Ouch. I really hope giorgoskok’s results aren’t the norm then. Guess I’ll find out tomorrow night when mine arrives. I don’t know how to measure that, but at that much of a difference, I’m sure eyes will tell me when sitting side by side with my U21 (that I was hoping to be able to send back if this could replace it).
2.22Amp, well, it’s even lower than some Xp-G2 flashlight
2.22*4V~9W, with 80% effective, i think the power of led is around 7W, Doubt it is over 1000 lumen
If the light is making 9w, the led will see .75amps at 12v. According to the data sheet, the led should make 880-1100 lumens. However, take into aciunt eficiency and losses that means only 600-850 lumens out the front depending on the flux bin.
Again, the Manker U21 specs were basically copy/pasted, so I'd expect what I posted in post #48, assuming they copy/pasted the light .
The 1,345 lumens I measured was at 30 secs in my NIST calibrated PVC light box (ok - PVC light boxes can't be NIST calibrated, but would be nice). I'm pretty confident my PVC light box is in the ballpark from testing 100's of lights in it. The lower modes though are quite a bit off in what I measured.
It sounds like 3 of 3 received so far are doing much lower in amps, much lower in output, so....