Emisar D4S review


I would like to mod the Emisar D4s.
I like brighter AUX-LEDs.
The series resistor ist marked with 122, so it should be a 1200Ohm resistor.

Whats about, when I bridge the resistor.
Does the MCU limits the current for the AUX-LEDs, or does the AUX-LEDs burn imediately?
If this works, can I use this a long time or only a few seconds?

otherwise I would like to replace the SMD Resistor against a SMD-Trimmer, maybe like this one, which I already bought:


I’m unable to remove the driver from my D4, and I haven’t tried flashing on the D4S yet — so I haven’t flashed on those Emisars yet…

However, I’ve been able to successfully flash Anduril firmware on the BLF Q8.

I’m using Windows 10 (64-bit) and AVRDude works there.

Can you point out where you got AVRDude? Mine indicates AVRDude v6.0.1 <http://savannah.nongnu.org/projects/avrdude/\>

I think I installed it from a package called “MHV_AVR_Tools_20131101.exe”.

But it looks like there is an AVRDude v6.3 from the above website (which I have yet to test).

I like AVRDUDESS as its a bit more idiot proof if you want a GUI, but really you need to do some reading. You can kill your D4S if you flash it wrong and it wont be recoverable without specialty tools.

Check out the first post in this thread: Flashlight Firmware Repository

Look through the readme and read the getting started links.

Im thinking you never installed a driver for your USBASP and the links above should have the correct drivers.

I use simple batch files for flashing lights with AVRDUDESS and I have it broken up based on if im flashing fuses(potentially dangerous, only needs done once) or flashing firmware (Mostly safe)
These are both for ATtiny 85s.

cd “C:\Program Files (x86)\AVRDUDESS”
avrdude -c usbasp -p t85 -u -U flash:w:C:\Users\username\Desktop\builds.local\1.hex:a

So you would type “FW-ATtiny85.bat FWNAME”

cd “C:\Program Files (x86)\AVRDUDESS”
avrdude -c usbasp -p t85 -u -U lfuse:w:0xe2:m -U hfuse:w:0xdf:m -U efuse:w:0xff:m

Type “Set-ATtiny85Fuses.bat”

I’m hesitating about flashing anduril in my D4S, I have the hardware and I flashed the SP36 sucesfully, so the procedure won’t be difficult

Apart from the funny blinky modes, both firmwares are similar, aren’t they? I can’t find any info about the aux leds, can they still be configured with 7 clicks from off or lockout?

I Did it, only tested it one or two minutes, worked well:

Low AUX LED output is still low, nearly not visible.
High AUX LED output is much brighter than original with serial resistor.

The AUX LEDs are still adjustable, its not in the graphic but it is however in the Anduril Manual.

Anduril gets you the fun blinky modes, stepped ramp if you want it and configurable ceilings for the stepped/ramping modes.

So what that means is that the basic ramp or steps you can have max out at say max regulated 7135, and a double click goes Full turbo.

If you dont care about any of that, just let it be.

Hello, i just received my D4S SST-20 5000k, and globally i love it!

As other already said the beam is a bit greenish in the lower mod, nothing too dramatic in my opinion but i'm not a tint maniac ( no offense there ) i just like my lights around 5000k and i'm ok with 65/70 cri.

Inside, on a white wall i can noticed the greenish tint, but outside not really.

At higher output level the green is gone and the beam is whiter than my blf Q8, i like it.

I was a bit worry about the heat generation of the SST-20 5000k, on turbo the light get hot pretty quickly, that was expected, but i thought it would be way worst than that, see the video below.

Here is a crappy beam shot in lower mode, left to right : Emisar D4S SST-20 5000K > BLF Q8 XP-L HD 4750/5000K > Astrolux S1 XPL 3D 5000K > Convoy S2 XM-L 6500K

And a 3 min thermal test video with an ir thermometer and no cooling. the light was calibrated before the test at my ambient temp, 21° Celsius.

The ceiling temp was set at 60° Celsius.

i'll keep it set @60° ceiling for the moment, outside temps are around 2° Celsius so it's a nice hand warmer. But during spring/summer a ceiling @50/55° should be more reasonable.

That's my first Emisar light, and now i do understand why peoples love their products so much.

Thanks to this thread i pushed the button for the D4S and i'm glad i did it.

Only problem, now i want more Emisar flashlights. }D

the stock firmware in the D4S also has the stepped ramping and adjustable botton and ceiling for the ramp

Anyway, I just flashed anduril, I like the extra funny strobe modes

Looks like that is one of the problems. I never installed the USBasp driver. However, there appear to be some other possible problems:

  • AVRdude loaded fine for the first 20 minutes I tried it. But after that when I tried to run it a popup window appeared saying the app is not compatible with my computer. And in the cmd line prompt it said “Does not have permission.” Somehow something triggered and my computer no longer lets the AVRdude even run. I uninstalled it and haven’t tried reinstalling it yet. Maybe a reinstall will fix it, but maybe not. Or maybe I should try a different app like AVRdudess.
  • Yes, I never installed the USBasp driver. That step wasn’t mentioned in the guide I followed from earlier in the thread and I didn’t realize I needed to do that. Oops!
  • I have the USBasp and clip from amazon, but have no way of knowing if it comes wired up correctly. Hopefully so.
  • Even if it is wired up correctly I’m not sure what orientation to stick the clip onto the ATiny. Looks like 2 possible orientations: rightside-up or upside-down and I have no idea how to tell which is which. If I pick randomly and guess wrong will that permanently kill the chip or can I reverse the clip and try again?

Yes. The stock RampingIOS V3 firmware is actually a copy of Anduril with some things removed or shuffled around. The main usage modes are identical, and they only differ in terms of the extras (3+ clicks).

Is there a reason to get the XPL HI and pay the premium instead of going for the SST20 if I am going on both for the 6500k? What is the advantage (if any) on the XPL HI?

I was like you 3 weeks ago, the sst-20 5000k vs xp-l hi 5000k dilemma.

I read a lot about those 2 emitters and i finally ordered the stt-20 and i'm happy with it, under 60$ with a battery, for this awesome product is a very good deal.

In my opinion since sst-20 led are available, the 15$ upgrade for an XP-l hi is the cost for max efficiency, less heat generation, less amp draw from the cell with fet driver, and no greenish tint on low level modes.

Some peoples seem to hate the greenish tint, so that could be a deal breaker for the sst-20, but personally it doesn't bother me, only noticed it on a white wall in lower modes.

SST-20 have also a bit more throw so if it's what you are looking for, that could help you with your choice.

First Emisar light for me, and i was really impressed by the quality of this D4S, now i got a new dilemma, should i order another one with a different body color/aux led? :D

I think i will, and this time i'll try the XP-L Hi. })

I’d love to see a 21700 tube for the D4S

I can guarantee it doesnt come wired correctly. I know mine didnt.

The easiest way to orient the ATtiny is to look for the corner marking. That divot indicates Pin 1.

Also, if you have male DuPont connectors, File the end at a taper and it slips in the flashing holes on the D4S much easier.

+1. Always nice to have more options and having a 21700 tube would make the D4S a bit lighter and slightly more portable when required.

I would also prefer D4S with 21700.

I wonder if 21700 cell technology will be the one to keep growing with Tesla and vaping using it more and more. I’m glad that there are some solid 26650 choices out there but a quick and nonscientific look around leads me to believe that a bunch of new and high-performing 21700 cells have popped up recently.

You’ll get there, give it time :wink:

Yeah never say never, i agree.

For the 21700 tube that could be nice, but i do like the 26650 format, for my hand size it's almost perfect, the 18650 format feel a bit too tiny in comparison, and quad batteries like the BLF Q8 a bit too large.

But it would definitely be a nice option to have even if the D4S style would be less appealing in my opinion.

Tesla’s interest is high-density cells ala the mythical Panasonic 3.6Ah 18650 - they need range first, performance second and have the volume/mass overhead to arrange huge numbers of cells in parallel. Commercially-available 5Ah 21700s are close to the energy density of 18650s (0.74 Wh/cc vs 0.79 Wh/cc); the little information I can find on Tesla’s 21700 states 877.5 Wh/L (0.88 Wh/cc) or 21.275Wh / cell - a simple calculation to arrive at a ~5.9Ah cell … performance characteristics aren’t known but I would expect perhaps 2C.

As volume industrial customers, the power tool manufacturers can drive R&D in the high-performance cell segment - they have to build packs with low cell counts with high-rate cells and merely acceptable density and they buy in considerable volumes. This is the land of >10C cells and markedly higher $/Wh metrics.

Based on the slightly greater girth of Ryobi’s new-ish ONE+ +HP batteries and the multiples of 3AH on capacity I suspect 21700s. 3AH high-rate 18650s are probably more costly and - based on the data I can find - deliver less current than comparable 21700s. My cursory research suggests that the Samsung 30T is a likely candidate - 3AH, 35A peak current, 126 nominal peak watts per cell; as such 3/6/9Ah packs should have 630/1260/1890 watts peak power potential, respectively. Real world maximum power is apt to be closer to the 3Ah peak 630W (35A@18V), more would likely exceed the pack/tool contact/conductors’ ratings - 1260W would demand 70A, 1890W 105A.