I have troubles to calibrate it thermally. It’s always too hot.
If I start with a cool light, delay makes it overshoot. Now I did a hot-start.
Previously I got it at 36 or so. I warmed it up slightly, waited to cool down, so it was well within my comfortable range, started heating up, stopped almost immediately. Result? 71, way above what I can touch.
now:
random brightness 2 clicks> Turbo -> 2 clicks -> old brightness
What about adding the thermal save level like this :
random brightness 2 clicks> Turbo -> 2 clicks -> max. thermal save brightness 2 clicks> old brightness
TK, are the sources of the thermal control simulator that you wrote available somewhere? I’d like to play with it.
On another topic, I went to the kitchen a moment ago and took a mug. I noticed it was dirty, it had something yellow at the bottom. I moved it slightly to see it better and the yellow thing moved. Afterimage again….
Yes, the clip is great quality & it fits D4 perfectly well. The only place I know sell this clip is from Taobao
Very nice. Wish I could translate it to English. Hahahaha
Maybe just pause for a moment and then continue, as long as the key is pressed? I’m afraid that otherwise users would be stuck at 350 mA thinking it was the max……showing off how they have light that’s brighter than the neighbour’s.
Interesting. Once user has used turbo, their night vision is destroyed already, so putting another bright mode in the middle shouldn’t hurt really.
Though I would consider implementing this idea slightly differently.
- I would skip the max thermal step if it’s dimmer or equal to the old brightness.
- Actually I would skip it too if it’s only slightly brighter than the user-set mode.
Pros: no useless transitions.
Cons: User may be unsure whether the next 2-click will go up or down in case they had level somewhat close to the limit. This can be made less of a problem by making the required difference to be quite large, so the “hey, my mode must have been lower” reaction is nearly guaranteed.
My personal solution was to make it accessible with a 3-click, shifting other modes.
I don’t know which of the 3 ideas I would prefer.
Thank you.
Anyone know if the BLF A6 clip will fit the D4?
I would keep the battery check at 3 clicks. That is consistent with other lights.
And I can easily remember it. B attery = 3 clicks
I think it’s a cleaner way to have two stops in the ramp. It’s simpler and less to remember.
Not sure, but TK put a link in her review for a Convoy clip that fits toward the end of her review.
Five clicks for a strobe similar to the one in BLF A6 would be great.
Perhaps in V3.
I have that clip. It’s a bit too long for my taste. Also it’s scratched off the anodization on both my 18650 and 18500 tubes, so i’m not too thrilled about it right now.
Would knowing actual LED temperature help thermal management?
I ask because I just learned that you can calculate it from Vf. It would require different firmwares for different lights though.
Best solution is probably a firmware update.
Change the UI as follows:
- 3-clicks - shortcut to 2.5 amps … This is similar to what DrJones did with his lumodrv ramping firmware. Triple-click is easy to access and is helpful to use as a shortcut to another well-used mode. Another option is maybe set this at 3 amps. It might still ramp down at 3 amps but probably not for a few minutes and probably not by much.
- 4-clicks - shortcut to battery tester
- 5-clicks - shortcut to tactical momentary
Everything else can stay the same.
Link does not work…
Does anyone have an estimate as to how long each led can run on turbo before it’s thermally regulated? Or a discharge curve as to the amount of total runtime on its highest setting? I want to choose a flashlight that is amazingly bright but also practical. If it can only sustain turbo for a couple of seconds, then it’s not the light for me. Thanks for your input.
Depends on cell and ambient temperature, but for the 219C it’s 15-20 seconds (from cold) on turbo (before it starts to step down).
The D4 can only sustain turbo for a couple of seconds, it varies with the emitter choice but very short it will be! Amazingly bright in this size will just get amazingly hot, whichever flashlight you choose, and the D4’s well-working thermo-regulatation is as practical as such a light gets.
There’s more settings than just turbo though, still pretty bright and also sustainable, actually for the size the D4 is build very well thermally (i.e. better than an S2+)
You may want a bigger light though, much more heat capacity and heat-shedding surface area.
Forgive my ignorance, as I am not fully comprehending the output graphs posted in the OP, but what is the max sustained lumen output of this light? Am I reading it correctly that it’s only about 150-200 lumen? This can’t be…
In turbo, it seems to be dropping like a lead balloon immediately upon engaging, which, if it’s really about 4000 lumen, that’s understandable, but at what lumen level does it level off?
Like other lights of comparable size (think S2+) D4 can sustain about 1000 lumen without breaking, but it will be way too hot to touch then. I can confirm CRX’s test that between 500 and 600 lumen and hand-cooled it is sustainable. When outside with airflow all flashlights can run brighter without overheating.
Charles Lin, Efest makes a dark purple 18500 1000mAh cell that’s high discharge… it gives me some 3400 lumens on my scratch built Ti/Cu Quad and 3200 lumens in my Mec-Army P16 Quad.
