Lightweight, beam pattern, ergonomic, reliable, and ease of use come to mind. Memory, that is, having the light come on at the same brightness you turned it off is important to me as well. BTW, at the bottom of the list is having a “blinking” feature right in the middle of the on-off choices. Looking at you Princeton Tec.
I love 18650 batteries and there are a lot of current choices in headlamps with them which I own quite a few. They are nice for tasks around the home where you don’t need that much Mah/run time, but they are too heavy for getting into the deep woods where the run time would be utilized.
My primary usage of headlamps is for being at speed in the outdoors such as running, skiing, biking, so I’ll be describing a different type than most others here. I have particular concern about the most difficult light conditions, such as rain and wet, dark trails in the woods where 800 lumens looks like 50 lumens because there is so little light being reflected back to the eyes. That’s my conditions in the fall before snow arrives.
Personally, I can see have two headlamps to choose from - a lighter weight single 18650, and bigger, multi-optic lighthead with separate battery pack in back for balance (or with longer cable to a pocket on my body).
#1 is a good beam pattern with both good throw and good spread. When the throw is aimed down the trail, there needs to be light at my feet so I don’t trip over things and don’t have to tilt my head up and down to see either. It should be a continuous, smooth carpet of light between the near and far. Can be just a single optic in a smaller light, or a multi-optic lighthead with a mix of mostly narrow optics with some wider optics and/or a mule (like a multitude of two optic bike lights or orienteering lights). I particularly like what Outbound Lighting is doing with bike light optics, with the founder being a lighting engineer and doing custom optical design. But he’s not making headlamps. For headlamps, I can’t really complain about the typical round light pattern though.
If multiple optics, they all come on together at the same intensity. I don’t want to operate them separately. The purpose isn’t to have a wide or narrow beam, it’s to have it at the same time to create that near-to-far carpet of light for my usage.
Large cooling fins sufficient to get continuous output, whether that is 800-900 lumens in a smaller headlamp, 1500-2000 lumens in a medium size headlamp.
Headstrap designed with stability for running and comfort.
Dead simple UI. Low-medium-high or low-medium-medium high-high. Anything more complicated needs to be well hidden.
No moonlight (just say no to moonlight modes )
No turbo (just say no to any output that can’t be held continuously)
No blinking modes (or hidden so I’ll never get there)
No red mode
Regulated output, 2 hours at 600 lumens for the smaller
Switches to lower setting when it can no longer hold regulation - doesn’t switch off suddenly
High efficiency electronics
High reliability. Just about every light I’ve had for more than a couple years and given heavy use has failed. If cables for remote battery pack used, particular concern about vibration from the cables bouncing around while running, sub-zero F cold performance/flexibility, strain relief.
Water resistant/waterproof enough to not have any water entry in a downpour. I’m not going to use it underwater.
Onboard USB-C charging that can also run the light in a remote pack without a battery in the head. But not essential.
Centered, not L-shaped. Will never use it separately from the headstrap.
High enough above eyes (light offset above headstrap level) design so it doesn’t light up my nose or glasses when I’m wearing them.
Easy to use button/switch, even with gloves. Depends on exact design, but reaching up and squeezing the button on top opposed by a thumb on the bottom of the headlamp is easier than using a button located on the side (such as L-shaped headlamps with the button on the end when on the head).
I appreciate high CRI, but when out running in the most difficult wet conditions, the importance drops way behind beam pattern/total lumens. For a smaller light, a more efficient emitter might be necessary to get 2 hours continuous at 600 lumens. A larger light with 2x18650 or larger battery pack can be high CRI.
Color temperature 3500-4500K. I like the warmer temperatures, but willing to go more neutral for more efficiency.
Weight doesn’t factor in that much as long as there is balance and stability for running. Weight is more important for the smaller, single 18650 light than the remote battery headlamp because all the weight is in front.
There are lights like or close to what I describe. They are typically marketed for orienteering or are bike lights that can be adapted to headstraps rather than just helmets. They are typically not budget though.
Is this cheap headlamp copy of famous brand or just one of the plenty on sale?
Interesting design and enought light for close works, but I would have one with the side Red Leds at 660nm, decent driver FF-L-M-H modes, PWM free and 2xAAA instead of 3.
What’s most important to me is that the lamp and battery is separate, that the lamp has > 2000 (but preferably > 3000) lumen and a very wide beam with some throw (> 250 m) in the middle. It should also automatically dim down to eco mode when it’s about to run out of juice instead of shutting itself off. A remote control for my wrist is also nice, so I can adjust the light during activities without fiddling with gloves on buttons I cannot see. Good helmet mounts for the lamp and battery are also a must.
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