Astrolux S41 measurements (Quad Nichia 219B, 18350/16340/18650)

EDIT 2016/3/6: verified the pwm frequency, which is 17.2 kHz on all modes except moonlight (8.6 kHz) and turbo (no pwm).




Astrolux S41 is a quad emitter hotrod light manufactured by Manker. It is equipped with either high CRI Nichia 219b or cool white Cree XP-G2 LEDs. My light is the Nichia variant purchased from banggood. The light is also available as a Manker E14.

Manufacturer specifications

* Battery type: 1x 18350, 16340 or 18650 with an optional tube
* LED: 4x Nichia 219B 5000 K (also available with 4x CREE XP-G2 6500 K)
* Body material: Aluminum/Copper
* Switch type: Reverse tailcap clicky
* Waterproof: Yes, IPX8
* Lens: TIR
* Protection: Low voltage warning (2.9-3.1 V), reverse polarity
* Modes: Selectable 4 or 7
* Special modes: 10 Hz strobe, battery check, biking flasher
* Mode memory: Selectable
* Length: 80 mm
* Width: 24 mm
* Weight: 90 g

The S41 driver is the same as in the popular BLF A6/Astrolux S1.




Astrolux S41 with a 18650 and a 18350 battery.


The light accepts protected and unprotected cells. In addition to 18350s 18650s can be used with an option 18650 tube. There's a double spring in the tailcap.


Measurements
Please note: lumen measurements are only rough estimates
My diy 30 cm integrating styrofoam sphere has been calibrated using a Fenix E05 on high with manufacturer's claim of 85 lumens. Verified with an Olight S10 that has been measured with a Labsphere FS2 integrating sphere by valostore.fi. Results may be more inaccurate with especially throwy or floody lights.

For spectral information and CRI calculations I have an X-rite i1Pro spectrophotometer with HCFR for the plot and ArgyllCMS spotread.exe for the data. For runtime tests I use spotread.exe with a custom script and a 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
x,y = coordinates on a CIE 1931 chart





After 35 seconds on turbo with a 18650 battery, my lights drops down to moonlight and doesn't recover before switching it back off and on again. The backward mode cycling with a long press also stops working after overheating.



Spectral distribution


Color rendering







Beam and tint


Tint in different brightness modes is consistent. Mode 1 = moonlight, Mode 7 = Turbo.

Runtime

High 2 and Turbo



Medium 2 and High 1

Thanks for another interesting set of measurements.

Very interesting, thank you!

The one time I let my Manker version hit the turbo stepdown with a NCR18650GA, it seemed to work properly... The head was very hot though. I wonder if some units handle the heat a little better or the NCR18650GA was giving me a little less output with the 10a rated max. Will try again tonight and see what happens.

Awesome work, thanks for taking the time

With 1175 lumens, its not putting out anymore than a single XML or XPL LED. Some reviews on bangood claim 2000 lumens but who knows how accurate those claims are...

carl said:

With 1175 lumens, its not putting out anymore than a single XML or XPL LED. Some reviews on bangood claim 2000 lumens but who knows how accurate those claims are...

Click to expand...

I think this light uses a FET+1 driver with 4x Nichia 219B. Those old 219Bs have great tint and 90+ CRI, but they don't actually put out a lot of light.

That said, this light looks like it should be very easy to "hot-rod", as it does have a direct-copper star and accepts a 17mm driver. Replacing the emitters with 4x XPL HI or XPG3 should easily get you over 2000 and maybe even 3000 lumens for a brief period of time. I suggest also replacing the driver with one with a temp sensor in it such as Bistro or H17F. The pill-less copper heatsink might get burning hot in seconds if you run it all out with those emitters.

Thank you for great review.
:twothumbs

carl said:

With 1175 lumens, its not putting out anymore than a single XML or XPL LED. Some reviews on bangood claim 2000 lumens but who knows how accurate those claims are...

Click to expand...

Considering the Nichia's is rated for 300lumens each, take those claims with a pinch, or make it a jar of salt

p/s: Excellence review @maukka

akhyar said:

Considering the Nichia's is rated for 300lumens each, take those claims with a pinch, or make it a jar of salt

p/s: Excellence review @maukka

Click to expand...

Nichias are rated 300 lumens each when run at spec. A FET driver combined with a quality IMR 18350 or 18650 might provide enough current to drive them beyond spec. Actual output could be higher. However, this light isn't going to hit 2K lumens without upgrading the emitters to something more modern.

Great Review !!

Thank you very much, lots of interesting information. Have one on order.

Fireclaw18 said:

Nichias are rated 300 lumens each when run at spec. A FET driver combined with a quality IMR 18350 or 18650 might provide enough current to drive them beyond spec. Actual output could be higher. However, this light isn't going to hit 2K lumens without upgrading the emitters to something more modern.

Click to expand...

Agree with what you're saying.
Just that to hit 2k lumens as what is claims at BG forum, each emitter is running about 500 lumens, which could be way pass it's treshhold.

Pity why Mankers/Banggood use the BLF S6 driver, when the Bistro X5/X6 driver are available for most probably additional 2-3 bucks.

Anyway, back to this light.
My Astrolux S41 has slightly yellowish tint compared to my Sinner Triple, which also uses Nichia 219B at 4700K.
On white wall, the beam on my Sinner is a bit rose tinted.
The colour is closer to my ReyLight Triple running on Nichia 219C at 5K.

But whatever it is, still a great light considering the $32 I paid for being an early bird.

Thanks for the review, maukka, wonderfully informative as always!

I noticed that the initial 1315lm on Turbo isn't far off the Manker / Banggood rating of 1400lm, and neither company claims to test according to the ANSI FL1 standard, as far as I know. It wouldn't surprise me if they were using the initial output at switch-on for their ratings.

If that were the case, I could easily see the difference being down to sample variation between lights and / or Manker / Banggood cherry-picking their test samples.

I'll be keeping those thoughts in mind when evaluating the specifications for their future lights.

Now back to waiting until I can try out an S41 of my own

Edit: My S41 has arrived, with many good points and a couple of bad ones. I've posted my thoughts in the manufacturer thread.

maukka said:

EDIT 2016/3/6: verified the pwm frequency, which is 17.2 kHz on all modes except moonlight (8.6 kHz) and turbo (no pwm).

Click to expand...

It's 17.2 kHz PWM with "full" duty cycle (down to zero) ?
May be, you have measurements of this PWM ?

Thanks, I found answer in another your review,
"See all the scope screenshots here: http://imgur.com/a/xsere"
It's PWM with high freq. and very low flicker %.

I got my S41 Cree XP-G2 version the other day. Here's some lumen measurements compared to the Nichia one. CRI was around 70, but I'll post more data later.

Wow!
That is pretty high lumens @ 30 seconds on 30Q

I'm new to Nichia leds but my S41 with Samsung 30Q Amperage peaks at 13A and 14A with the Sony VTC4. I have a feeling the lumen output is much higher than what you're claiming.

Aleredy had the manker e14 with 18650 and 18350 tube. So i bought a astrolux s41 switch and head for the extra tube. Noticed some differences. The astrolux had better tint, but the beam quality was better on the manker. Manker had a big round hotspot and the astrolux had smaller hotspot with a funky corona. Same optic with same led should give same beam, so i had to do something with it. Grinded down the plastic feet for the optics and a little on the sides of the feet to mount the optic closer to the leds. Now the beam is as it should be, but since the optic is mounted deeper, i had to install a thicker o-ring for the glass lense to make it 100% waterproof.