Emisar D1S VS Nitecore P30

LED Flashlights – General Info 18650 Flashlights
1

Hello

Anyone has the two lights for comparison ? I would like to buy the D1S and i saw the P30 today…

The two looks good

D1S Dimensions:

18650 length: 127.5 mm
Bezel diameter: 50.0 mm
Pill diameter: 36.0 mm
Body diameter: 23.9 mm

P30
Size: 141.5mm x 50mm x 25.4mm(length x head x body diameter)

2

D1S:

  • cheaper
  • stronger
  • little smaller
  • probably much better UI (dunno)

P30:

  • longer runtime (read: more efficient)

For me it’s clear.

Though you can get UTorch UT02 / Manker U21 for about the same price….

UT02/D21:

  • larger (but not much)
  • heavier (but not much)
  • very similar performance to D1S
  • should have even better efficiency than P30
  • supports 26650 batteries for c.a. 50% better battery capacity
  • much worse UI than D1S

It is definitely not a clear winner over D1S. In fact I think D1S is usually a better option. But it’s worth considering.

3

How much throw does the D1S have in 3A 5000k tint? I just bought it but have no idea.

4

Best would be an UT02 with TA triple channel driver and Narsil FW…
But yeah, I think I’m gonna like the D1S anyway.
Sorry, Mizou, I don’t own the P30… maybe Nitecore could send me one for review to compare :-p

EDIT : the UT02 has an XHP35, and so is not usable with TA driver sorry…

5

i hav a P30 and its better than the std UT02 for distance But now iv resister modded the UT02 it blows the P30 away and has NW tint

+1 for a UT02

i noticed the D1S has choice of 3 tints , thats better than the P30 which has a xpl-hi v3 which is a little cool

6

Another plus for the U21 is almost completely flat regulated output and excellent turbo runtime with 26650.

7

OK

choice coud be D1S or UT02 modded with a lexel TA driver.
D1S doesnt step down at 1200lm
UT02 like U21 ? stepdown after 80min @1200lm

But UT02 form factor is bigger than D1S. So i would go for D1S as i don’t need to mod it for the same result.

Any other competitor ?

8

If we’re talking about modding, the choices I like are:

  • D1S with dedomed SST40. Serious thrower, not expensive
  • UT02 with TA and SST40. More expensive, throws even better
  • UT02 with Schoki’s MP3431 driver and XHP35. More efficient than the above, throws nearly as well with a little larger hotspot. I intend to build one.
  • UT02 with Schoki’s MP3431 driver and dedomed XHP50.2. More efficient than the above, throws about as as stock D1S / UT02, but with 3 times larger hotspot.

Neither of the above would be thermally stable.

9

UT02 with a battery is bigger and almost twice as heavy as the P30, for my usage that is a pretty big difference. the two things I would change about the P30 though are

  1. Neutral tint option (not a big fan of cold tints)
  2. I want to be able to switch between turbo and a lower, more sustainable level easily and often. this is where the D1s UI is awesome I imagine…

I have the P30 but I’m considering the D1s. UT02 looks like the best option for a thrower that’d live in the car (where USB charging would be useful).

10

You don’t have to use UT02 with 26650. Though with 18650 it will still be heavier.

11

I’m just curious about ‘efficiency’ (which I understand means longer runtime for similar light output).

How big a difference are the “efficiency” of the D1S vs P30 vs UT02, assuming we’re using the same 18650 battery?

12

This is not simple to estimate or even measure as D1S doesn’t have regulation. It’s powerful on a fresh battery, but progressively gets weaker as battery deplates. P30 and UT02 maintain full output until the battery is nearly dead.
To get a good hunch of efficiency one should integrate output over time.
Then, efficiency depends on mode. The harder driven the light, the lower efficiency. Well, at least somewhat. To tell how efficient a light is one should plot efficiency against output.
After doing so we’d arrive with (approximation of) a curve for each light. That’s something that we can compare directly, the higher the better.
But I’m pretty sure that the distance between curves won’t be constant, i.e. you won’t get a simple rule like “A is 20% more efficient than B”. More like “At output X A is 20% more efficient than B”.

13

Thanks for the explanation!

When reading product descriptions or reviews of flashlights, which information should I look for to find if it has regulation or not? I take it that if it says “constant current output”, then that means it has regulation. And if it says “direct-driven”, then it’s not regulated. And there are some that are a combination (eg. BLF A6, etc).

It would likely be quite difficult to compute total light output (eg. xxx lumens per unit of time, and then sum them up). But from what I understand, regulated would generally lead to higher efficiency, right?

I recall reading a runtime chart of a small database of AA and AAA flashlights and their lumens vs runtimes here:
http://aaflashlights.com/flashlight/aa/

Would be nice to have something like that with 18650 lights… might be time-consuming for someone to do though, considering these are done on their free time with their own limited resources…

14

I forgot to mention: efficiency of directly driven lights is heavily dependent on the cell used.
VTC5A will drive a LED higher than 35E making it less efficient.

That’s correct.

I don’t think that integrating output over time would be difficult really for people who do output vs. runtime charts. Though I guess most use phone apps and phone light sensors which would add a margin of error when comparing different lights. But would it be too large to invalidate the results? I don’t know.

Right. Also, efficiency depends on how it’s regulated.
In general there are 3 types of drivers:

  • linear ones burn the excessive voltage as heat (drivers that are pure linear in any mode are very rare)
  • linear + PWM run LED at high current and PWM down to the desired output. They too burn excessive voltage as heat, but also drive the LED in less efficient region than others
  • induction-based drivers (buck, boost, buck-boost) are more efficient
    • buck-boost is less efficient the pure buck or pure boost as sometimes it has to do 2 voltage conversions
    • XHP35 drivers are less efficient than f.e. XHP50.2 ones because they need to do a bigger voltage boost.

Also, efficiency depends heavily on LED choice. XHP35 is more efficient at high outputs than XP-L HI. IIRC it’s less efficient at low outputs.
Don’t forget about optics. AR coating of the lens (or lack of it) can be easily more important than driver choice. Reflector quality matters too.
Thermals matter also, though to lesser extent. Especially in lower modes.

UT02 is boost + XHP35.
P30 is buck-boost (I can tell so because it can drive XP-L with either 1 or 2 cells) XP-L. The driver efficiency is probably similar to that of UT02, but at higher modes XHP35 wins.
D1S is linear + PWM at low modes, then has a single linear mode (If you remove power and turn it on you get to this mode). Then it’s semi-regulated, PWMing between linear and direct drive. At the highest mode it’s unregulated….unless thermal control engages.