TK's Emisar D4V2 review

The problem is that will be MUCH more expensive and time consuming for Hank, that’s a huge increase in different models you need to build and stock if all emitters are offered for both models… even worse if you have more than one body color, optional alternate UI, etc. for both models.

He already has the option of saving money by allowing the light to be bought without the pocket clip, with aluminum bezel instead of SS and using cheaper emitters than the XPL HI.

What’s wrong with 18th-century English furniture fashion? Got a thing against rococo ornamentation?

Ish.

If the temperature is changing very slowly, it doesn’t respond until it passes the threshold. But if temperature is changing quickly, it reacts before it hits that point. So it may actually start stepping down at like 35 C, in an attempt to avoid overshooting the target temperature. Similarly, if it’s at 60 C but the temperature is dropping quickly, it may actually increase the output. It tries to predict where it will be in the near future, and make adjustments based on that.

It doesn’t always adjust quite how it should though. Sometimes it still overshoots or undershoots, particularly on the D4. Lights with a lower power-to-mass ratio tend to behave better. And lights with a FET+N+1 design tend to behave better than FET-only or FET+1 lights. The extra mid-ramp resolution seems to help the regulation algorithm.

It would probably think it’s overheating most of the time, especially when hand-held since humans are hotter than 31 C. And then it would stick to the lowest level allowed by the regulation algorithm. On the D4, that’s at the 1x7135 level, or about 130 lumens.

However, turbo would still last for a few seconds. It has a minimum time period before any adjustments are allowed, to make sure the higher levels can always be used as a burst mode. Basically, the thermal warning events are rate-limited to make sure they won’t fire off nonstop. This also guarantees at least a few seconds worth of turbo, even if the light is very hot.

IIRC, Zebralights are set to ramp down at 55C, though that’s adjustable +/- 5C. I’m not sure if they really get that hot, because they don’t feel that bad to me. Yes, they’re getting uncomfortable, but are still very holdable.

I just narrowly avoided snorting hot coffee out of my nose.

—Bob Q

TK, as you know I’ve been away for a while. I did order this new D4 V2 when I learned it was for sale and I forgot about the implementation to safeguard the LEDs when using the Nichia 219. A friend advised me to change my order but that wasn’t possible. Is it still true that total output is limited via firmware for this emitter? Probably obvious that I didn’t buy this for absolute power but favoring the rainbow aux display… the light will probably still get hot even given the limitations, right?

Hard to keep up anymore, too much going on outside the realm of lights. Sorry to be asking such elementary questions…

I think the sensor in them might actually hit that temp but that single-piece body pulls the heat away so fast the head doesn’t have concentrated heat like on many other lights. If you leave a ZL on the highest mode without any fan or your hand to cool it the whole body heats up to that temp for sure but it takes a while.

Assuming they are using the 80% firmware for the 219C version:

It will absolutely get hot fast still because that’s still a ton of wattage for such a small light, and the 219C 90CRI are less efficient than other options like the XPL HI so they will produce more heat.

The loss in perceived brightness from the throttled firmware version isn’t really that much though.

I’m English, and I feel like I have missed a joke I should have understood…

You missed a joke about furniture from the 1700s, shame on you.

If you don’t want a light with aux LEDs and all the bells and whistles of the Anduril firmware, then I think you’re in the wrong thread! It’s an enthusiast light from a manufacturer who aims their products at folks who love to tinker and are happy to accept fun yet-superfluous features. If you want a solidly-made light with a simple UI and minimal extraneous functionality, buy a Fenix or Olight.

I’m also confused at how you can hate Anduril yet be happy with NarsilM - they’re very similar!

FWIW, I will most likely replace the Nichia 219’s with Samsung LH351D in U6 5000K 80 CRI variant and re-flash the MCU as needed. Sure wouldn’t be the first time, but would be the first for the particular MCU used. :wink: Will probably have to call on my friends here for some help, most likely already expected. lol Nearly a thousand builds behind me and somehow I feel like I’m starting over… again…

well that didnt last long….

Everything was working fine last might, came home form work today to find the button had popped off, put the button back on ( although it wont seat correctly) battery in, and nothing - dead.

a few problems:

Ouch, I would speculate that something over-heated, which explains (1) why it's dead and (2) heat caused air pressure to increase, behind the button, causing it to pop off.

You've changed the battery?

An user at the German flashlight forum (TLF) had a similar problem: Emisar / Noctigon Laber- und Bestellthread | Taschenlampen Forum

The flashlight turned on by itself and burned a hole in the holster. The button popped of too. Maybe your d4v2 turned on by itself too?

the battery was only changed as it wouldnt work, when carrying it ive developed a habbit of switching it off ( twsit to tailcap) to prevent pocket activation .
ther report on the German forum is worrying, as i was hoping to be able to leave it powered up with the AUX LEDs on so it could be easily found in a tent, where it was located when found was a relativly safe place, however if it was in a tent/near combustible material the outcome could have been very different, looks like the same thing has happened to me :frowning:
The question is whats the resolution to this problem??
while i was asking about the thermal regulation previously, nothing has been changed from the original as sent out settings ( didnt want to mess it up until i was 100% confident)

Google translate shows this

Ouch Pint!

That doesn’t look good. I agree that it looks like something overheated. Overheating can explain what is visible in the photos you provided:

  • Button boot popped off - If the light overheated, air pressure inside the light might increase, putting pressure on the button boot making it more likely to pop off. Also, the button boot retaining ring is steel and is held in with a friction fit. If the aluminum head heats up at a faster rate it may expand, possibly enough to cause the boot to loose friction and come off.
  • Positive wire from the driver to the star popped off - If the star gets too hot it might melt the solder at the driver wire. When this happens the wire can pop off, causing your light to become non-functional.

Neither of these things should have happened, but fortunately both should be fixable if you have a soldering iron and maybe some super-glue. You can try contacting Hank and returning it for repair, or you can try fixing it yourself. If this happened to me, I’d try the following:

  • Check bottom of the driver board inside the head to see if there are any shorts in the battery compartment. Did the spring at the head come off?
  • Desolder and remove the aux led board. Before doing this, take detailed photos showing which aux led wire goes where so you can reassemble it. You will need fine-tip soldering iron tips for the aux board and a wider tip for the star.
  • Desolder and remove the negative wire on the star.
    • Lift off the star* and check the solder paste under the star. A driver wire to a star desoldering itself is often a sign of insufficient thermal paste underneath. If thermal paste is insufficient, heat can’t get out of the star fast enough causing the star to overheat. In extreme situations this can cause the star to heat up enough to melt the solder on the star. Spring tension then often causes a driver wire to pull out of position. Best to double-check and replace with new thermal paste if needed.
  • Reassemble, this time soldering on both positive and negative wires to the star, plus aux LED wires.
  • For the switch boot, I would try pressing the boot back in place with the stock retaining ring. Make sure it is fully seated and take note of how much pressure is required to seat it fully. If a lot of pressure is needed I’d skip glue. If it seems loose or pops out again, I’d put glue underneath (probably Fiberfix optical super glue).
  • Calibrate the temp sensor in the UI and the thermal rampdown. Even if it turns on in the pocket it really shouldn’t get hot enough to actually damage the light. Thermal rampdown should have protected it from damage.
  • Test the light. Put it in turbo tailstanding on a fresh cell and leave the light on. If everything works perfectly, the light should ramp down without suffering any damage.

The positive wire is unsoldered. A defective solder?

Im OK with soldering some things, de soldering and re-soldering the aux board is a task for which i lack the correct tools, i could re-heat the positeve lead and dab it down, and press the switch in again, however the report over on the German forum shows the same thing happening, almost as if it switched on by itself and got warm

It could have been a poor solder job.

Except that Pint also reported the button boot came off, which suggests overheating.

I never heard of any Emisar problems when it’s using ramping firmware , maybe it’s just a coincidence that problems are popping up now they are running on anduril :question: