I wonder if anybody would be willing to measure what currents the HS21 draws at different settings and levels, at first?
I would agree that the IR feature in this light is stupid (or to put it more politely - not very well designed). BUT I would not say that IR control when implemented properly in a headlamp is a bad idea. It can be a very useful and desirable feature. I had an old headlamp with IR control and it works very well as follows:
- IR can only turn it on and off. IMHO, this should be a primary requirement. My common use case is working on something where my hands get dirty (engines, painting, chemicals, etc). I don’t need to change brightness or modes - I just need to turn the light on when I need it and off when I don’t without smearing grease or paint all over the light - or my head.
- When IR mode is enabled and the light is turned off using IR gesture, it will stay in IR mode for 10 mins - after which the IR circuit will auto power off and will have to manually be reactivated by a button. Using the IR sensor to turn the light back on within the 10 minute window will reset the timer.
- IR sensor only works within about 2-3 inches which eliminates most of the undesired operation when getting too close to something. Also, the IR sensor is forward facing which also helps.
- The sensor is immune to activation from ambient light sources. This is likely achieved by modulating the IR emitter and triggering the IR receiver only when this modulated signal is detected.
IR control is marketed by Sofirn as a key feature of this headlamp, but from reading this thread, it seems like most folks won’t use it since it doesn’t work very well and is missing the key feature of being able to turn the light off AND on. It is a cool gimmick and will give flashlight enthusiasts a new toy to play with. It does look like a great headlamp if you ignore the IR marketing.
I was really hoping this Sofirn would be an upgrade to my old IR headlamp, but unfortunately it won’t. Maybe V2 will improve the IR control to make it more useful.
What’s the old headlamp with the on/off IR proximity sensor?
It was a decade old Olight. Not sure of the model. Really crappy emitter (dim, bad tint) and short battery life.
Olight does make some newer IR controlled headlamps, but I have avoided buying Olight products for the past decade and would rather not buy another. They make an IR model where you turn it off and on by waving your hand left and right and change the brightness by waving your hand up and down. Neat concept - but some of the reviews say it is not that reliable in practice, although others say it works well.
I’ll definitely give this Sofirn a try if/when they add on-off IR control.
Hello,
why without magnetic tailcap?
Sofirn sells replacement magnetic caps, but I’m not sure which one could fit this light, if any.
I was thinking of simply inserting a neodymium magnet into the standard cap, but I don’t think it’s feasible.
The only other option that I can think off is gluing a flat disc magnet (25 mm diameter, and there are 1, 2, 3 mm thick versions) to the bottom of the cap on the outside. Since there is no separation between the magnet stuck outside of the cap and the object, and the 25 mm magnet has a pretty large surface, I think that the magnet doesn’t need to be thick to hold - so maybe something discreet like 1 mm thick, black coated magnet could do?
One experience with gluing neodymium magnets to metals is that roughing and degreasing both surfaces to be glued makes a big difference for longevity. I tried epoxies, but had better luck with good cyanoacrylates - I liked the Locktite Ultra Gel.
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Just a thought - maybe a magnet could be useful. I bought a few extra brackets - the intention being that I would use this lamp as a clip-on to the bike, backpack strap, or the headband. With a magnet you can stick it to many other things around you - and you can rotate the emitter around, just like in an L-shaped light, to aim it at where you work.
Magnets interfere with a Compass.
Cavers use headlamps with No Magnets, because they navigate with a Compass.
Hikers who use a Compass should not use lights with magnets. And should not pack a Compass with anything that has a Magnet on it.
I think Sofirn got it right by Not putting a Magnet on the HS21 Headlamp.
That may be true, but for a caving light it may have to become a little more water resistant 
Two dials solution will do it all! I’m sure…
Mate, I don’t agree with You that shape of flashlight determines appropriateness of using magnet.
With this line of thinking, it can be assumed that in stright flashlights (ordinary or headlamps where the optic is tilted 90 degrees) there is no point in using a magnet because they fit perfectly in to the hand. And theres a lot of flashlight with magnet.
Another thing is that they are T-shaped flashlights with a magnet.
As for me, I use a magnet in flashlights very often. In a situation where I want to have my hands free, especially when I want to illuminate larger area, for example a table next to a my fire camp. I stick a knife into old tree and attach a flashlight to it. Then i have entire table where we eat illuminated.
As for the compass. I haven’t used it so I don’t want to comment. But it’s hard for me to imagine that the magnet in the headlamp would affect its operation. But, as I wrote, I have no experience in this matter, so this is only my opinion.
But honstly, for me there is no point to argue in this case.
If it will be possible to buy optionally cap with magnet. Everyone will be satisfied.
Sorry for my poor English
Cheers
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This is an interesting question: how far away does a small neodymium magnet need to be not to worry about it interfering with a compass?
Here is my stab:
- the Earth magnetic flux density at the surface is some 50 micro teslas. This is what compasses go by.
- a flat disk neodymium magnet may be some 1 tesla near its surface. Such disks may have a characteristic length (i.e. along the magnetic field lines) of maybe 2 mm
- the strength of magnetic field decreases roughly as inverse cube of distance, at least in the far field.
- So I figured, roughly, that the distance of around 5 cm from the magnet will probably reduce its flux density to a level similar to what the Earth is producing. Some 25 cm should reduce it to less than 1% of the Earth magnetic field.
If I didn’t mess up the estimates(?), it suggests that it doesn’t take that much distance to render magnets benign compass-interference wise - a forearm length is more than enough. Is that true?
p.s. And a true anecdote: I had a wrist watch with a mini compass on the strap, next to the watch. Unknowingly to me, a little spring pin that holds the strap and was next to compass, was magnetised and that definitely interfered with it - but I found out about it after a while, the hard way (not that hard - just a lot of silly walking without any sense of direction, despite having a compass).
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Here is a review of another headlamp - HD16, by @Weerapat_K. The reason I quote it here, apart from the HS21 also being shown in this video, is that HD16 has a side rotating dial. The dial is used for mixing Spot and Flood intensity (except for red, where it works as I believe it should). The reviewer likes the idea of the side dial, but, as he mentions it several times in the video, would like it to adjust the light intensity instead. Just like I proposed for the HS21 (except I think indexed dial instead of a stepless one would work better as this would have a smaller, more ergonomic turning angle as opposed to turning it round and round) - couldn’t agree more.
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Did you happen to measure the parasitic drain when the light is off, by any chance?
I wonder if the rotary dial uses a Hall effect switch or it’s mechanical somehow - but then how that can be made water resistant even to IP66 level (or if you go by what’s on the box, IP65)?
1.88 mA, which is extremely high. After 1600 hours (66 days) a 3000 mAh 18650 would be empty.
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Cheers for that! What’s the most likely reason for it? I was thinking the Hall effect switch, but then it would be on the mode dial and wouldn’t have to be powered when the light is off. Then there is the IR sensor, but that’s also off by default.
Don’t know, maybe the hall sensors, maybe programming error (MCU does not go into deep sleep mode), maybe some bad driver design.
Is it possible that it goes to sleep after some time and this may be lower when measured then?
On paper this light seemed cool, but now it feels to me like Sofirn are shoving too much into it.
I wish they (or some other manufacturer) would make a T-Shape headlamp, with good regulation, single emitter (with optics for all-purpose/mid-range beam, and a decent UI. I like Anduril but it’s not absolutely necessary. In fact I like the idea of this HS21’s rotary dial too (even though it doesn’t have the same type of rotary power control like an HDS or Jetbeam RRT-01).
A pared down version of this HS21, simplify the feature-set, decent UI. That would be a dream for me.