TK's Emisar D4 review

They do have their place, mainly to free up both hands when working etc. Disadvantages come when others are around(dazzle people nearby).

DELETED due to lack of anyone reading, understanding or actually giving a rip

Can’t get D4 out of my head. :slight_smile:
This light really shows how UIs of my other flashlights suck.
Very rich, but not complex. Allows to do nearly anything that I want quickly. Doesn’t really have a lot to memorize. Click, click+hold, 2-click, 3-click, unscrew slightly. Not little, but far from the 20-clicks I’ve seen in a similarly rich driver.

Nevertheless I have some thoughts, which may or may not be an improvement.
I just got stuck in the momentary mode. How many times do I need to click to escape it? I needed to look up a diagram. If screwing / unscrewing the tail would reset that, it would be nicer (though I recognise some may want to keep this mode forever, regardless of battery changes).
It would be nice to have a shortcut to roughly-max-thermally-stable mode.
If I enter thermal calibration mode, press and hold until it starts showing the current mode, then start clicking, the light behaves funny. Click turns it on, but at the next digit it turns off by itself and continues showing the number. I guess it would be better if de-pressing the button made the light quit the thermal-calibration mode immediately.

Have been playing with the ramping for a few days, I felt the need for an extra way to get to a maximum sustainable mode directly (so not after letting the, well working, thermal stepdown algorithm figure it out). I’m sure in most situations that is about 2.5 A in this light.

Been thinking of ways to implement this.

There is the short hickup at 350mA, easiest is create a same hickup at 2.5A but once you see it you overshoot it, it is not precise.

A way to implement is to let ramping up stop at the two locations. Letting the switch go and pressing it again resumes the ramping to the next stop.
This requires the ramping-down to have a new unique command, that could be the shortclick-hold that DrJones uses in his ramping UI.

TK and Tom and Led4power and the Dr have been tinkering much longer about these things so I realise that my thoughts may be primitive and flawed, but I wanted to post it anyway :slight_smile:

Coincidentally, Agro just posted the same need for a direct access to the maximum thermally stable mode. :slight_smile:

With a Lamp on your side you can get distracting light distribution if you use it at armlength.

In fog or rain left and right eye see different brightness. Thiss can be annoying

Your neck musculature isn’t trained for sideload. Waering a light sideways a few hours you will fell it the next day.
Front mounted is easier.
A LED in front, battery on the back of your head is even better.

For working in narrow spaces you dang your head often sideways seldom the front. You are usually better avoiding a slam in your face.

For a dedicated headlamp you want a broad beam over 100 degree if need it for armlength to 3 meter distance. Side mounted you have a shadow.

What is this clip ?

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.

  1. I would skip the max thermal step if it’s dimmer or equal to the old brightness.
  2. 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.