KC1 keychain light is available now

Will there also be a Ti / Cu option, like the D4V2 / KR4?

Oh please, I hope there is ! Although the balance may be really off with the large copper head and small titanium tube

Needs a 21700 version of this light, more juice for the 8 emitters.

I’m trying to understand why the LEDs are in a 4x2 arrangement. Instead of a more conventional 2-3-2 (yes, I know, one fewer LED).

Is it just to be kooky or is there some practical advantage?

We wish the light as small as possible, as pocketable as possible, while 21700 will make the light significantly bigger,
which is not our intention.

How about 2x18650 in side-by-side configuration?

Could be done by having a single head that has sockets for two standard D4 tubes.

The thought of that makes me smile. It would be ridiculous but cool. I imagine using it would look like water dousing. :smiley:

Ordered Black XPL hi raised switch ring amber backlight with magnet.

Technically ok, but when to use 2*18650, it will be hard to change the batteries, since you can not remove the screws every time to
change the batteries. Or to use the built-in charger, the light will become more bulky.

Hank can you mix mix sst and osram?

Yes, we can mix the LED, but since those two type of LEDs have different VF, not sure how well they work together.

I just want to mention this is a generally a bad idea. The Vf of a diode is dependent on its temperature, the current supplied to each type of emitter will be different and most likely not going to result in the output or beam you think it will unless the Vf is closely matched. Remember we aren’t running resistors to each LED with this driver.

I am interested in this emiter.
How does it compare to the SST 20 or E21A 2700 K ?
Is it on the green or the rosy side ?

Thanks for the info, I just liked the idea, will it be osram w1 or W2?

I also like the idea of xpl hi 2800k I appreciate you guys and of course you hank

How about adopting some ideas from Nitecore‘s EC4GTS? (pictures borrowed from here).

[quote = Hank Wang] [quote = Tubercle] Требуется версия этого светильника 21700, больше энергии для 8 излучателей. [/ quote] Мы желаем, чтобы свет был как можно меньше и компактнее, в то время как 21700 сделает свет значительно больше, что не является нашим намерением. [/ quote]

The thickness is no more than 2 mm, and the length does not increase at all if you remove the eyelet for the lace and possibly the magnet.

Hank said they didn’t want it bulky.

Two 18650 would make it much more bulky. Sure there are major benefits to 2 cells as well, but I personally prefer Hank’s approach.

This carrier tube looks nice, but it needs to be parallel 2×18650, and not serial 2×18650, like in this picture.

Hi Hank. Could you post a general photo with all possible button colors? I can’t figure out which color of the button should I choose.

I received my D4V2 Ti with XPL-HI T6 8D emitters and made some measurements to compare the max output level to other Hank lights I own. I will post them here, as a point of refference for anyone that is interested. Included, are 2 D4V2 Ti lights with Nichia 219b emitters, which I modded myself. All lights use the standard driver except the E21A lights that use the 5A CC driver.

According to my measurements, Hank's lumen values are quite optimistic. I have calibrated my setup with 3 professionaly measured lights and all Olights that I measure are spot on (Olight is known for giving accurate lumen values). That said, the lights are still very bright, just not as bright as advertised.

Here are my measurements. All values are at startup. The batteries used were a 20A 18650 and a 10A 18350.

D4V2 Ti

XPL-HI V3 3A

D4V2 Ti

XPL-HI T6 8D

D4V2 Ti

219b sw45k

D4V2 Ti

219b sw30

D4V2 Ti

E21A 3500K

KR4 Ti

E21A 2700K

KR4 Ti

E21A 2200K

18650 3693 2365 1634 1455 1041 949 775
18350 2991 1961 1478 1292 1041 949 775

The (very) first impression on the T6 8D emitters is that they are very warm and nice. They are actually warmer than the E21A 2700K but not as warm as the E21A 2200K, so I would guess they should be somewhere in the 2500K area, but I do not have the equipment to measure that. They seem to have a pleasant tint, below BBL, but next to the 219b sw30 they look greener by comparisson, albeit warmer.

Colours rendered under the T6 8D pop quite nicely and the reds are much better than the R9 value of the emitters suggests.

All in all, a very nice emitter. I still prefer the 219b emitters, but a 62.5% increase in brightness while being also about 500K warmer and maintaining a >90CRI is a definite win for me.