how bright it can be.
I assumed that all the energy ends up as heat. I also completely ignored what happens to the heat when it reaches the surroundings. If the light is actively cooled it is not a problem, if it is kept in the hand some amount of heat can be dissipated but the ambient temperature will probably be ~40deg.C - 50deg.C, if it is left alone it can easily overheat. My calculations were here just to continue the heatsinking discussion started by MrGman so I thought we can start with it.
What is complicated is the actual value of the junction to ambient thermal resistance. I don't know that but I though MrGman may have some estimations after all his IS measurements, so I asked.
i dont have a clue what their talking about either. All i care about is HOW MANY LUMENS is it!
I'm just playing with numbers here so what I think may end up being way off from what is real. There are many people more qualified to answer this question. If what I wrote in my previous post is close to the truth, the light would have around 1000 LED lumens and thus around 550-700 OTF lumens, depending how well the LED is cooled. It is, btw, the light from Badbeams3's game, if OTF lumens for MC-E are assumed, although it will probably run shorter than 1 hour (but the MC-E version also will)
EDIT: To clarify, I think that if the MC-E light in the game does not overheat and can sustain 500lm, the SST-90 should be able to put out 700lm. Previously I also calculated LED lumens, not OTF, so it may end up a little better.
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