As stated, it’s an estimate. The actual output is complicated, but the estimate gives people a rough idea of what to expect.
Of course smooth ramping is very usefull for flashlight which cant work longer than 30sec from start .
You might have a point if the light only had “off” and “direct drive 100%” modes. Fortunately, there are 149 other levels in-between to cover a wide variety of situations. Unfortunately, exaggeration and polarization are almost never helpful, so I hope that can stop.
And no steps is great achievent when any level will loose several % of output every minute :person_facepalming: .
Levels 1 to ~64 are current-regulated with long runtimes, and are quite useful on a small light. Above that, the levels are partially regulated and partially direct-drive. The runtime graphs should look similar to the BLF A6, where high modes sagged over time, medium modes sagged but only a little, and the entire bottom half of the modes were very close to flat.
This method gives low and medium modes which are pretty stable and practical, while also giving good “wow” modes. So it can be practical or fun depending on what you want at the time. Is it a problem to have some fun modes?
Reviewers didn’t generally measure the lower half of the modes, because the runtime was too long, but the graphs for those are mostly just a flat horizontal line.
On a FET+N+1 driver, the regulated portion goes much higher, like 3A instead of 0.35A. So it can be regulated up to about 1000 lumens instead of just ~150. This doesn’t matter much to me because I normally use less than 150 lumens, but it’s nice to have sometimes.
Just imagine that youve bought car, and seller claimed that it can go 100mph. But after some time you realize that this can be only reached with 95-100% tank load, with 50% tank load it cant go faster than 70mph. And there is no document which will show this feature, no method to calculate actual values.
You mean, like how the M43 can run at 100% without losing any output over time? Let’s find a runtime graph… (red line)
Maybe car analogies aren’t very relevant here.
The M43 does a pretty good job with power and thermal regulation (though the thermal regulation is a bit bumpy). However, virtually every flashlight sags quite a bit when running at 100%. And that’s okay. Some manage to get a flat graph on medium modes, which is nice. Others still sag a bit over time, which is not as good but usually not noticeable by eye. And both the M43 and D4 have regulation on low modes.
They are both good lights. I don’t understand why a few vocal people are upset about the D4. I expect I’ll enjoy mine quite a bit.