Disclaimer: The Vollsion MR12-D was provided for testing by the manufacturer at no charge.
The MR12-D is a part of Vollsion’s new line of rechargeable lights with a power bank function (the -D in the end). The same light comes in two form factors, a throwier MR25-D with a bigger head and the classically straight tube shaped MR12-D tested here.
Features and manufacturer’s specifications
Battery: 18650, the light comes bundled with a protected 3400mAh cell
LED: Cree XP-L2 in cool white (actually XP-L)
Waterproof: IPX8, 2 meters
Impact resistance: 2 meters
Mode memory: yes
Micro-USB charging and power bank function with included OTG adapter
Manufacturer’s output specs
Maximum output: 1180 lumens
Other output levels: 300/30 lumens
Special modes: SOS, strobe
Light intensity: 18600 candela
Beam distance: 245 m (doesn’t match indicated cd)
User interface
The operation of the light is very simple and easy to grasp immediately. It works identically to the Thrunite TC12 V2. The tail switch completes the circuit and turns the light on. As it is a forward clicky you can press it halfway for memorized momentary. The gradual output increase when the power is turned on makes especially the high momentary just a bit too slow. The electronic side switch is used to cycle modes. The switches feel great with no mushiness.
From off:
Full click of the tailcap switch turns the light on at the previously used brightness (strobe not memorized)
Half press for momentary on the memorized mode
From on:
Single click of the tailcap switch turns the light off
Short press of the side switch cycles through output modes (low, mid, high)
Long press (~1 sec) of the side switch activates strobe (alternating frequency)
While on strobe, single click returns to the previously used mode
The side switch is lighted when the flashlight is turned on so you’ll never lose the position.
Physical appearance
The Cree XP-L2 XP-L with a smooth reflector.
I’ve heard some lewd comments about the USB rubber cover.
18650 battery and 18650 lights from the left: Zebralight SC600w III HI, Olight S2R, Olight S30R III, Convoy S2+, Armytek Prime C2 Pro, Thrunite Neutron 2C, Vollsion MR12-D, Eagle Eye X5R
So yeah, Vollsion MR12-D is a big 18650 light, but no bigger than other double switch usb rechargeables like the Thrunite TC12 V2 and Eagle Eye X5R.
The head and reflector come off easily with some straps.
The head inside diameter is 18.9mm, but the MCPCB is 20mm. That’s why they’ve had to grind some of it a bit bigger. The reflector pushes the board down and holds it in place. The gasket fits very well.
The driver is 20mm. With a slightly protruding positive terminal. Flat tops do still work.
Threads are square and well lubed. Overall the finish feels rugged and the materials used are thick.
Vollsion UPL-18-34 battery
The Wh marking on the wrapper is underselling the real capacity.
The bundled battery is a high quality (and “really reliable stuff”) rewrapped Panasonic NCR18650B with added protection circuit and a nominal capacity of 3400mAh. The protection PCB adds some resistance (~15mohm) to the battery. Using a high current battery gives some output gains.
UPL-18-34 measurements with 1A discharge down to 2.8 volts
Capacity: 3188 mAh / 11.135 Wh
Low voltage protection: 2.45V
Over current protection: 8.2A
Internal resistance: 78mohm
Protection circuit comes with a button top, but the light works fine with some flat tops I tested (VTC5A, VTC6, GA).
Panasonic NCR18650B under the wrapper
The protection circuit is on the positive end.
Integrated charging and power bank
The USB charging works with any 18650.
Charging a completely depleted battery takes about four hours, which is about the same as charging it at 1A in a separate charger. In the light the current starts off high at 1.8A from the USB power supply but slowly declines until it terminates at 170mA.
What sets the Vollsion MR12-D apart is the power bank function, which works from the same USB charging port via an OTG adapter.
The Micro USB charging input also acts as a power bank output using the supplied OTG adapter. The adapter can be placed either on the light or on the device being charged. You’ll also probably misplace it at some point. I had to search for it multiple times during the review process.
As a power bank the light is able to charge an iPhone 6 to full (8.4Wh) with 0.78Wh to spare. Total conversion efficiency is decent at 82, but the dc-dc converter can’t handle 1A discharge current with low battery voltages so the last 30 must be extracted at a lower rate.
Charging an iPhone 6 from 0% to 100% takes about 3 hours after which I turned the display on and started an app to deplete the rest of the power bank.
At 1A constant current discharge, the output voltage starts to decrease at fairly high battery voltages before an hour has passed. This slows down charging. When the USB output had dropped to 4 volts, the battery resting voltage was at 3.45V.
Beam and tint
Domed Cree and a small smooth reflector usually results in a variety of tints. The Vollsion is no exception. The hotspot is a cool but neutral white, the corona around it has a warmer greenish tint and the spill is even cooler than the hotspot. The tint is better (more neutral, closer to the black body radiator line) on higher modes.
Tint in different parts of the beam.
Tint in different brightness modes.
The beam in practice is quite similar to a Convoy S2+ using an XP-L HI emitter. The Convoy throws a bit further and my version is a neutral white 3A tint. Their total lumen output matches quite well too.
Color rendering
For spectral information and CRI calculations I use an X-rite i1Pro spectrophotometer with HCFR, Babelcolor CT&A and ArgyllCMS spotread for the graphs and data. For runtime tests I use spotread with a custom script and an i1Display Pro because it doesn’t require calibration every 30 minutes like the i1Pro.
CCT = correlated color temperature, higher temperature means cooler (bluish)
CRI (Ra) = color rendering index consisting of 8 different colors (R1-R8), max value 100
CRI (R9) = color rendering index with deep red, usually difficult for led based light sources, max value 100
TLCI = television lighting consistency index, max value 100
CQS (Qa) = Proposed replacement for CRI, RMS average of 15 color samples
CRI2012 (Ra,2012) = Another proposed replacement for CRI, consists of 17 color samples
MCRI = Color rendering index based on the memory of colors or 9 familiar objects
NEW Read more about the IES TM-30-15 method
TM-30 = The newest color rendering method using 99 samples. Preferred for comparing LEDs.
TM-30 (Rf) = Accuracy of colors, fidelity index. Replaces CRI (Ra).
TM-30 (Rg) = Gamut of colors, saturation index. Higher number means more saturated colors.
Tint dev. (“Duv” in the CTA screenshots) is the tint’s distance to the black body radiator line in the CIE graphs. The higher the number, the greener the tint. 0.0000 means absolutely neutral white and negative numbers mean rosy/magenta tint. Anything over 0.0100 can be described as visibly very green. Under 0.0050 is usually satisfactory.
If you have an hour to spare, I recommend watching this presentation on IES TM-30-15 which also shines light into color rendering in general.
Color rendering on maximum output.
Output and runtimes
The output falls a bit short from advertised (1180 lm). A good battery will increase the maximum output a bit. With an unprotected Sony VTC6 I measured 976 lumens at switch on and 947 lumens at 30 seconds. This is about 10% better compared to the Vollsion battery.
The high mode steps down at two minutes regardless of cooling. Mid is visually stable for three hours after which it starts to decline. Efficacy is very good in its class.
All lights tested for efficacy (lm/W) at the mode closest to 400-600 lumens.
PWM
Vollsion says the driver uses constant current circuitry without flicker. I measured 31.2kHz switching frequency on low. Nothing to worry about, since it’s not going to be visible. Output is stable on mid and high.
Verdict
Vollsion MR12-D is a well built 18650 light. It is only available in cool white, and the smooth reflector causes some visible tint shift in the beam. While the hotspot looks clean cool white, the corona around is a bit greenish and spill cooler still. The output and throw measurements don’t match the manufacturer’s inflated specifications, but the differences aren’t too big. The performance is similar to other lights in the same category and you can improve the output by using a high current battery.
The output modes are a bit silly. There’s no real moonlight mode and the mid and high modes are visually too close to each other. I would have liked the mid to be somewhere around 250 lumens or at least to have another level between low and mid. The highest mode always steps down to mid level (~400 lm) after two minutes. The highest mode always steps down at two minutes regardless of temperature.
The user interface is easy to grasp and works perfectly. Click the tailcap to turn the light on, click the side switch to cycle modes. There’s no way to instantly access low from off, but that’s usually the case with these mechanical+electronic switch lights. Strobe is well hidden behind a long press of the side switch. The tailcap switch protrudes too much and the light cannot tailstand.
For the price, I’d rate it a fair performer, but most people I know would like to change the emitter to a bit warmer and higher CRI one, which isn’t too difficult to do on the MR12-D. There might have been some weak glue on the head, but it came off without any effort. There’s also lots of options for the 3535 LED footprint. The driver still needs improvement and considering the selling point of the light (USB input and output), it’s not easily done.
+Comes with a high quality battery which is rechargeable inside the light
+Very simple UI with no way to accidentally activate strobe
+High quality construction and nice switches
+Works as a power bank with decent efficiency
+The switching frequency on low is high enough to not be visible
-No neutral white or high CRI option
-Mid and high modes are too close to each other
-No real moonlight mode
-Large tint shift from hotspot to corona and spill when shone on a flat surface
-Cannot tailstand
-You’ll probably lose the OTG adapter at some point