i4000R and E4K are both 25 second timer stepdown for their turbo modes
T4K is 10 second timer for turbo
I don't think they qualify as 4000 lumens steady. That doesn't seem possible right now in a 21700 light but I'd love to see if you can find one. AFAIK the best performing 21700 light is the Zebralight SC700d that can probably hold close to 3000 lumens (but only in extreme cold) for ~25 minutes.
Hmm, yeah, 10 seconds is still at the level of a novelty. 25 seconds isn't great, but seems like enough time to get a variety of actual tasks done. I really like how low the SC700d's can go, but the UI seems like it too is trying to put too much into one button, even after setup/configuration.
i don't see how a light that size passively cooled in air can output 4 klm steady with the current state of technology.
I really should've used more detail than "steady." That's my bad. I meant an output level that's intended to be practical and not just a talking point, like the TM10K which is limited to 7 seconds at a time, and another light I don't recall that can handle its max output only for a few seconds and then you have to top off the battery before it can do that again.
A Surefire putting 4000 lumens out the front? Really? Even if they DO have one it will easily fetch a dollar per lumen.
I know Klarus makes a couple that claim 4000 lumens or close...and their XT series uses what is almost the best UI out there in my opinion. I would have pushed Klarus lights more had they developed their latest system a year or two sooner and I had known about it.
But yeah, seriously I'm not sure there is anything that is producing 4k lumens in a handheld for the entire life of the battery. Even if it is only a few minutes. Most are gonna step down to keep things inside the light.
Yeah, the closest I found on SF's site was a rather large light capable of 2400 lumens for $1,370. I'll stick with my SRT9 that's only 2150 lumens but half the size and 1/10th the price.
I can't speak to the credibility of the writer, but his runtime graphs suggest the Fenix LR35R will step down from 10k to about 4k for over 30 minutes with 2x21700's. I don't know how hot the handle or the button on top of the head get during that time.
https://tacticalreviews.co.uk/?p=9482
That LR35R is interesting. Looks about the size of my old TK35, and the UI seems actually decent. 50 lumens at its lowest, though, wow. Might combine well with a keychain light.
You are not going to find anything 'compact' - which I take to mean a single-cell light with a maximum diameter of perhaps 150% cell diameter - that can sustain 4000 lumens. Far larger multi-cell lights in the 'beer can' formfactor can better achieve this, although I would still expect throttling down after a few minutes - Because Physics™; without active cooling which is difficult to implement effectively - to say nothing of seamlessly - in something that small.
It doesn't need to do 4K for the entire battery life at a stretch, just enough that it can be used reasonably, without needing to count down the seconds in my head.
