Geuzzz
Well at 4X the price it should, but… it will be fun to compare. :sunglasses:
Not the same category at all though…
Pretty much, yes. A lesser rated battery will result in less output, though it’s a bit more complex than that.
XP-G2 does not have a lower vF than XP-L HI.
Battery protection directly affects current to the point it can trip over-current protection, varies on how it was manufactured/designed.
Do protected cells even fit in these flashlights?
The FET essentially allows for direct drive, so as the cell dies the output drops. It’s not about the FET itself, it’s about the capability of the cell.
Yes, the 219C will have a lower Vf and allow for more current draw from the cell used, it will also increase heat and lower run time. The XP-L2 emitters are also low forward voltage and produce much more light out the front.
To answer Stingray’s questions…
Protected cells generally don’t fit in the Emisar lights.
FET-based drivers are essentially direct-drive, so the output on turbo depends on where the battery’s voltage sag curve meets the emitter’s Vf curve. The battery may be at 4.2V, but that value drops as amperage goes up, and it drops as remaining energy goes down. The emitter’s voltage starts at around 3V, but it rises with amps and temperature. Where the two curves meet is what happens in direct drive.
A low-amp cell sags more than a high-amp cell, so the curves will meet at a lower amount of current, and emit less light.
Lower Vf is not always a good thing. In particular, it is strongly recommended that you do not use a 219c emitter with a FET-based driver. The curves meet at such a high amperage that it kills the emitter. This can be avoided by using a very saggy low-current cell, but then it’s typically somewhat bad for the battery instead. It can also be avoided by using several 219c emitters per cell, but even then it has been known to turn emitters into smoke.
The bad-for-the-emitter vs bad-for-the-battery thing is similar to going down a mountain in a car. Riding the brakes wears out the brakes quickly, but generating resistance by putting the engine into a lower gear is hard on the engine. The brakes here are analogous to the LED, while the engine’s gearing is analogous to battery choice. The difference between battery voltage and emitter voltage is the slope of the hill. Does that make sense at all?
I haven’t tried it, but one potential option for safely running a 219c direct drive would be to use a LiFePO4 cell. Instead of going from 4.2V to 2.8V, those are more like 3.6V to 2.8V. It might work well for low-Vf emitters without having to worry about damaging the LED or battery.
I received my D1S today and used it for a hike this evening. First impressions are quite positive: tons of throw, lightweight and compact (but a large head), and the price is certainly right at $40 or less. The ano is very rough compared to the D1 and had rubbed off in a couple of spots. I like the tint of the 4000K emitter, which goes nicely with my Wizard Pro warm for night hikes. Time will tell whether it can convince me to give up the flat regulation and longer battery life of the Manker U21, which is now slated for an emitter swap for sure.
Note: when I received the light, the thermal limit was set to an internal temperature of something like 40°C, which translates to about 30°C at the head. That meant the light throttled down almost immediately on turbo and was at practically moonlight output by 10 minutes trying to maintain such a low temperature. I used the thermal config to set the limit to 71°C (~60°C at the head), which is pretty toasty but largely eliminates throttling. In the winter it will never actually get anywhere near that hot when used outside anyway. Here’s a quick plot of the head temperature at the original setting with a shift back to turbo at 10 minutes.
Interesting. The default sounds like it was too low, but that’s why it’s configurable. In my testing, the default didn’t really try to reduce the temperature at all. I think this is mostly just random variation in the MCU’s internal sensor, which isn’t calibrated. I get very different temperature readings from one attiny to the next, in identical environmental conditions.
Anyone know how to contact Neal? I haven’t received my D1s ordered November 5th, or received any notifications. My emails have gone unanswered.
Same boat, But haven’t tried emailing yet, Was going to give until end of week 
I just pasted the body of the email confirmation to a message on BLF and he shot me the tracking info within a day
I ordered the 4th and did not receive any updates until I sent him an email via reply to the original order confirmation email. He replied immediately with tracking info but that has not been updated since …………
November 12, 2017, 11:42 am
Processed Through Facility
GUANGZHOU EMS, CHINA
Your item has been processed through a facility in GUANGZHOU EMS, CHINA at 11:42 am on November 12, 2017.
Origin Post is Preparing Shipment
November 9, 2017, 6:22 pm
Acceptance
CHINA
I was going to give it at least 3 weeks before getting restless
there was an 11 day gap of tracking being updated between leaving china and getting in to NYC, but then updates resumed until it was delivered, YMMV
Well that some reassurance, 11 business days since the first and only tracking event…
I captured some beamshots of the Emisar D1S and several other lights at three locations.
I wanted to compare the D1S and D1 to help others decide which to get, or to convince D1 owners to get a D1S as well. 
I also included the Emisar D4, EagleEye X6R, and Maxtoch Shooter 2X. The D4 is obviously the floodiest of the group, and the Shooter 2X the throwiest. My X6R with a TA driver performs almost exactly like a Kronos X6.
The D1 and D1S both have XP-L HI V2 3A 5000K emitters.
The D4 is an early model with the 219C 5000K ~80 CRI emitters, not the newer 90+ CRI ones.
The X6R has an XP-L HI V3 3B emitter.
The Shooter 2X has a factory-dedomed XM-L2 U4 1A emitter.
Above, from left to right: D1, D1S, Shooter 2X, X6R, D4
In all three locations, each light is mounted at waist height with the camera positioned directly above it.
Location one is a forest trail with the lights aimed straight ahead at the tree trunk in the center.
Location two is an open field with the lights aimed straight ahead at the evergreen tree in the center.
Location three is an open field with the lights aimed upward at the tree’s leaves to accentuate hotspots and reduce spill on the ground.
The trees in each location are 115 feet (35 meters) away.
Emisar D1S vs Emisar D1:
These smaller .GIFs comparing the D1S to other lights are clickable to view larger:
Emisar D1S vs EagleEye X6R:
Emisar D1S vs Maxtoch Shooter 2X:
Emisar D1S vs Emisar D4:
The original photos’ thumbnails are clickable to view larger. Here is a link to the imgur album.
Left to right: D1S, D1, X6R, Shooter 2X, D4
Back when my D1 arrived, I posted some comparison beamshots of the Emisar D1, EagleEye X6R, and Astrolux S3 (Kronos X5) in another thread.
EDIT: Added emitter information near the top. This info was previously only included in the photos.
Amazing shots, thank you !
Now I can’t wait to have my D1S !
Great comparison shots, but you aren’t making this wait any easier!
Does the range increase correspond in poportion to the candela increase?
Nice job goshdogit………. thanks man!
For those that are waiting on an item coming from China, Customs are dragging there feet. Not sure why or why not but I have had two separate lights ordered from separate companies take about a week and half longer to get to me with no tracking information other than it is still in china until it is delivered to me. From what I can find out customs is having a hard time with this time of year.
I don’t think it’s the wait, well for me it isn’t.
I just needed to know if I had a package coming or not, or if fell through the cracks and waiting for nothing to come.
But Neal replied and i’m all good now. :+1: