Flashlight comparison – Dimmable Triple XM-L2 vs USB rechargeable XPL HI (WHL #74)
China gadgets, finally
Both of these have been laying around for years now. Time for a review – we currently got a little bit of a snowy April, but mosquito season has already started and four of those bastards have made it inside my living room. No survivors And of course, those flashlights can also be used for, you know, flashlight stuff. Finding things, not tripping over other things, sitting around with empty batteries and so on…
So, the contenders:
“Roxane X6 XPL HI 1850LM 650m Type-C Rechargeable LED Flashlight IPX7 Waterproof USB Charging 26650 Powerful Searchlight – Cool White”, bought from Banggood almost two years ago at 25,56€ including shipping. Still available, but moved up to the 35€ price bracket. Actually, this was a tiny but free upgrade from the Roxane A21 XPL2 1175 lumens model that I originally ordered, since Banggood wasn’t able to deliver. This unit included a Roxane branded 26650 li-ion battery (3.7V) without amperage details. The Banggood page says it’s “4000mAh”, my charger actually indicates 5300mAh.
“Scuba Diving Flashlight 3x XM-L2 3000 Lumen LED Dive Torch Waterproof LED Flash Light Lantern Underwater 100M” from AliExpress, bought literally 5 years and 5 days ago at 21.29€ including shipping. I have just confirmed that these are still available (never been many sellers), and there are now a couple variations as well, e.g. UV units with a five-fold reflector design but unchanged body. Price for regular white light flashlights is about the same, now with VAT included, while back then no VAT was added (sub-22€). Interestingly the original order book entry says 4000 lumens, while the expired product page only says 3000. Does not include batteries at that price (2x 18650 – both protected and unprotected cells fit)
Both units are sadly not listed at the excellent Parametrek database page, since they only list brands with full websites and multiple sellers of their products. The first one doesn’t mention any brand, and the Roxane website is down (but still registered).
Well, let’s start with the LED chips that are supposedly in there.
Cree XM-L2 are 10W/3A (5mm)² chips rated at 1052lm max output and peaking at a whopping 175lm/W. Since there are a few variations in terms of color temperature and also CRI, that likely is the standard binning for the one that has the most greenish tint, but anyway. Three of them will not be able to achieve 4000 lumens without serious overdrive, so the original marketing description is busted right there. 3000 lumens – well, possible, but at the cost of driving them pretty hard.
Cree XP-L High Intensity on the other hand are smaller (3.45mm)² square chips that deliver the same 10W at 3 amps. Rated a tad higher at 1095lm max and significantly lower at 136lm/W peak efficacy. That’s surprising given they are offered in a lower CRI bin of 70 (but also in 80 and 90), so they should perform better for that banner spec number. Maybe it’s the smaller active area that decreases efficacy, but then, how can they reach higher peak luminosity at the same wattage? Anyway, using a single XP-L HI but claiming 1850 lumens is therefore BS, and contrary to the other flashlight that might be able to deliver at least 75% of the promised output, 1095 out of 1850lm is a measly 59% at best. The second brightness setting at “1239lm” is just a bit dimmer, but even that one is above the LED specs. Better still, at 4000mAh intended battery capacity, so roughly 15Wh, a 10W LED clearly cannot work for 2.5h at full power. Doesn’t even work with the 5300mAh/20Wh measured. We’re off to a good start!
Construction – very satisfied with both of them. Solid aluminium with well anodized surfaces (they’ve been thrown around quite a bit), both have O-rings at the important joints, of course the physically larger unit with the double cell barrel has more parts. Both can be disassembled from the front (not shown), with the Roxane providing easier access to the lens, while the other one probably needs tools due to tighter tolerances and no protruding rim of the threaded part. Both flashlights have a clear glass lens, so no warping, no heat generation/flux loss, and, to this date, also no damage to them.
The noname unit has a very nice dimming feature which makes it still my #1 unit used – there’s a small slider where the other got a regular button. That slider has a small magnet underneath, and I very much believe there’s a Hall sensor sitting near the head unit control PCB that is sensitive to the slider’s location (that block has an orientation, beware!). Without separate buttons, the brightness can be adjusted in many steps from full blast to off. It is not fully stepless / hasn’t got infinite steps as advertised, maybe the sensor is but the controller IC ADC isn’t, but for all practical applications it got more than enough adjustment gradations. It is advertised as an IPX8 unit (no dust protection at all, but permanent immersion in water at a minimum of 1m), which doesn’t make sense, but with all the seals it should be fairly waterproof. The adjustment slider rail has no connection to the inside, so that doesn’t compromise the entire case.
The Roxane in contrast got a regular button (I would assume a soft button, no full clicky switch that disconnects the battery entirely) plus a tiny indicator LED: While the LED is somewhat useless due to arbitrary thresholds in the various modes, it does indicate a very empty battery nicely, at around 3.1V (blinking red). It also got an USB-C port opposite to the switch that can be used for charging (I don’t think it can be used for powering other devices, like some oversized current models do). It got a silicone flap for protection, but unless that port is protected again on the inside, I think that will break the “IPX7” rating down to around IPX4 (“Splashing of water”, water jets are IPX5 already). It should also be fairly dust-proof, but they’ve chosen an X (“no protection”) rating instead.
Roxane: Quick init phase at 2mA, then 3.7µA idle power draw. So that button likely is a soft button.
Modes: 0.09A, 1.01A, 1.9A, 2.7A (4.2V input each, but roughly constant current, so dropping power with dropping battery voltage.). Modes are saved, current does not exceed the LED specs. Interestingly there are also undocumented strobe and SOS modes when hitting the button in quick succession. Those use 1.0A of current (strobe, likely 50% duty cycle, so 1.9A when on) and 1.9A for the SOS. Clicking again will return to normal modes which is important to me, since strobe is a total nonsense feature imho.
The battery warning LED changes to red at 3.2V under load and blinking red at 3.0V under load, so that leaves enough headroom. It can only go down but is reset on mode change, so even if the battery (or power supply…) recovers at the lowest mode, it will not go blue again, even at 4.2V. This also makes the battery warning dependent on the internal resistance of the battery used, since voltage drop will be affected by the current used – larger internal resistance equals larger voltage drop and earlier warning. There’s a hard cutoff at 2.85V with forced low mode below 3.0V, so you won’t be standing in the dark all of a sudden.
Noname: Since there is no button, there are no special modes. While that is dope, the idle current consumption isn’t: It’s gulping 3.4mA permanently. Not µA, mA, so 1000x that of the Roxane. Likely an effect of the sensor, meaning my regular 2000mAh protected batteries last 24 days without use. That sounds about right, since they go flat at a strikingly high rate even without much use.
The lowest power mode (all tested at 8.4V) is 7.3mA, so 3.9mA going to the actual LEDs. That’s extremely good in my opinion, given the maximum current is 2.2A or >500-fold the smallest setting. Translated into wattage that however is only 18W, so no way the 3x10W rated LED front end is even close to outputting 3x 1000 lumens. Eyeballing from the extensive datasheet, that could be around 260% of standardized flux at 700mA or ~700lm depending on the exact color and tint bin. 3x 700lm is…2100 lumens or 53% of advertised value. Well, we’ve had that level of scamming with the other flashlight as well, right?
Unfortunately there is no low-voltage cutoff, it will work down to 3.1V (1.55V per cell) where the circuit board likely goes unstable. There’s also no power compensation, so a current setting is used from full to empty batteries and flux output drops accordingly, just like the Roxane does.
A word on those values, though: Both units will not tolerate 100% output for extended periods of time, they do not have sufficient heat sinking and will get too hot to touch. I don’t think they have a thermal cutoff, and unfortunately they also do not feature a tactical crown where one would see some light when it is on but sitting flat on a table, so it is very important to never just set it aside when on and then forget about it – it might damage the LEDs, the driver boards, or even the lithium cell(s). The Roxane doesn’t have enough total output, but the red noname provides a significant amount of radiative heat when just moving your hand across the LEDs…which allows for a secondary mode of operation:
Well, at least the small, annoying ones, it’s not exactly an entire rising sun (although blindingly bright any time of the day). So if one of those pesky mosquitoes sit on your wall, just approach with overall lights off, and the flashlight on a pretty low setting. In more than 95% of cases, they won’t fly away – that would be conspicuous, right?
So once the light is close, just sit it flat on the wall in a quick motion (try not to squish the possibly blood-filled gnat onto the wallpaper…). And then move the slider to the opposite side…
What a great portable desiccator! Let’s say 1/4 of those 18W go towards the wallpaper in heat and light, that’s 4.5W or 4.5J per second. According to the Googles™, a typical mosquito is only 2mg (let’s assume it’s 100% water), and the most resilient animals on earth can tolerate 50°C for a short period of time, so 30K delta from room temperature. Good news: With just 1/4J of energy absorbed over a short amount of time, that mosquito is parboiled. The flashlight deposits that amount 18 times per second. Even if just 1% actually heats up the mosquito and 99% goes to the wallpaper, job’s done within five seconds. And that is roughly what can be seen, well, heard, in practise. Buzzing goes to ludicrous speed, imaginary microwave-pling-sound, and it’s cooked. Best of all: It’s not squished. Even these specimens full of blood just drop down on the flashlight rim and can be removed without a stain. I still wonder if some day, under the right lighting conditions, someone will look puzzled at my wallpaper and ask why there are literally dozens of round, ever so slightly off-colored spots of the exact same size randomly distributed all over the flat…
It also does work with regular flies, but since they are in the order of 50 to 100x heavier but have significantly less than 50-100x the size for absorption compensation, those take way longer to fry. A good old fly swatter is recommended instead, plus you don’t torture the (fucking annoying) animal longer than needed AND there’s no evaporation stains on the lens…
Well, what’s missing? Beam shots. I need to take them outdoors at night, but since we do have a lot of snow left, that would significantly spoil the results. I’ll add them as soon as I can!