[REVIEW] Emisar DT8 - Osram W2 & Nichia 219b SW35

Video Review of the Emisar DT8. This is an awesome little hotrod that provides a crazy output in a package barely larger than the D4V2. It is definitely aimed at enthusiasts, and is not very practical overall. I love using these lights, and I think they’re an awesome addition to a collection, but I can’t recommend them to most users looking for a practical light.

UPDATE: The DT8 has been superseded by the DT8K, which runs off a 21700 cell instead of an 18650. I recommend this over the original version I reviewed here.


This review covers the DT8 in two variants, one with Osram KW CSLPM1.TG emitters, and and the other with Nichia 219b SW35.

Please note: In the video above, the “W2” were incorrectly labelled as CULPM1.TG, when they are in fact the S version. Both LEDs produce the same beam, as they have identical dies - the difference is the thermal pad.


Summary:

What I like:

  • Crazy high output
  • Compact with a great comfortable-to-hold form factor
  • Great build quality
  • Emitter choices
  • Anduril 2
  • AUX LEDS!
  • 219b light has a fantastic beam

What I don’t like:

  • HEAT - this thing gets crazy hot! (Unavoidable, but an issue nonetheless)
  • Beam quality on the W2 model isn’t great
  • Not really great for pocket carry
  • I still think a 21700 version would be better, with more reasonable runtimes

I tested this light with the Molicel P26A, Samsung 30Q, and Keeppower 10A 18350. The 219b model is using the KR4-219b.hex, which provides 11% lower output on Turbo than the KR4-219.hex firmware which came loaded onto the light when I got it (60% vs 50% FET). This is not really a visible difference, and less heat is produced. Thermal limit was the default 45C.
The W2 light’s thermal limit was set to 55C. I am not guaranteeing that my measurements are super accurate, but they should give a good idea of the performance between these two.


The W2 model with the P26A produced 8,600 lumens on Turbo @ startup, the 30Q 7,800 Lumens, the KP 18350 5,700. This is an incredible amount of light, and is extremely impressive for such a small flashlight!

The 219b is much less bright, with both the P26A and the 30Q producing 3,200 lumens @ startup. The KP produced 2,300 lumens. Not as impressive, but this is still a ton of light, and more importantly all of it is a beautiful warm color with high-CRI and awesome tint.

Of course, these lights get extremely hot very quickly, and Turbo drops very fast. After step-down, the output on the W2 will vary between 500-750 lumens, while the 219b will produce 190-275 lumens. This is pretty good for sustained output from a single 18650, but honestly I hoped for a bit more.

High will produce 2,100 lumens on the W2 and 1,900 on the 219b, with the stable level on both being the same as Turbo after step-down.


Here’s a ton of graphs for your enjoyment:

Emisar DT8 Review Measurements - Osram W2 vs Nichia 219b


W2 vs 219b Turbo Total Runtime (P26A, full output)

https://i.imgur.com/4lT4P0U.png


The first turbo graph is not very flattering - changing our y-axis to 1,000 lumens gives us a much better view of what’s happening, which is actually pretty good:

W2 vs 219b Turbo Total Runtime (P26A, Max 1,000 Lumens)

W2 vs 219b Turbo Total Runtime (KP10A, full output)

W2 vs 219b Turbo Total Runtime (KP10A, Max 1,000 Lumens)

W2 vs 219b Turbo First 90 Seconds (P26A)

W2 vs 219b High First 90 Seconds (P26A)

W2 vs 219b High First 30 Minutes (P26A)


The difference in thermal drop between High & Turbo - note that they’re very close in % drop, despite the Turbo being quite a bit hotter. This is due to the heat being produced by the LEDs rather than the components on Turbo

W2 High vs Turbo % Relative Output Thermal Drop (P26A)

W2 High vs Turbo Lumens Thermal Drop (P26A)


Bumping thermal limit up to 55C from the default 45C gives a decent boost in Turbo performance - all W2 graphs were done at this setting. However it gets very hot in the hand, and I would not push it harder than this:

W2 45C vs 55C First 120 Seconds (P26A)


Finally, momentary turbo disables all temperature regulation, so what we are seeing here is the battery+LEDs running uninhibited. This generates extreme heat and is **VERY DANGEROUS**, so don’t replicate this test

W2 Momentary Turbo Lumens (P26A)

Standby drain on the Aux lights is basically the same as the D4V2. Because the High levels are really high, they will drain a lower-capacity cell like the P26A pretty fast, so I have mine set to automatically lockout after 30 mins (with low AUX) to save battery and provide some extra safety.

Low:

  • Red:0.09 mA
  • Yellow: 0.1 mA
  • Green: 0.07 mA
  • Cyan: 0.09 mA
  • Blue: 0.06 mA
  • Magenta: 0.1 mA
  • White: 0.12 mA

High:

  • Red: 3.58 mA
  • Yellow: 4.08 mA
  • Green: 0.81 mA
  • Cyan: 1.22 mA
  • Blue: 0.7 mA
  • Magenta: 3.97 mA
  • White: 4.47 mA

Off: 0.04mA with regular jumps to 0.26 mA

Ultralow has been dramatically improved with ToyKeeper’s latest updates to Anduril on these drivers. On 1/150, I measured 1.8 mA on the W2 and 2.08 mA on the 219b. Both were so dim that I couldn’t properly measure the output, all I can say is that they are no brighter than 0.07 lumens.


Beam quality on the 219b model is excellent, with a lovely warm (3500K) rosy tint, and the floodier beam is clean and very useful for most illumination tasks indoors and out, though there isn’t much throw - I measured 4.3 cd/lumen, for a maximum of 14,262 cd.


The W2 has a much less pleasant beam, being cool white and low CRI. There is a noticeable greenish tint in the outer edge of the hotspot, and the spill is full of rings and artifacts. The hotspot is tight and throwy, providing 9.9 cd/lumen with a max of 89,130 cd. I do not like this beam, but honestly I’m willing to accept it for the incredible amount of light that comes out of here. For practicality and real usage though, the 219b is easily superior.


Overall, I really enjoy using these lights. While I do still think a 21700 version would be better, I understand why Hank opted for this form factor. For all intents and purposes, this is basically the D4V2 EXTREME EDITION, and I have come to really appreciate this design - I want more rectangular flashlights now! However, this is not the kind of light I feel comfortable recommending to most people unless they really know what they’re getting into. If you are an enthusiast, the DT8 is an awesome little light to add to your collection.


These lights were both sent to me by Jackson Lee for the purposes of review. The video description does have 5% discount codes for his webstore jlhawaii808.com and his eBay store. I was not otherwise paid for this review, the discount codes don’t give me anything. All opinions here are my own.

Also, this is the second time I wrote this review, the first time as I tried to post the site went down for maintenence and I lost everything I wrote (my bad):person_facepalming:

Anyways thanks for reading/watching!

2 Thanks

Ooops! My sincere apologies! (Normally it should stay in the browser cache if you hit the back button.)

Really glad to have you (and your reviews) on BLF. Well done! Looking forward to the next ones.

1 Thank

Fantastic review!!! :person_with_crown:

Awesome review!

That's the kind (of quality) we need here!!

Haha it’s okay, funnily enough I had this gut feeling that I should save my review as a doc first before posting it here… but I didn’t do that.

Thanks for the welcome! I’ve been lurking here for a while, but only just started posting. This is a great place, one of the best communities online :slight_smile:

Thanks!! I’m really glad you guys enjoy the reviews! :smiley:

Please enjoy your time here, LuxWad!

Haha thanks, so far I have
…I wish there was a decent laughing emoji though

1 Thank

What took you so long to get here, LuxWad? :wink:

Man… your video review looks amazingly professional. Super job. Is your day job in the videography or photography domains?

I’ve still put off getting a DT8 for the main reason you stated — lack of 21700 support. Frankly, this light is in a weird zone—too big to EDC in a pocket, but too small to adequately manage the generated LED heat.

I’d really like to see Hank come out with a DT8S, “S” for “Super.” A little larger head with more aggressive fins, improved thermal pathway, and 21700 cell support.

Btw, friendly tip on writing content on any forum: once you get a decent amount of content written in the editor, do a select all and copy. Get that stuff in the paste buffer. Or you can keep a lightweight text app running on the side to dump versions as you go. I’ve saved myself a lot of headaches this way.

Haha, I took a while because I’m actually a bit nervous about sharing things online, BLF seemed a bit scary for a while. I’m glad I started posting here though!

I’ve been producing video content for a long time, only in the past couple years have I been doing it professionally. Nothing crazy, I’m still relatively new to it. I aspire to be a film director someday, and my education & work is striving towards that. I prefer not to give too many personal details though :slight_smile:

I like flashlights of course, but these videos serve a very important auxiliary role for me: they provide extra filming/editing practice, and help me to experiment with new and fun video production techniques. I get to improve my filmmaking and review flashlights, so it works out very well.

I think this would be ideal, the DT8 is a great little 18650 light but the small hotrods aren’t really my thing, I prefer bigger lights which can sustain their output and provide long runtimes.

I’ll have to start doing this now :laughing:

Has anyone tried the regular KR4.hex with the 219b LEDs? I’ve heard some people saying that if you just use a 10 amp 18650 there’s no real worry of burning the LEDs but you’ll get quite a bit more output than with 50% or 60% fet. If anyone’s tried it I’m really curious I have the $3,500k 219 B’s in my D4 V2 and although it’s fairly bright it’d be nice to have a bit more output

Post has been updated, with added with inline graphs and beamshots.
Also added a correction, the video stated the W2 light was using CULPM1.TG LEDs, when in fact it has CSLPM1.TG emitters.

That shouldn’t burn out the LEDs, but it will get quite a bit hotter without a massive increase in output. I wouldn’t recommend it.

1 Thank

Thanks for the review!

Edit: I did not realize this was too different lights, I thought it was a channel switching one.

The max output I measured for the 219b light was 3200 lumens (3580 with the 60% FET control), which will provide that extra throw you’re missing.

It should be much higher, given that the output of the DT8 is significantly higher than the D4V2 - For reference, my W2 D4SV2 (which will provide the same output) will put out 5,000 lumens with the Molicel P26A.

The DT8 uses a Carclo 10611 rather than the 10622, which is throwier and should perform about the same as the 10621

My bad, I didn’t read carefully and thought this was a single channel switching light.

[quote=LuxWad]

Still scary to me hehe :-)

Thank you for the excellent review, I just received mine today. Amazing little powerhouse of a light.

Yes it does get hot quickly and Turbo does not have a long life expectancy but, I rarely leave
my lights on Turbo for long periods of time. Just long enough to see if there are
any rattlers, javelina, bobcats or curious coyotes ahead when I take my nighttime walks.
This light fits perfectly in my hand or pocket and, there is no uncertainty knowing where
the power switch is like there is on some of these lights.

Fit and finish are perfect, I can’t find one single flaw on it. Do I wish it was powered
by a 21700, of course, but I have zero regrets on this purchase. It’s a great companion
to my D4S.

Great job Hank.

regards
Andreas

2 Thanks

I’m getting a “New DT8 with tint ramping and channel switching” from Hank. Any suggestions on the LED config for the 2 channels? I’m a bit baffled… :frowning: