January 23rd, 2013

Hand warming and blinding device that is trying to get you killed (with a complimentary flashlight)

Ok, so I had a chance to play with Zebralight H600, and it is a great flashlight (and great gift from my great girlfriend). Unlike Petzl Nao, it is small enough to fit under the helmet, so that you can actually use it for riding. Ouch, and packing is also way nicer than Petzl; simple cardboard box, not bloated paper box including paper and embedded magnets, with big sticker touting how environmentaly friendly it is. Zebralight is actually friendly, Nao just claims so.

So far so good. I actually like this flashlight. Now... the blinding part. This beast has 750lm, in pretty small package. Activated by single short click. The battery contacts had some problems for me, I tried to troubleshoot, and of course I got "hit" by 750lm beam from close distance. (Fortunately not by the center of the beam). Results are not nice.

Perhaps short click should activate the lowest mode? Or perhaps... when going to the highest setting, it should turn on the power gradually, so that eyes have chance to get evasive action?

Single short click while the light is on turns it off. That is nice; no clicking through other modes (including high-power) when turning of Nao.

Now, normal 18650 fit into the Zebralight. (Good, no custom accumulator as in Nao case). I got dx (sku 5776) TrustFire Protected 18650 Lithium Battery 2400mAh, and dx (sku 47499) Universal AC Charger for AA/AAA/6F22/18650 Battery (AC 100~240V/EU Plug) charger. Despite advertising EU plug, charger will not actually fit into EU socket, but that can be worked around... batteries work as expected, and they are protected. Which is actually bad bad thing.

So.. primary use for the headlight is horseback riding... and for that I need light that stays on. 0.1 lumen is okay (actually, sometimes it is too much, but it is still way better than 10+ minimum mode on Nao), but you need some light so that a) hunters don't shoot you b) cars don't hit you and c) you don't hit any branches.

Nao tried to scare up my horse by doing three bright flashes when battery went low in low-power mode. (Successfully). But then it kept shining... and when the battery went really low, it kept shining without ability to turn it off. Not nice, but that one did not try to get me killed (well except for trying to convince me to ride without the helmet).

Zebralight is another story. So far testing was done at home, battery lasts about 110 minutes in 420lm mode, then goes to 21lm mode for 10 minutes, then goes to lowest mode (0.1lm). It gets hot (as in "too hot to touch") in the first part of the test, and I was not even running it in 750lm mode for more than 6 minutes. But the bigger problem is behaviour at the end of cycle.

Single click activates high-power mode; but the battery can not support high power mode, so current is quickly limited. So far so good. But do it few times (and it is very easy to do by mistake), and current limiter fails to limit it quickly enough, tripping the protection in the battery. At that point, battery has 0V, and you are alone in the dark. Say hello to cars and branches, and try not to look like a pig.... (You can't blame the battery; it is down to 2.8V at this point).

Zebralight is great flashlight... but not going to full power mode on short click (or some other way of improving low-battery behaviour; it already has CPU and knows battery is low, perhaps it could limit to lower-power modes from that point to battery removal?) would make it even better. (How do I update its firmware?)