Emisar / Anduril - stepped low mode “jump”

LED Flashlights – General Info 18650 Flashlights
1

I am sure this has come up in the numerous threads about Anduril and it’s functions, but I don’t know if what Im Experiencing is UI or the driver(s).

Here it is:

When I set my d4v2, d4sv2, kr4 to stepped ramping the same thing happens where the first step and second step have a huge gap between them. It doesn’t matter if I set the steps to 5 steps or 10, it happens. The first step is an awesome low moonlight IMO, but the Second step is always a pretty decent jump higher. In ramping I can find a light amount in between, but in stepped mode there is no way to get something between ultra low and the “too bright” second step. I have set my stepped mode light parameters to low @ 1/150 as well.

I actually have come to like the stepped ramping more as I find it more functional for me.

Am I missing something? Is there a way to adjust that second step? Is this a driver thing or an anduril thing?

2

There’s not enough resolution of the driver at the low side and the ramp shape is a compromise between “many repeated steps” and “linear appearance”.

3

Thank you. I figured it was something I wouldn’t understand even if explained to me. I appreciate the info. Judging by how my knowledge level has been scaling since getting into this hobby, I will understand what you wrote in about 6 months :sunglasses:

4

Picture a straight line, starting point would be moon end would be high. now divide the line equally by number of steps. basically the way it works

5

Just that the start is something like 1, 1, 1, 2, 2, 2, 3, 3, 4, 4, 5, 5, 6, 7… and the end like 800, 900, 1023. So at the beginning we have not enough resolution to get a smooth transition and repeat some levels so that the ramping is not tooffast. At the end we skip many steps because the change in perceived brightness is small.

6

Yeah, er, basically the hardware has rather coarse steps at the bottom end… and the firmware tries to compensate for that but there’s only so much it can do.

Basically, if we convert the hardware resolution into how it looks by eye, the ramp looks something like this:

This is more visible on the KR4 than on the D4, since the KR4’s lowest power channel has 4.8 mA per step (5A / 1024), while the D4’s lowest power channel has 1.3 mA per step (0.35A / 256).

I sent Hank some ideas for how to improve it. It would require adding a third power channel though, which is difficult on a tiny circuit board… and he’s pretty busy. So I don’t know if it’ll ever happen. But maybe someday we’ll get something like this:

Top left: D4 driver
Top middle: KR4 driver
Top right + bottom middle: proposed KR4 driver with an extra 20mA / 256 power channel for 0.08 mA steps

7

Wow, thank you! @ SammysHP and jp9mm - i appreciate the breakdown of more easy to understand verbiage! TK - thank you for the breakdown! the explanation about the lower power channels makes sense to me, as i have been reading a little recently about how that all works. the diagrams definitely put it into perspective. I know this isn’t enough to even complain about given everything these lights offer (especially for the price), but i just wanted to throw the question out there in case there was an easy work around. I figured it had something do with power and was not as simple as an adjustment to the firmware. Appreciate the info, all!