[Group Buy Interest Poll] Tiny EDC keychain light done right - BLF/Sofirn-style!

Rovyvon lights are larger than the smallest AAA lights out there while having half of battery capacity.
(And they are dimmer than the brightst 10440 lights out there).
Though to be fair - they are smaller than the smallest rechargable 10440 lights out there.

Some photos to illustrate what I mentioned above, about the DQG Slim Ti!

So, what about the possibility to create a light that can be like this but slimmer (10180 and/ or 10440)?

at Agro

Yes, the RovyVon Auroras are larger than some of the smaller AAA lights (maybe the Olight is the smallest one), they are dimmer than the most powerful 10440s (the upgraded Folomov is the best example), but they also offer in-built recharching and, depending on the model, they offer quite nice “alternative lights”, such as UV, red, blue or even side white light that most of the times is enough for daily tasks.

Don’t get me wrong, I am just saying that for me, this project has to stand out to make me use other lights than the RV!

I am keeping an eye on it, though, as it is interesting to see how it progresses and where it will “end” (starting the lights’ production, I hope!) :wink:

So, thanks for your contributes on this :wink:

Interested in 1:)

I agree, clear anodization (or perhaps no anodization) would be a good choice for an Al variant.

With visually linear mode spacing the perceived brightness change (or step) between low and medium is the same as the step from medium to high. In other words: the medium mode is perceived to be right in the middle between low and high. It's simply pleasing to the eye :cool: . On many lights the medium mode (or the middle modes on lights with more than 3 levels) is brighter than it would be with visually linear mode spacing resulting not only in a small perceived difference between medium and high, but also a much reduced runtime for the medium mode. On lights that don't have perfectly flat regulation it gets even worse with depletion of the battery, to the point were you are asking yourself if it is necessary to have two different modes that are barely distinguishable from one another.

Simply put visually linear mode spacing is a sort of "ideal" (that's why I like it :) ). While it is of course not necessary to stick to this ideal, I personally think it is still a good idea to make sure you don't deviate too far from it in cases where you need or want to select brightness levels base on other considerations (such use case or specific runtimes). For example: on a 3 mode light with a low of 1,5 lm and a high of 150 lm the ideal (i.e. visually linear) medium would be at 15 lm (constant factor of 10). If you want a higher medium (most people are used to this since the majority of commercial lights have higher than visually linear medium/middle modes) 1,5 | 25 | 150 lm would still be just about acceptable in my view (factor 16,67 between low and medium and factor 6 between medium and high). A spacing of 1,5 | 50 | 150 lm on the other hand would be too far from the ideal in my view, huge gap between low and medium (factor 33,33) and very small gap between medium an high (factor 3).

In case anyone is interested in more details, have a look at "Stevens's power law" and the chapter "The Human Visual System" in the "LED Flashlight White Paper" by Henry Schneiker (founder of HDS Systems).

Regarding QTC:

Many Years ago I bought a Veleno Designs Quantum D2 (a small 10180 light with QTC brightness control). On paper it sounded great, but in practical use it left me a bit underwhelmed (I sold it after only a short period of time). The brightness control was finicky, when twisting the head the brightness jumped around and it was difficult to get to a specific brightness. The main reason for this undesirable behavior is the play in the threads, so ideally you would want very high precision threads with next to no play on such a light (which is of course not possible on a budget light since it would drive up cost massively), not to mention other concerns like the durability, availability of replacement QTC and the force/tightness needed for full brightness. In short I would vote against QTC.

I like the side switch in the above flashlight but I would really prefer switch to be a little bigger:

something like the one here: UltraTac K18 Mini

And I still think that flashlight that would works on both 10440 and NiMH AAA would be a winner:
something like the one here: UltraTac K18 or Jetbeam E01R

Quantity I would buy: 3 (if side switch and price below $10 and runs on 10440 or NiMH AAA)

I have absolutely zero interest in keychain lights. Just sayin’…

I would also vote against QTC.

As far as the Hobi+, it’s available with an extension tube for 10440 support. It won’t change the brightness but it will get you runtime if that’s your thing.

As far as this light, I’ve decided I’m not interested in an aluminum version. However, I hope things go well, and that a Ti version comes along…

I worry about the tint on that SST20… I dream of 219B but I fear it can’t be reliably sourced.

rost333 I think you’re looking for a very different light. Nice pictures though.

pooptoast Strange. I wonder if there are reliability concerns with USB charging circuits. At least you’re getting a replacement.

PBWilson It hasn’t been discussed, but I’d expect the charging port to end up under the threads. Certainly that is my preference too.

MascaratumB Thanks for the info and review of the DQG slim Ti! In general the addition of USB charging adds length, so that’s something we need to keep in mind since it is a majorly desirable feature.

I have some concerns with the DQG: 1) that diameter (a bigger problem than moderate length) starts to get uncomfortably large for a pocketable light, 2) switch reliability as mentioned in your thread is worrisome, 3) the tube extension and battery options suggest a different usage target than for keychains.

As pointed out by Agro, the size approaches AAA lights (especially if you add USB charging). I have a hard time justifying these in-between sizes since to me they seem like the worst of both worlds: too big to compete in size with 10180 keychain lights, and too little capacity compared to AAA. Maybe there is some niche for them… I just don’t see it yet.

Noir I understand that visually linear levels look more natural, but wouldn’t it be more important to select functionally useful levels? Do you find 10-15 lumens to be enough for most keychain light use? Nice links btw.

beggindog It takes all kinds to make a world. :slight_smile:

Scallywag Stainless steel and titanium versions are possible at a higher price . :wink: [Group Buy Interest Poll] Tiny EDC keychain light done right - BLF/Sofirn-style! - #91 by phouton

This is actually a great feature. Tubes are cheap, heads are expensive. With a shorty tube you have a light that’s comfortable to carry and still has enough capacity for many short bursts. Extend it - you suddenly have way more capacity at the expense of extra bulk.

Great idea. I’d probably shoot for the smallest tube for a keychain light but I could see a longer option and longer runtimes a plus for some folks I know.

Tint is important to me (4000K preferred). Not really interested in high modes, but I’d want a decent moonlight mode. Preferably in titanium.

And if possible a separate charging adapter, like the DGQ Hobi has.

I just signed up to say that I’m interested.

Battery: 10180 lithium ion replaceable.
Dimensions: Goal is to limit to roughly 40mm x 14mm and ~12g.
Price: $10-$15 Tops

I wouldn’t need anything else. No exotic materials. Aluminum in some colors (black, red and so on…).

Basically something that really works and tiny. No need for more.

Edit: I ’m reading a lot of comments asking for a lot of things that IMO won’t happen under $15. So I think the idea is to make something that it’s not in the market yet: something tiny and reliable but cheap. Most of the lights with similar details are about $30. If people want a tillion modes, and exotic materials, and tube extensions and so on for $10 it’s not gonna happen.

I would be in for 2 depending on the final price.

Interested in 1 for now.

tacocowboy Welcome to BLF! Yes, there is a strong emphasis on keeping the price low, and the light simple to use while being open to accommodate enthusiast features as much as possible within those constraints. Expensive or niche features almost surely won’t make it, or will be in different more expensive versions (i.e. other materials).

Flying Luminosity Curious why you’d want a separate charger. That’s been offered with many flashlights for a long time. You can always buy a dedicated charger. The point of built-in charging is so that it’s always with you to charge on the go, and so that it doesn’t get lost.

I like something like the Nitecore Tube BUT I’m tired of it switching on in my pocket all the time so some other foolproof switch would be a big plus for me.

Mine has a lockout. Works very well.

Also in for one.

One interesting option would be to figure out what kind of optics does TrustFire use in their MINI3 and use that as well.
It is very flat, would reduce the light length by 2 mm at least.
Beam shape would be…unusual.
It’s somewhat similar to a SMO reflector in that it has distinct narrow and wide beams.
Hotspot is sharp and much like in a not-fully-focused aspheric.
Wide secondary beam is similar to spill of a reflector light but it’s not actually spill and it’s very wide, nearly mule-like.

Honestly, I’m not sure if it’s great beam shape for such light. So I won’t call it good or bad but merely interesting. :wink:

Interested!

Interested in 1 or 2 pcs depending on price.
Design suggestion: aggressive knurling for better grip and twisty action.
Thank you!

edit: I’m ok with sealed battery BUT would appreciate if it was somehow serviceable/replaceable to replace it if/when performance drops consistently or fails.