Emisar D4V2 Review Supplement (the pickier details)

Since you’re a collector, and own the FW3A, can you tell me if the somewhat rough beam profile with the rays protruding from the hot spot is common to compact flashlights using an optic rather than a reflector? Is that something more experienced buyers would have expected? I actually read one user review that mentioned that, but nobody else has, so I’m guessing it’s either to be expected, or most people don’t care. How is the FW3A’s beam?

The beam of my fw3a is more round then the d4v2 with regular optics . In fact it’s almost perfect circle . But this affects only your white walling activities ; corners won’t be obvious in regular usages .

It is common in triples/quads with clear, throwy optics; and to a lesser extent in lights with triple/quads using reflectors too. The FW-series has a much smoother beam because the stock optics are frosted. With clear, narrow-spot optics they will have artifacts in the beam - at close range - as well.

The D4V2 comes with a Carclo 10622 optic. It features a beautiful beam pattern, but not quite as much throw.

Carclo also has the 10621 optic which is throwier, but has an uglier beam pattern with more rings. The 10621 quad is basically the same optic shape as the popular Carclo 10507 for triples and produces a similar beam pattern. My guess is Vinh is swapping in the 10621.

I’ll be damned, always though the D4 came with the narrow-spot clear.

My (minor) gripe about the Emisar D4v2 (and D4S, etc) is the way the lanyard hole is open to the back. Tailstanding the light requires the lanyard to be pulled away from the tail in a two-handed operation, otherwise the light will invariably sit on the cord and be unstable. A lanyard hole accessible from the side, like on this Skilhunt, is a better solution.

Good pont. The side-positioned lanyard opening probably would make tailstanding a bit easier. I tailstand the flashlight frequently and I noticed the same issue a few times. Usually I can deal with it one-handed by holding the flashlight with my first few fingers and using my pinky to sweep the lanyard out to the side as I set the flashlight down. But it occasionally gives me trouble.

But, yeah, not at all a problem. Maybe just something for Hank to consider for future flashlights.

I made corrections in the battery and runtime sections. It turns out that my flashlight’s thermometer was not calibrated but was 8° low. I had checked it before, but maybe that was before updating the firmware. I did not perform a factory reset after the update as recommended. Either the update screwed up the calibration, or something happened to it since then.

Anyway, Turbo now steps down much more quickly, and the flashlight does not get as hot. That also means Stepped Level 6 ramps down eventually, even with my hand bleeding off heat. It needs a higher temp limit to run indefinitely. I effectively had my temp limit set to 53° before due to the incorrect thermometer calibration. Level 6 got pretty hot when I performed the rundown test, but not too hot to hold. Now the flashlight gets only moderately hot with the 45° limit. Not at all uncomfortable.

Don’t forget to check your flashlight’s thermometer!

Flashing the firmware erases the EEPROM by default so your calibration will be lost.

Great write up! always good to see another fellow D4V2 geeking out about the specs :smiley:
I face high parasitic drain on my D4V2 on low aux mode, even on aux off mode.

I measure my cells everyday with a multimeter and seem to be losing .1v everyday which is way too much.
During the period of testing the lights were not switched on to use at all.

Could more people do some testing of their D4V2’s parasitic drain? I have flashed to the 2020/03 latest firmware and it doesn’t resolve this issue for me :frowning:

Thanks!

TK’s review quotes the parasitic drain as the following:

Parasitic drain:

  • ~0.02 mA with aux LEDs off (17 years to drain a 3000mAh cell)
  • ~0.06 to ~0.12 mA with aux LEDs on low mode (2.5 to 6 years)
  • TBD mA with aux LEDs on high mode (my sample has different resistors, so I can’t measure)
    (probably about ~0.2 to ~0.4 mA on blinky mode, or 1 to 2 years runtime)
    (probably about ~3 mA on high mode, or about 50 days runtime)

1Lumen’s review also gives amp readings for the aux lights. With the aux lights off, his parasitic drain reading is 25μA (0.025mA). Only slightly higher than TK’s reading. At that rate a 3000mAh cell would last 13.7 years. On low they range from 70μA - 190μA. Again, just a bit higher than TK’s readings.

So there’s obviously a problem in your case. I have had mine on one aux mode or another since I got it. Recently I had it on voltage mode, low, for a couple weeks or so and I even used the flashlight for brief times and the voltage did not drop much at all during that time according to the Batt Check mode. I’m even using laptop cells with only about 2,000mAh. I do not have any way besides the flashlight’s Batt Check mode to check my batteries’ voltage, though.

I think either your flashlight or your battery must be defective. Can you get a tailcap amp reading with your multimeter to see how much current is actually being drawn? Also, are you sure your battery is in good shape? If it is worn out or a cheap Chinese knockoff, it might no longer be able to hold much charge.

I love my 4000K SST-20 gold jobbie and I’ve never bothered to fix the ‘muggle’ mode issue, since I don’t currently possess any.

Maybe one day, when I buy one off of Ebay, I’ll reconsider?

Chris

Yes I did a tailcap measurement with my multimeter and on low aux the drain I’m getting is around 18ma which is way higher than expected.

I suspected my batteries might be the issue and have purchased a new pair of Sony VTC6’s but the issue is due to the high parasitic drain.

What do you mean with “not model specific”? How did you compile it?

Disregard what I typed, I got confused with this .
I don’t really have an idea what how to navigate the site and assumed it contains all the version hex files. Got confused with the changes revision part of the website.

I have this current version installed.

Sorry I got confused

You linked the D4Sv2 version, not the D4v2 one. While it should work, it has different ramping tables. But your high parasitic drain is not related to that firmware. It sounds more like a hardware fault.

I did a search on reddit and I am not the only one facing this issue, I just hope for more users facing the issues to post more details so we might figure out a fix.
I understand why you’d guess its a hardware issue but could any Electrical engineers chime in what causes it?

Every function of my light is working as expected so it’s hard to send it back and claim its faulty.

Just how low were your cells getting? Dropping to ~4V fairly quickly from 4.2V will happen to an li-ion cell without even being in a light.

yeah I understand how fast they drop voltages from 4.2, I did measurements on the cells everyday and on average am losing 0.1v every day till they hit 3.4v and I took the batteries out
so that was roughly a week of standby in low aux mode.

Thank you for the detailed review. I look forward to get the D4V2 in Nichia 219C with frosted 10623 frosted optic, SS bezel and 18350 tube.