KC1 keychain light is available now

Maybe do both voltages, so you can hit multiple emitters with 12v and at the same time keep the efficiency of the 6v b35AM.

My Getician 4500k in the Acebeam E70 is beautiful, but paying for premium metals (ie brass copper and titanium) makes it ridiculously expensive $150-180+

Well they’re gonna have a 12V version anyway since XHP35 is apparently already planned. The driver itself only needs a few components changes between 6 and 12V (Rsense, Vsense divider and maybe compensation passives), but it’s true that having only one version is advantageous because it means only one variant to manufacture and handle. Although it seems that Hank prefers to actually have multiple driver variants rather than modify the current in software in the case of the 5A,7.5A, 9A linear drivers where one resistor is changed to set the current.
Difference in efficiency can also be minimal, I was thinking of the TPS61088 where the efficiency at 12V is significantly lower, but with other converters like TPS61288 or MP3431 there is not much difference.

Freeman, thank you so much for your input here. I always really appreciate it because it's so informative. I'm glad to hear that the 12 V xhp35 hi is already on the table. I'm also glad to hear that if this other MCU (?) Want to be used at the efficiency would be somewhere between 6 V and 12V. That is great news, and I know it's a lot more manufacturing and maybe more cost for Hank but it is nice to have multiple drivers for us to, because Hank will sell us parts and drivers and we can mod his lights and other things with his fantastic creations.

Most multi-cell lights with rechargeable cells use the cells in parallel, I think, which decreases the hazard of reverse charging a cell and maybe igniting it. So 12 volts would need a boost converter. A fancier approach could involve independent voltage monitoring for each cell, but that would be hard in the traditional tube-shaped flashlight format (maybe better for soda can) and would would require more software that would have to be tested thoroughly.

Hank, thank you for responding to feedback here for influencing upcoming designs.

There is one general area of improvement that everyone will want, even if they don’t know it yet, and that is a different AR coating. Currently, the coatings reflect a disproportionate amount of red and blue, and very little green. This causes the Duv to increase by a small but noticeable amount and makes it harder to achieve ‘green-free’ light output so many enthusiasts desire.

If the coating is changed to a variety that reflects more green than other wavelengths, this behavior can be flipped. Duv will be lowered slightly and LEDs like SST20 and SFT40 that are hard to find without a green cast can be made more neutral.

The difference between two different lenses that behave in opposite ways can be as significant as 0.0050 Duv.

I completely agree. I prefer to have no AR coating rather than most coatings that I’ve seen.

Thank you JaredM For bringing this AR coating topic up to Hanks attention.

I think Hank already solved this years ago. It has been a while since I measured one, but ever since the gen1 Emisar lights, I’ve found that Hank’s lenses are either clear or a non-green coating.

Here’s an example. Left: Emisar D18 (nice AR coating). Middle: Emisar D4S (no coating). Right: old EE X6 light with a bad AR coating.

Looking closer, here’s another bad type of AR lens next to an uncoated lens: Fortunately, it’s only one-sided, so the effect is half as strong.

That type on the right looks violet when reflecting light at an angle as shown above, but when light passes through it turns the light green. So it produces green beams. Here’s a particularly bad one from an old Olight:

Left: Olight green-shifting lens. Right: uncoated lens.

… and here is a Noctigon K1, with a much better type of AR coating:

I still prefer a plain, uncoated lens for most lights… but as far as AR coatings go, Hank’s are some of the best I’ve seen.

Do you mean that we should use the non-AR coated glass lens?

Thanks for your input as always TK! I was not aware of the history of AR coatings Hank has used on his lights, but I have heard recent reports that a KR1 lens was responsible for a +0.0015 duv shift. While this isn’t Olight levels of bad, it still leaves a bit to be desired.

I do agree that his coatings are definitely top tier. I haven’t ever noticed the high angle colored artifacts like Convoy (magenta) or Eagletac (blue) lenses have.

It is apparent that both the D18 and K1 are still reflecting predominantly golden>orange>rose colored wavelengths. If this could be changed to green I still think this would be better.

Pursuit of perfection! :innocent:

Lastly, I also prefer ultra clear (low iron) uncoated glass for hiCRI lights. I wasn’t aware Hank offered uncoated glass already.

This would be a nice option to have, especially for use with hiCRI emitters.

This photo is credit is to g_damian in the WT3M thread:

The right AR lens is an example of what is desired. Green reflections. This helps remove some green tint from the beam.

I measured several recent lenses with my spectrophotometer and got arround +0.0010~+0.0015.
An old D4S lens was ~+0.0030.

So yes there was an improvement, but it should be possible to get even better AR coatings. Djozz showed measurements of a lens with green reflecting AR coating (or rather it’s just that the AR is more effective on the blue and red ranges, since the point of an AR coating is to increase overall transmission)

Here is an article about AR coating and different types of them with different transmission depending on wavelengths.

Preferably the lens should not affect the tint or if it does, decrease duv (less green, could be even better), a quality plain lens does that cheaply, with some transmission losses vs AR coated lenses. The best would be an AR coated less that allows max transmission with good tint, I guess it depends what your suppliers can do and at what price, although the flashlight with green reflecting lens Djozz tested above is a cheap one.

As an option while ordering would be great!!!

Hank is it possible to have a lighted switch both on your new thrower and the upgraded D4Sv2? New hardware and firmware for it is great, but adding a lighted switch and premium metals options would be the cherry on top.

Is it normal to have an order in Hank’s shop in processing status for more than 2 months? :weary:

I would say probably not. Have you emailed Hank? He’s generally very responsive.

Just ordered a DT8 with 90CRI LH351D 5000k - very much looking forward to it!
Review of the Noctigon KR1, with detail on strobe modes: https://www.stephenknightphotography.com/post/flashlight-review-noctigon-kr1

Given that Lumintop have managed to screw up the FW1A yet again, it would fantastic if Hank could produce a mini-Noctigon KR1, same build quality, 18650, tail switch, but with a more pocketable 25-27mm head.

I hoped new thrower will be like you said stephenk.

I believe a 21700 pocket thrower is the next hotness