I meant in post 493, the middle light. In reference to the basen, someone gave it to me but the ones I’ve been seeing don’t seem legit. Liion wholesalers has the 4500mah basen in stock
Thanks for sharing these figures. I am probably going to draw fire from saying this. TBH, I am a bit underwhelmed and disappointed that the lumen outputs will drop below 1000 lumens in less than 2 minute? Is this behavior due to timed stepdown? Since this flashlight has more mass compared to the D4, which should help it to dissipate heat better, I was hoping it should be able to output half the max lumens for sustained period.
Are the figures similar for the other LEDs: XP-G2 S4 and XP-L HI ?
There is no timed step-down; it regulates entirely based on temperature.
Nichia 219c generates more heat than the other emitter types, and has the lowest sustainable output. Also, I don’t know maukka’s test parameters, like if it involved any cooling to simulate the effect of holding the light in one’s hand, or how its thermal settings were configured. However, maukka has probably the most accurate lumen measurements on BLF, so you can count on the numbers being good.
Here’s what I got with XP-L HI, with the thermal ceiling set to a comfortable and calibrated 45 C, with light air cooling from a fan:
If you want it to stay brighter, you can raise the temperature limit or add external cooling. Like, put it in cold water or hold ice against the heat fins, and it’ll stay at the highest brightness the battery can manage.
TK, thanks for this. I had wrongly assumed Nichia 219c would generate the least heat based on its lowest lumens output. Ideally I like the sustained output as I normally go out at night for 30 minutes walk, and it will be nice to have the light at the same level of output the whole duration of the walk.
What is people’s opinion on what temperature is still considered comfortable enough to hold the flashlight? 50, 55?
ssschen, that’s going to be a subjective thing… you’re going to have to set it at what YOU are comfortable holding. I mod lights virtually daily, machine aluminum and copper on the lathe… my hands are so used to extreme heat that my idea of comfortable to hold is going to be much different than a lot of peoples. Almost like asking what pepper is too hot to eat, depends doesn’t it?
Making 5685 lumens and 5171 lumens, respectively. Both from Sony VTC5A cells.
For clarification, both of these are made with the MCPCB and Optic that Hank designed/chose for use with the Emisar D4S. Both of these are running Bistro from an FET+1 driver.
Depends how long you hold it. Slow burn is a thing. And it’s insidious as you don’t feel it until long after it’s done. There are people who got burns to their legs from using car seat heaters in warm weather. I once burned myself lightly (no damage but skin was sensitive) by holding a warm soup bowl that never actually felt painfully hot. I just held it for a fairly long time.
Okay, in that case it stabilized at a higher output than I would expect. With no cooling or heat sinking, I figured it would settle lower.
During tests I generally have a fan blowing at the light, from 1m away, at the fan’s lowest speed. I’m not sure if this is a good way to simulate the heat-sinking of a hand, but it does at least make a pretty measurable difference compared to stale air. My thermal testing is pretty imprecise though.
This may have already been discussed earlier. But is it possible to mod the light to a different aux led? I don’t love the blue. Would much rather green or even red. Is this doable?
Here’s what the AUX LEDs look like on the meter. This is with the optics and a slight Zircon minus green on top so on the CIE graph the LEDs would actually sit just a bit higher.
Regarding the step-down rate. Keep in mind that if you don’t start on turbo, you should have longer before the light steps down from your initial output levels.