Question regarding thermal step down

LED Flashlights – General Info
1

I’m looking at the Surefire edc2 dft. I really like it. I know it’s pricy and Im aware of cheaper alternatives, but I really like it.

I’ve seen multiple people measure the output and it’s coming in anywhere from 70k-95k, but can only sustain that for less than 2 minutes.

I’ve emailed surefire days ago they have not responded.

What I’m trying to understand is, the light stays on high (700 lumens) for two minutes before stepping down to half the output, it has around 80k candela measured on high,

My question is, when the lumens drop to half does the candela drop proportionally? 40k?

Also, how many 80k bursts can I get out of such a light, is that dependant on battery voltage , for example as long as the voltage is above 3v the light will give me 80k candela, or is it more dependent on temperature?

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Your thought process ia good but I dont think the numbers work out that way.

Thermal stepdown is supposed to prevent self destruction of the light.

Half the lumens does not mean you can see half as well.

On a light of the caliber you are looking at it, the stepdown will be less obvious than on a $20 Sofirn.

Someone else on the forum can probably explain it much better than me.

3

yes, lumens and candela decrease on a 1 to 1 ratio

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4

For $250+ if you don’t mind saving $100, take a look at the Olight Warrior X4. I tested it and it positively trounces the Surefire in every way shape and form. Just saying.

For the step down-yes, as mentioned candela is proportional to the Lumen output. How much depends on the battery capacity, driver regulation, heat saturation. More or less a well regulated light with a high capacity cell can re activate the highest setting over and over for quite a while with slight drops in output after a while, and shorter duration of brightness in between.

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5

I have always liked Surefire lights. I have a few very old incan ones. They have proven to be pretty darn bullet proof.
But today, you can definitely get more bang for the buck from several manufacturers.

But all of the good ones will step down. They have to in order to protect the LED and electronics. It is all a matter of degrees. Most very high power lights are lucky to get 30 seconds at full output.

Are you having problems with any specific task when the light steps down? Or is it one of those, “just a matter of principle” things?

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Principle and toughness

I don’t trust olights I’m aware of them, I just don’t trust them