Astrolux MF02 CW review w/ measurements (XHP35 HI, 4x18650)

Disclaimer: The Astrolux MF02 was provided for testing by free of charge

They are running a promotion on the MF02 til the 21th of December during which the price is $84.95 (non-tracking link)

The MF02 is the second light in the MF series of Astrolux’s multi battery monsters. The MF01 utilized 16 Nichia 219C or alternatively Cree XP-G3 emitters while the MF02 is a single XHP35 HI thrower with big promises. It offers an intense spot with an advertised throw of almost a mile (630000 candela, 1587 meters).

The only stock reflector LED flashlight with higher specs currently available is the Thrunite TN42 to which I’ll be comparing the MF02 in this review. This will of course change when the BLF GT is shipped to customers.

The MF02 is available in cool and neutral white. The light tested here is equipped with a cool white emitter.

Manufacturer’s specifications
Battery: 4x18650 (only button tops in stock configuration, not included)
LED: Cree XHP35 HI in cool or neutral white
Waterproof: IPX7
Impact resistance: 1.5 meters
Mode memory: yes, except special modes (strobe, sos, beacon)
Low voltage protection: side switch led indicator when battery voltage low, LVP cutoff at ~5.8V (2.9V per cell)
Thermal regulation: yes, 55°C
Mount: tripod, lanyard, shoulder strap connection points

Output specs
Maximum output: 3000 lumens (stepdown to 1800 lumens)
Other output levels: 1700/350/15 lumens
Light intensity: 630000 candela
Beam distance: 1587 meters
Special modes: strobe, sos, beacon

Measured dimensions and weight
Length: 189mm
Head width: 84.3mm
Handle width: 52.0mm
Tripod plate maximum width: 24mm
Weight: 816g plus 184g for the batteries

Box and contents
A very plain but sturdy white packaging with a shiny depiction of the MF02 on the top.

Bundled in the box with the light:
Shoulder strap
Two spare o-rings
Tripod adapter and a strap loop
User manual

There’s a good choice of retaining options. The wimpy lanyard may be useless, but there’s a holster as well as a shoulder strap included.

Physical appearance

There’s some heavy finning going on in the head of the light. The side switch is backlit. In standby it breathes slowly, but the light can be disabled by activating the electronic lockout mode. This is down by pressing the switch down for a couple of seconds in standby.

The tripod thread has the larger threads for mic stands and with the included adapter the light can be mounted on a standard camera tripod. Included in the package is a loop connector for attaching the shoulder strap.

The light disassembles to four parts. The tailcap and body tube don’t conduct any current and are just used to hold the carrier in place. The threads are triangular and quite thin. The anodizing was already wearing out the other end, but since they are not part of the electronic circuit, this doesn’t cause any problems with physical lockout. There was no lubricant in the threads or o-rings on my sample.

Batteries are inserted in a separate carrier (2S2P). The center contact is positive and connects to the spring on the driver. The outer edge connects to the brass retaining ring.
You can remove the plastic spacers if you want to use flat tops, but as there is reportedly no polarity protection in the driver care should be taken with the orientation. Short flat tops such as Samsung 30Qs may also be quite loose in the carrier.

The brass retaining ring is attached with three torx screws. The screws were very loose. For some reason, there was thermal paste between that and the driver. The paste was also covering the contacs which will interfere with the current flow.

The boost driver converts <8.4 volts to >12 volts for the XHP35 HI. It works well even with low input voltage and shuts off at about 5 volts input (or 2.5 volts per battery).

Removing the bezel and the glass lens required the use of some straps. There was no visible glue though.

The MCBPCB used has a diameter of 28mm and is held down with two phillips screws. The wires are AWG 22. I already noticed some dark spots on the emitter but can’t say whether they appeared only after my testing.

User interface

The light is operated via an electronic side switch. It has a backlight to help to find the light in the dark or to tell you that the batteries are running low.

Electronic and physical lockout are both possible. In electronic lockout the backlight will be off.

Operation is as follows
From off:
Single click turns the light on on previously used mode (strobe, sos and beacon are not memorized)
Double click turns the light on on turbo
Triple (or more) click turns the light on on strobe
Press and hold to activate lockcout (switch light turns off), repeat to unlock

From on:
Single click to cycle modes (low, mid, high, turbo, low…)
Long press to turn the light off
Double click activates turbo
Triple click for special mode group, single click to advance through them (strobe, sos, beacon, strobe…)

Only thing I would critizise is that you can’t directly access the lowest mode from off if the previous mode was something else. For some the long click to off might be a turnoff. The double click for turbo or triple to strobe have to be quick enough so accidental activation when cycling throug normal modes should not be an issue.

Size and beamshot comparison

The Thrunite TN42 is the only comparable thrower I have, but I’ve included some of the smaller throwers here as well even though they’re not in the same league as the big ones.

Astrolux MF02 (4x18650), Thrunite TN42 (4x18650), Utorch UT02 (26650), Emisar D1S (18650)

Astrolux MF02 (4x18650), Thrunite TN42 (4x18650), Emisar D1S (18650), Utorch UT02 (26650)

Astrolux MF02, Thrunite TN42

Individual beamshots
Astrolux MF02
Thrunite TN42
Emisar D1S
Utorch UT02

Individual beamshots
Astrolux MF02
Thrunite TN42
Emisar D1S
Utorch UT02

Individual beamshots
Astrolux MF02
Thrunite TN42
Emisar D1S
Utorch UT02

Beam and tint

Overall the beam is very pleasing, which is not surprising considering the emitter used.

The color temperature is heavily affected by the output mode. On higher modes the light is much cooler but also more neutral (closer to the BBL). On high the tint is pleasantly neutral cool white at 6150K and duv of 0.0015. For best visibility on far away subjects you should still choose the neutral white version.

Tint in different modes:

TN42 tint in different modes for comparison:

Tint within the beam:

Even though the tint shift within the beam is large in the graph, it’s not very visible in real life. That’s because the relative brightness of the corona and spill is very low. The output has dropped to 1/100 on the corona. In the graph you can see that the 10% output point is actually quite close to the hotspot in terms of tint.

The actual hotspot is pretty much identical in size to the Thrunite TN42, but the focus is worse so the edges blend more gradually to the spill. This makes the spot look a bit larger with large distances but results in less throw.

The lens has a mild AR coating. It has a transmissitivity of 97.9% with a tint deviation of deltaxy 0.0021. It has a slight but not noticeable green shift but no effect on CRI.

Spectral data and 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.

Explanation of abbreviations

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 green.

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.

CRI data on turbo

CRI data on mid

Output and runtimes

All tests were done with a set of unprotected button top Samsung 30Qs. Using higher discharge cells such as the Sony VTC5As only results in about one percent of initial output increase.

The actual output falls short of the advertised values, which wasn’t too unexpected. Tests have shown that the XHP35 HI doesn’t really offer much more output after 2 amps. The specified 3000 lumens is totally unrealistic.

2200 lumens with the reflector and lens losses is still running the emitter close to its limits. Using a smaller reflector than on the TN42, there was no way it would reach the specified 630kcd when the TN42 is doing 600kcd at 2000 lumens.

That isn’t to say that the MF02 is disappointing. It does take good advantage of the XHP35 HI and for the reflector size the throw is great at 420kcd. The focus isn’t perfect and with tuning there might be some more candelas to achieve.

The difference in real life to the 620kcd I measured from my TN42 is still noticeable, but the TN42 is also a bigger light. The neutral white emitter in the TN42 also has an advantage with seeing far away objects more clearly.

I have graphed the runtimes with lumens and candelas for the higher modes, since with throwers the latter is usually what matters.

Standby drain

There’s significant parasitic drain on the battery when the light is switched off. This is mostly due to the lighted switch, but the drain is not insignificant in lockout mode as well, where the backlight is off.

Normal standby: 3mA
Electronic lockout: 0.57mA

It will take about 80 days to drain four 3000mAh batteries in normal standby mode. In electronic lockout mode this time increases to 440 days or 14 months. To prevent this it is recommended to break the electronic circuit by twisting the tailcap open half a turn.


I measure the flicker with a Thorlabs DET36A/M photodetector and an oscilloscope. I transfer the scope’s sample memory via LAN to the computer where a script parses, performs an fft and other calculations to spit out a bunch of metrics. Then another script draws a graph which represents the output of the light source relative to time. This graph also has the metrics calculated previously.

Here are the metrics:

Frequency – the rate of flicker in hertz. If this is over 10kHz, there’s usually no reason to worry about visible flickering
Modulation – also known as percent flicker which is calculated by (max level – min level) / (max level + min level). 100% modulation means that the light is turning completely off during the cycles like on PWM controlled output
Duty cycle: the relative time the light spends above the mid level during one cycle. 50% means that the light is above mid (“on”) 50% and below mid (“off”) 50% of the time. Lower duty cycle results in more visible flickering or strobe effect
Index: flicker index is calculated using the area under the curve (link is external). This integral is separated into area above and below the average output. The index is the area above that average divided by the total area. A pwm light with a duty cycle of 50% will have a flicker index of 0.5, but it is more useful with more complicated periodic waveforms, especially those whose modulation is less than 100%.

Snob index: a rating, which tries to convey a single number of flicker visibility
0% - No flicker, completely stable output
<1% - Could be considered flicker free unless photographed with a super high shutter speed with the camera stuck on the LED
1-5% - Probably not visible to the naked eye (high frequency PWM, >10kHz or low modulation at lower frequencies)
5-10% - Might be visible to the most sensitive people who know what to look for and try hard enough (incandescent)
10-20% - Sensitive people will see it at least on bright reflections, probably not a dealbreaker yet in general use
20-50% - YMMV area. If you can usually spot mid frequency PWM, you’ll easily see the flicker
>50% - Visible to most people at least on some occasions (low frequency PWM, <200 Hz)

There’s no visible flicker on any of the modes. I couldn’t see anything with a cellphone camera either.

The high mode is completely stable in output, but there’s high frequency but low modulation ripple on the other modes. None of them is visible and I couldn’t see anything with a cellphone camera either.


Thanks to an active temperature control the light heats up to about 50°C on turbo and steps down in room temperature without cooling. The highest surface temperature I measured was 53°C at a couple of minutes after the stepdown. On the lower modes the light doesn’t get very hot (46°C on high).

As the light heats up on turbo (or cools down), there’s loud crackling noises from the bezel/lens.


Even though the Astrolux MF02 doesn’t reach advertised specs, it’s still one of the strongest reflector based LED throwers regardless of price. At below half the price ($84.95 at the time of writing this) of the current king, the Thrunite TN42, it’s a serious contender as it is significantly more compact and very well made.

The MF02 comes with very good arsenal of accessories to carry it with you. There’s a holster, a lanyard, shoulder strap and a tripod mount. The latter can only be used with small bases though, since the head tapers wider 12 mm from the screw hole.

It has good tint on the higher modes and the choice of cool and neutral white versions. I wouldn’t probably run the XHP35 HI quite as hot as the turbo does and would like one more output mode with a bit different spacing. This can be achieved with an aftermarket driver though.

The driver works well and boosts the output to turbo even with discharged batteries. The output is not regulated on mid however. The lighted switch LED does mean that the batteries will drain in a couple of months unless you lock out the light.

+ Impressive throw (even though not reaching spec)

  • Pleasing tint characteristics of the XHP35 HI especially on high (neutral white also available)
  • No visible flickering
  • Good boost driver enables the use of turbo with significantly discharged batteries
  • High mass sinks heat efficiently
  • Temperature regulation guarantees comfortable use
  • Very hefty and quality feel of the body
  • Low voltage protection

- Shouldn’t probably be driven quite so hard on turbo (large tint shift, possible decrease in lifetime)

- No direct access to the lowest mode from off

- Tripod mount area is too small for most plates

- High standby drain (empties a set of 18650s in 80 days)

- No lubrication on the threads from factory

- Liberal application of thermal paste on driver interferes with the current path

  • Mid mode is not regulated (haven’t tested low)

WOW… that was a very comprehensive report…
I will have to read it over later tonight.
Thank U maukka
Always a pleasure to read your reports/analysis…
Keep up the good work.
Merry Christmas

Thanks for very detailed review.

Luckily I request a refund.
Smell something not right when they can’t fix a switch-off problem. Of course it’s just lucky hindsight.
Was hoping it is driving XHP35 real hard to get let’s say 2500lumens, then candela get to 600kcd range.
420kcd is very respectable performance for its price but it’s too far from spec, some might think it is scam.

thanks for a great review.

Thank you for the clearly extensive work that you put into what I think will continue to be the definitive review of this light, if not a benchmark for other reviews to come. It gives prospective buyers a transparent view of what to expect. Thank you.

Great review. I am looking forward to getting mine. Thanks for your efforts.

Excellent review, thank you :slight_smile:

Perfect, someday should I test the nw model?

Wow! Extraordinary review(s), maukka! Many thanks for this.
I’m still waiting mine MF02 CW. DHL is expecting it so in a next few days I could try it I guess. :slight_smile:
If it’s not hard to answer…. What is the best solution to do about thermal paste on driver? Just wipe it off and tighten three torx screws?
Best regards

I just wiped it off with a tissue and cleaned the smudges with isopropyl alcohol.

I actually added a super small dab of paste on the backside of the driver between he the screw holes (where the little holes are) just in case there was some real thought behind it in the first place to keep it cooler. Doubtful though since there’s no real metal thermal path that would facilitate such a thing.

Perfect! Will do the same after first tests. Thanks!

Thanks a lot for the review. Such a disappointment! We’ve seen 500 kcd measurement on MT35 and I expected this to do like 600 kcd.
And thermal stepdown!
I have to sleep it through whether not to cancel my order. It is not what I expected it to be, but it is still the best throw for the price. And there’s nothing better on the horizon.

A bit ambitious numbers :smiley: I measured 370kcd on the Mt35 i tested …

I haven’s seen different numbers yet….

Great review, thank you.

Nice review. Got to decide if I cancel the NW I have on order.

Thanks for the review maukka. Agree that it’s great value for the memory even though it doesn’t hit the specs

Very great detailed review. Thanks a lot!

Thanks Maukka for this brilliant review. This review is really impressive. I’m so glad I cancelled my two mf02 orders with Banggood. The throwing distance is disappointed after they stated 1587 meter distance. Not even to mention the lumens output specs from Astrolux. The actual output falls short of the advertised values, which wasn’t too unexpected. My first choice of course my Thrunite TN42 CW.

Maukka, we’re you able to do any amp draw tests? One owner said his light was drawing about 6A which I assumed would be more than 2A at the emitter. I was thinking 2.5A (80% driver efficiency) or 2.7A (90% driver efficiency). Maybe being a boost driver it’s not so simple to calculate loads at the emitter?

I can see the MF02 has a different driver than the MT35, but they still seem to put out the same 2000 to 2100 lumen. Any idea why?